1. business and industrial
2. chemicals industry
3. plastics and polymers

The Indian Roads Congress
E-mail: [email protected]/[email protected]
Volume 42
Founded : December 1934
IRC Website: www.irc.org.in
Number 11
Contents
November 2014
ISSN 0376-7256
Page
2
From the Editor’s Desk - “Does Acts and Verdict(s) framed for public good reach the common man urposefully?
Enhancing Public Awareness”
3
Important Announcement Regarding International Conference of IRC
Page
4
Technical Papers
Performance Characteristics of Bituminous Mixes Modified by LDPE, HDPE and PP Granule
Sunil Kumar Pal &
by Vandana Tare
6
LRFD Approach for the Design of Reinforced Soil Walls: Comparative Study with the Convensional Methods
by
13
A.D. Maskar
&
S.S. Bhosale
Assessment of Suitability of Lime-Laterite Soils in the Construction of Road Base
T. Ghosh
by P.G. Bhattacharya
18
Kundan Meshram
&
R. Paul
Pedestrian Safety in Urban Situation
Er. V. Dinesh Kumar
23
Circular Issued by MoRT&H
24
Tender Notice, NH Tirunelveli
25
Tender Notice, NH Lucknow
& Er. S. Satheesh
Jamnagar House, Shahjahan Road,
New Delhi - 110 011
Tel : Secretary General: +91 (11) 2338 6486
Sectt. : (11) 2338 5395, 2338 7140, 2338 4543, 2338 6274
Fax : +91 (11) 2338 1649
Kama Koti Marg, Sector 6, R.K. Puram
New Delhi - 110 022
Tel : Secretary General : +91 (11) 2618 5303
Sectt. : (11) 2618 5273, 2617 1548, 2671 6778,
2618 5315, 2618 5319, Fax : +91 (11) 2618 3669
No part of this publication may be reproduced by any means without prior written permission from the Secretary General, IRC.
Edited and Published by Shri S.S. Nahar on behalf of the Indian Roads Congress (IRC), New Delhi. The responsibility of the contents and the
opinions expressed in Indian Highways is exclusively of the author/s concerned. IRC and the Editor disclaim responsibility and liability for any
statement or opinion, originality of contents and of any copyright violations by the authors. The opinions expressed in the papers and contents
published in the Indian Highways do not necessarily represent the views of the Editor or IRC.
From the Editor’s Desk
Does Acts and Verdict(s) framed for public good reach the
common man purposefully? Enhancing Public Awareness
Dear Readers,
on account of the fact that once life
is lost, the status quo ante cannot be
restored as resurrection is beyond the
capacity of man.
This has a reference to the landmark
Verdict dated 28.08.1989 of the
Hon’ble Supreme Court of India (DB)
in the matter of a writ petition in public • This decision shall be published in
interest filed by a human right activist
all journals reporting decisions of
Pt. Parmanand Katara on the basis of
this Court and adequate publicity
newspaper report concerning the death
highlighting these aspects should be
of a scooterist, who was knocked down
given by the national media as also
by a speeding car.
through the Doordarshan and the All
(website: http://judis.nic.in/supremecourt/
India Radio.
imgs1.aspx?filename=7839)
• The Code of Medical Ethics
2. The Hon’ble Supreme Court had
framed by the Medical Council was
inter alia observed:
approved on 23rd October, 1970.
This only reveals an unfortunate
• The Petitioner prayed for directions
state of affairs where the decisions
that every injured citizen brought
are taken at the higher level good
for medical treatment should
intentioned and for public good
instantaneously be given medical
but unfortunately do not reach the
aid to preserve life and thereafter the
common man and it only remains a
procedural criminal law should be
text good to read and attractive to
allowed to operate in order to avoid
quote.
negligent death. It is clear that there
is no legal impediment for a medical 3. Following the aforesaid Supreme
professional when he is called Court Verdict dated 28.08.1989,
upon or requested to attend to an
the Motor Vehicles Act (MVA) was
injured person needing his medical
amended in 1994, to make it mandatory
assistance immediately. There is also
on the part of both the driver/owner of
no doubt that the effort to save the
the vehicle to take the accident victim
person should be the top priority not
to the nearest doctor, and the doctor to
only of the medical professional but
treat the victim without waiting for any
even of the police or any other citizen
formalities. Section 134 of MVA states
who happens to be connected with
that driver and/or the person in-charge of
the matter or who happens to notice
the motor vehicle responsible for a road
such an incident or a situation.
accident is required to take all reasonable
•On behalf of Union of India, it was steps to secure medical attention for the
submitted that there are no provisions injured person by conveying him to the
in the Indian Penal Code, Criminal nearest medical practitioner or hospital,
Procedure Code, Motor Vehicles Act unless it is not practicable to do so on
etc. which prevents Doctors from account of mob fury or any other reason
promptly attending seriously injured beyond his control. Under Section 187 of
persons and accident case before the MVA, whoever fails to comply with the
arrival of Police and their taking into provisions of the clauses of Section 134,
cognizance of such cases, preparation shall be punishable with imprisonment
of F.I.R. and other formalities by the for a term which may extend to 3 months,
Police.
or with fine which may extend to Rs 500/• There can be no second opinion or with both. If it is the second time for
that preservation of human life is of the person concerned, then the penalty is
paramount importance. That is so harsher. The imprisonment may extend
Place : New Delhi
Dated : 21st October, 2014
2
to 6 months, or with
fine which may extend
to Rs.1,000/- or with
both.
4. The basic question,
whether the aforesaid
Verdict/Government directives framed
for helping accident victims could reach
the common man actually remained
unanswered. I experienced a jerk
when a social periodic program named
‘Mumkin Hai’ anchored by one of the
illustrious film stars was telecast on a TV
channel, where the help to road accident
victim was being discussed in detail.
Possibly many of us may have viewed
the program. It was disheartening to
see that there was hardly anyone in the
live telecast who was aware about the
exemption from the legal formalities to
the person providing such a help to the
road accident victim pronounced by the
highest Court of our land over 25 years
ago.
5. The vital issue arises as to how to
improve the implementation mechanism
and what is the way forward to enhance
public awareness.
6. In order to take into cognizance the
challenges being faced in enhancing
road safety and to pool our collective
wisdom, the IRC in collaboration with
the World Road Association; the World
Bank; Japan International Cooperation
Agency (JICA); International Road
Federation and ADB is organizing an
International Conference on “Road
Safety Scenario in India and Way
Forward” at Vigyan Bhavan, New
Delhi on 29-30 November, 2014
(Saturday & Sunday).
7. I would like to appeal to all our
fraternity to join in this endeavour and
to share their experience and wisdom in
this noble cause of saving avoidable loss
of lives and injury due to road accidents
and identify an implementable and
sustainable Road Safety Action Plan.
(S.S. Nahar)
Secretary General
E-mail: [email protected]
INDIAN HIGHWAYS, November 2014
Important ANNOUNCEMENT
ReScheduling of International Conference
International Conference on “Road Safety Scenario in India and Way Forward”
will now be held on 29 and 30 November, 2014 (Saturday and Sunday)
at Vigyan Bhawan, New Delhi
Organizers :
Indian Roads Congress (IRC),
Organizing Partners : World Road Association (Piarc)
Japan International Co-operation Agency (JICA)
International Road Federation
The World Bank (Global Road Safety Facility) and
Asian Development Bank (ADB)
Who should attend : Govt./PSU/Autonomous Organization/NGO's/Emergency Medical Service
Providers/Insurance Companies/Automobile Manufacturers/Traffic Police/Law Enforcing Agency/
Research & Academic Institutions/Transporter/Cargo Movers/Fleet Operators/Device Manufacturers,
including all Individuals/Corporators directly or indirectly associated with the Cause of Road Safety.
Tentative Themes of the Conference :
Session 1:Overview of Traffic Rules & Regulations: Best Practices in the World (UK, Japan)
Session 2:
Road Safety Audit: Best Practices in the World
Session 3:Overview of Urban & Non-Urban Traffic: Sustainable Way of Traffic Management
including Medical Aid
Session 4:Overview of Road Users’ Behaviour: Innovative Methods for Mass Awareness
Movement
Session 5:
Review of Design of Vehicles : Innovative & Environmental Friendly Techniques
Session 6:
Panel Discussion & Suggested Way Forward – Short/Long Term.
Focal Point: Shri Rahul V. Patil, Deputy Director (Technical), IRC (E-mail: [email protected] &
[email protected]) Tel. 011 – 2671 6778.
● Opportunity available for Advertisers
● Opportunity available for Sponsorship
● Opportunity available for Registration (by Invitation only)
For further details and enquiry for getting associated with the International Conference, please
contact on E-mail: [email protected], Tel. No.: 2617 1548 and E-mail: [email protected],
Tel. No.: 2338 7140.
INDIAN HIGHWAYS, November 2014
3
Performance Characteristics of Bituminous Mixes
Modified by LDPE, HDPE and PP Granule
Vandana Tare*, Sunil Kumar Pal** and Kundan Meshram***
ABSTRACT
Use of plastic waste in the construction of flexible pavement is gaining importance because of the several reasons. Utilize this type
of non- biodegradable material in bituminous mixes substantially improving the stability or strength, fatigue life and other desirable
properties, even under adverse water-logging conditions. Therefore, the life of the pavement surfacing course using the modified
bitumen is also expected to increase substantially in comparison to the use of ordinary bitumen. Bitumen mixes do not perform up to
the expectations for following reasons:
1.
Bitumen does not have an affinity with water, which leads to pothole formation during and after rains.
2.
With high air void ratio, top-down cracking is initiated, which makes the mix less durable.
The present work has attempted to find solutions to these weaknesses of bitumen mix (DBM) by partial substitution/replacement of
bitumen by granules of Low Density Polyethylene (LDPE), High Density Polyethylene (HDPE) and Poly-Propylene (PP).
1 INTRODUCTION
The bituminous mixes have been
performing as the standard material
for road construction not only in India,
but across the world. The performance
of the pavement has scope for further
improvement in various aspects.
However, existing highway systems
have been dealing with increased traffic
volume, higher axle load and tyre
pressure and extreme environmental
impacts.
It has been possible to improve the
performance of bituminous mixes
used in the surfacing course of
pavements, with the help of various
types of additives to bitumen such as
polymers, rubber latex, crumb rubbertreated with some chemicals etc.
Re-cycled plastic waste viz. LDPE,
HDPE and PP may be useful in
bituminous pavements, resulting in
reduced permanent deformation in
the form of rutting and reduced lowtemperature cracking of the pavement
surfacing. It gives also greater
durability and fatigue life has been
reported in these modified mixes.
varying percentage (6% to 14%) of
plastic granules.
2. To compare the various properties
of bitumen with and without
additives.
3. Find out optimum percentages of
plastic granules.
2OBJECTIVES OF THE STUDY
This study has been done for following
objectives:
1. To study the characteristics of
Bituminous mix (DBM) with
3 EXPERIMENTAL PROGRAMME
3.1Materials
Properties of aggregate are shown in
Table 1.
Table 1 Properties of Aggregate
Impact Value
(%)
17.27
Specific Gravity
C.A – 2.82
F.A – 2.73
Filler -3.08
Properties of bitumen with and without
Water Absorption
(%)
1.57
Shape Test
(%)
20.82
additives are given in Table 2.
Table 2 Physical Properties of Conventional Bitumen and Modified Bitumen
S. N.
1
2
3
4
Particular
Bitumen without additives
Bitumen with LDPE
Bitumen with HDPE
Bitumen with PP
4TEST RESULTS
Bituminous mix samples were
prepared with varying % of LDPE,
HDPE and PP. These samples
subjected to Marshall Test in
the
laboratory.
Marshall
Test
results for bitumen are shown in
Table 3.
Penetration (mm)
67 at 25ºC
63 at 39ºC
30 at 45ºC
62 at 38ºC
Ductility (cm)
91
85
60
34.4
The interpretation of the curves (shown
in Figs. 1 to 6) is as follows:
1 Flow value
1. Flow value for LDPE lies in the
standard range of MoRT&H from
2 to 4. The flow value is found to
be minimum for 10 % additive.
Softening Point (ºC) Specific Gravity
51ºC
1
65ºC
0.988
60ºC
0.993
65ºC
0.994
2. Flow value for HDPE comes out to
be 4.85 to 3.47 which are slightly
towards the higher side of the
standard range of MoRT&H.
3. Flow value for PP comes ut to be
3.81 to 3.36 with additive at 10% to
14% which are within the standard
range of MoRT&H from 2 to 4%.
* Professor, SGSITS, Indore. ** Assistant Engineer, MPAKVN, Indore. *** Research Scholar, MANIT Bhopal
E-mail: [email protected]
4
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
Table 3 Marshall Test Results for 60/70 Grade of Bitumen
S.N.
Properties
1
2
3
4
OBC (%)
Bulk Density (gm/cc)
Air voids (%)
Voids in mineral Aggregates
(VMA in %)
Voids filled with Bitumen (VFB
in %)
Stability (kN)
Flow value (mm)
5
6
7
60/70 Grade of
Bitumen
4.8
2.435
4.5
14.4
MoRT&H
Specifications
4.5 minimum
3 to 5
13 to 15
74.8
65 to 75
12.35
3.4
9.0 minimum
2 to 4
Fig. 1 Granular % V/S Flow
Fig. 5 Granular % V/S VMA
PP, are within limits and is minimum
for 6% additive.
3. A sinusoidal curve is obtained in
case of HDPE and PP as additive and
the value of Vv is found to be in the
standard range of MoRT&H.
4 Voids in Mineral Aggregates (VMA)
1. The VMA is maximum in case of LDPE,
while in HDPE and PP additives, we
find almost same values of VMA with
sinusoidal curves.
2. For LDPE, HDPE and PP additives, the
value of VMA is found to be 15% to
19% which is higher than the standard
value of 12.5% specified in MoRT&H.
5 Voids Filled with Bitumen (VFB)
1.VFB increases when the % of LDPE
as additive increases from 6% to 10%,
afterwards, with increase in additive,
VFB decreases.
2. In case of HDPE and PP, sinusoidal
curve is obtained and the values of
VFB obtained, lie between the standard
value specified in MoRT&H.
5 CONCLUSIONS
Fig. 2 Granular % V/S Stability
Fig. 6 Granular % V/S VFB
2Marshall’s Stability
1. Stability increases with increase in %
of additives i.e. LDPE, HDPE and PP. The
standard value specified in MoRT&H is
9.0 kN or 900 kg.
Fig. 3 Granular % V/S Vv
2. The increase in stability is more up to
10% of additives, after which the growth
rate becomes lower.
3. Maximum stability, observed with LDPE,
HDPE and PP as additive, is 1626.67 kg,
1833.33 kg and 1900 kg respectively which
is higher than MoRT&H’s specification.
3
Fig. 4 Granular % V/S Vb
Percentage
of
Volume
of
Voids (Vv)
1. % Air voids obtained for LDPE are
within limits and minimum for 10%
additive.
2. % Air voids obtained for HDPE and
INDIAN HIGHWAYS, November 2014
Based on the study following conclusions
have been drawn:
1. With the replacement of 60/70 grade
bitumen by granules of LDPE, HDPE
and PP, the characteristics of bitumen
mix in DBM are improved.
2. Stability increase with increase in
percentage of additives i.e. LDPE,
HDPE and PP.
3. Flow value for the mixes with PP,
HDPE, and LDPE comes out to be
within the standard range of MoRT&H
from 2 to 4.
4. The % air void are within permissible
limits set by MoRT&H, with the use
of 10% LDPE, 6% HDPE and 6% PP
granules in the mixes.
5. For LDPE, HDPE and PP additives,
the value of voids in mineral aggregate
(VMA) is found to be 15% to 19%
which is higher than the standard
value of 12.5% specified in MoRT&H,
which may be due to the properties
of additives and the additives are not
properly absorbed in aggregates.
6. The optimum percentage of additives,
in case of LPDE, HPDE and PP are
recommended to be 10.70%, 8.7% and
8.7% respectively.
5
“LRFD APPROACH FOR THE DESIGN OF REINFORCED SOIL WALLS: COMPARATIVE
STUDY WITH THE CONVENSIONAL METHODS”
A.D. Maskar* and S.S. Bhosale**
ABSTRACT
In this paper, the detail of Load and Resistance Factor Design (LRFD) approach which is based on reliability concept for the design
of Reinforced Soil (RS) walls is presented. For conventional methods i.e Allowable Stress Design (ASD) Method, the factor of safety
is applied only for the resistance and loads are considered without variations. In LRFD method, the factor of safety is applied for both
load and resistance. Due to availability of large statistical data and economy, this method is preferred for the design of the RS walls.
An attempt is made to solve a numerical example of geosynthetic RS walls due to soil self-weight plus permanent uniform surcharge.
The example is solved using LRFD as well as other conventional methods (ASD) viz. FHWA, Modified Rankine, NCMA and B.S
Code Methods and the results of the LRFD methods are compared with conventional design methods and concluding remarks are
presented. The various equations have been obtained based on various curves plotted by using ASD and LRFD approaches. These
equations reveal if FOS against tensile rupture is known for any RS wall having 7m height and same properties and environmental
conditions as mentioned in current study then FOS against pullout failure and pullout capacity can be computed for these walls
without performing actual pullout test.
1 INTRODUCTION
1.1Preamble
In traditionally, the Reinforced
Soil (RS) walls are designed using
Allowable Stress Design (ASD)
approach.
As RS wall being geotechnical
structure, a lot of uncertainties
have been involved in geotechnical
parameters and hence there is ample
scope of an economical design of the
RS wall. Presently there are guidelines
for Load and Resistance Factor Design
(LRFD) approach which is more
economical than the ASD approaches
due to proper FS. RS walls can be
designed for both external and internal
stability considerations;
a) External stability consideration:
Sliding,
Bearing
capacity,
overturning about the toe of the
wall etc.
b) Internal stability consideration:
Tensile
overstress,
Pullout
Resistance, Facing connection
overstress etc.
1.2Conventional Methods/Allowable
Stress Design (ASD) Methods
There are various conventional
methods through which the RS walls
can be analysed (Koerner, 2001)
a) A Modified Rankine approach.
b) The
Federal
Highway
Administration approach (FHWA)
c) The National Concrete Masonry
Association approach (NCMA)
d) BS Code Method BS 8006:1995.
Fundamental equation governing ASD
approach is given by,
... (1)
Rn/FS ≥ ΣQi
Where,
Rn =
Nominal Resistance, ΣQi
= Sum of all Loads, FS = Factor of
Safety.
Graphically, the ASD approach
can be illustrated as shown in
Fig. 1 which isone of the principal
limitation of ASD approach, wherein
the values of Q and Rn are assumed
to be unique so that they have a
probability of occurrence as unity.
Fig. 1 ASD Design Approach
(FHWA 2001)
1.3Limitations of ASD Approach
 Does not adequately account for the
variability of loads and resistances.
The FS is applied only to resistance
and loads are considered without
variation.
 Does not represent a reasonable
measure of strength which is more
fundamental measures of resistance
than the allowable stress.
 Selection of the FS is subjective
and does not provide a measure of
reality in terms of probability of
failure.
2Load and Resistance
Factor Design (LRFD)
Approach
In LRFD approach, the resistance side
is multiplied by a statistically-based
resistance factor φ whose value is
usually less than one which accounts
for the various factors like weaker
foundation soils than expected, poor
construction of the RS wall sand its
materials such as earth, geogrids or
steel strips that may not completely
satisfy the requirements in the
specifications.
The load components on the right
side are multiplied by their respective
statistically based load factors, γi,
whose values are usually greater
than one. Because the load effect
at a particular limit state involves a
combination of different load types,
the load factors differ in magnitude
for the various load types. Therefore,
the load effects can be represented by
a summation of γi Qi products. If the
* Amol D. Maskar, Research Scholar, E-mail: [email protected]. ** Sukhanand S. Bhosale, Professor, E-mail: [email protected]
(Department of Civil Engineering, College of Engineering, Pune)
6
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
nominal resistance is given by Rn, then
the safety criterion can be written as,
Rr = φ Rn ≥ Σηiγi Qi
... (2)
Where,
φ = Statistically-based resistance
factor (dimensionless), Rn = Nominal
resistance, ηi = Load modifier to
account for effects of ductility,
redundancy and operational importance
(dimensionless), γi = Statisticallybased load factor (dimensionless),
Qi = Load effect.
Because of the above equation involves
both load and resistance factors, the
design method is called Load and
Resistance Factor Design (LRFD)
method. For a satisfactory design, the
factored nominal resistance should
equal or exceed the sum of the factored
load effects for a particular limit state.
Load and resistance factors are chosen
so that in the highly improbable event
that the nominal resistance of the RS
wall elements is overestimated and
at the same time the loads are under
estimated. There is a reasonably high
probability that the actual resistance
of the RS wall elements should still be
large to support the loads. Fig. 2 implies
that safety margin for ASD approach is
more as compared to that of the LRFD
approach due to unfactored loads and
resistance in ASD approach. Therefore,
LRFD approach is more economical as
compared to ASD approach.
Fig. 2 Combination of ASD and
LRFD Approach
2.1Problem Formulation
Bathurstet. al. (2008) developed both
load and resistance models for the
design of the RS walls. Those load &
resistance factors can be estimated by
collecting data from laboratory and
field pullout tests for RS wall having
steel strips as a reinforcing material.
Thus, from the another literatures, it is
found that no attempt has been made
for LRFD calibration of RS wall using
geogrid as a reinforcement and soil
self weight plus permanent uniform
surcharge as a loading condition.
Hence, it is necessary to design
RS walls using LRFD approach
and compared the same with ASD
approaches.
2.2Aim and Objectives
Review of Load and Resistance Factors
Design (LRFD) approach for the design
of RS walls and its results are compared
with conventional design methods
(ASD methods) viz. FHWA, Modified
Rankine, NCMA and B.S Code
Methods and certain conclusions are
drawn.
3LRFD
Calibration
of
Pullout Limit Test
The LRFD calibration of RS wall using
geogrid as a reinforcement and soil
self weight plus permanent uniform
surcharge as a loading condition is
used in the current study. Its limit state
function for pullout failure is given
by,
φPC – γQTmax ≥ 0
... (3)
Where,
Pc = Nominal calculated pullout
capacity (Rn), Tmax = Nominal
calculated maximum reinforcement
load (Qn), φ = corresponding resistance
factor, γQ = corresponding load factor
applicable to internal stability of RS
wall.
3.1AASHTO Modified Simplified
Method for Load Models
The maximum reinforcement load
(Tmax) using AASHTO Simplified
Method is computed as (For Self wt +
uniform surcharge),
Tmax = λ Sv Kr σ v + λ Sv Kr q gives,
Tmax = λ Sv Krγb (Z + S)
... (4)
Where,
λ = Bias factor (for current AASHTO
INDIAN HIGHWAYS, November 2014
= 1, for Modified AASHTO = 0.30
& 0.15), Sv = Vertical spacing of the
reinforcement layer, Kr = Lateral
earth pressure coefficient (1.7 Ka
to 1.2 Ka for Steel strips and Ka for
geosynthetic), σ v = Normal stress
due to self-weight of the backfill
(γb Z) and equivalent height of
uniform surcharge pressure (S = q/ γb),
γb = Bulk unit weight of soil, z = Depth
below crest of the wall, q = Uniform
distributed surcharge.
Reinforcement Load Data and Bias
Statistics
The reinforcement load data for 7 m
high RS walls containing surcharge
load (q) varying from 10 kPa to
30 kPa and angle of internal friction
(φ) for backfill varying from 28º to
36º, is available from different case
studies reported by Allen et al. (2002),
Miyata and Bathurst (2007a,b) and
Bathurst et al. (2008b). This data is
used to compute maximum tensile load
Tmax (Calculated load) in the geogrid
at each layer using Eq (4). By knowing
measured load (Q), the load bias can
be computed at each layer of geogrids
using equation given by Bathurst et al
(2008).
The constant coefficient λis called
bias factor which introduced in Eq(4).
When λ = 1, the current AASHTO
Simplified Method is used to compute
maximum tensile load in each geogrid
layer for φ backfill whereas, when λ =
0.3 and 0.15,the Modified AASHTO
Simplified Method is used to compute
maximum tensile load in each geogrid
layer for φ and C-φ backfill soil cases,
respectively.
3.1.1 Current AASHTO Simplified
Method (λ = 1)
Fig. 3 shows measured versus
calculated (Tmax) load values using the
current AASHTO Simplified Method
for all wall cases in the database used
in this study with cohesion less (φ)
backfill. It shows none of the data points
fall above the 1:1 correspondence line.
In this case, the calculated load values
7
TECHNICAL PAPERS
are an order of magnitude higher than
the measured value. As the mean of
load bias values is μQ = 0.68, hence,
it concludes that measured load values
(Q) are 68% of the calculated load
values (Tmax).
Fig. 3 Measured vs Calculated Load
values for λ = 1
based on calculated Tmax into two
or more groups, or filtering the data
(Bathurst et.al. 2008). However, this
will result in different resistance
factors for different load ranges and
thus complicates design. The strategy
ultimately adopted in the current study
to minimize load bias dependency was
to remove selected bias values. After
many attempts, the best filter criterion
for c-φ soil wall cases is to remove
all load bias values corresponding to
calculated Tmax < 0.5 kN/m (Bathurst
et.al. 2008) as shown in Fig 5.
3.1.2 Modified AASHTO Simplified
Method (λ = 0.30)
Fig. 4 shows, the current AASHTO
Simplified Model for calculation of
reinforcement loads for operational
(prepared) conditions. This model is very
poor for frictional (φ) backfill because
the current AASHTO simplified
model over-estimates the loads by a
factor of three. This deficiency can
be corrected empirically by using λ =
0.30 in Eq. 4 to compute Tmax. Also,the
data points fall above and below of
the 1:1 correspondence line. For this
case, mean bias value nearly equal to 1
whereas COV = 0.28.
Fig. 4 Measured vs Calculated Load for
λ = 0.30
3.1.3 Modified AASHTO Method (λ
= 0.15)
In order to extend the utility of the
modified Simplified Method to (c-φ)
backfill, a complication that arises
when all data points are considered is
an undesirable dependency between
load bias values XQ and calculated
load Tmax. This deficiency can be
corrected by dividing the load data
8
Fig. 5 Measured vs Calculated Load
for λ = 0.15
3.2Modified AASHTO Simplified
Method for Pullout Capacity
Models
According to AASHTO (2010) and
FHWA (2009) the ultimate pullout
capacity for sheet geosynthetics
(geotextiles and geogrids) is estimated
as,
Pc = 2 (F*α) σv Le
... (5)
An alternative expression that
used in practice is (Huang and Bathurst
2009),
Pc = 2 (Ψ tan φ) σv Le
... (6)
Where,
Le = anchorage length, F* and α =
dimensionless parameters, Ψ = tan
φsg/tan φ = dimensionless efficiency
factor, φsg = peak geosynthetic-soil
interface friction angle = δ. In the
FHWA document, the following
default values are recommended: αis
0.8 for geogrids and 0.6 for geotextiles,
whereas F*=2/3 tan φ (Huang et.al
2009).
Pullout Test Database:- The pullout
resistance data for 7 m high RE walls
containing surcharge load (q) varying
from 15 kPa to 55 kPa and angle
of internal friction (φ) for backfill
varying from 280 to 400, is available
from different case studies reported by
Huang and Bathurst (2009). The tests
were carried out in general conformity
with ASTM D 6706 (2007).
As reported by Huang et.al (2009),
there are five models used to measure
pullout capacity of geogrid in RS
walls which are listed in Table 1. Out
of these models, Model 1 corresponds
to the case where a single (average)
value of F*α is computed from a set of
pullout tests. Model 4 uses a bilinear approximation to the efficiency
factor Ψ. As demonstrated by Huang
and Bathurst, both models have strong
bias dependencies with normal stress
and therefore they are omitted from
the current study. Therefore, model 2,
model 3 and model 5 are used in the
current study.
Table 1 Pullout Models, their
Descriptions and their use in the
Current Study
Pullout
Model
Description
Model- 1
Average
measured F*α
First-order
approximation
to measured F*α
FHWA method
with default
values F*α =
0.8 x (2/3) tan φs
Bi-linear model
Model- 2
Model- 3
Model- 4
Model- 5
3.2.1
Non-linear
model
Use in
Current
Study
No
Yes
Yes
No
Yes
Model – 2
First-order approximation to measured
F*α:
A back-calculated values of F*α using
Eq. 5 are determined from a set of tests
performed on the same soil-geogrid
combination at different normal
stresses. Fig. 6 shows that measured
(Pm) versus predicted (Pc) resistance
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
values plot tightly around the 1:1
correspondence line having mean
and COV value of 1.03 and 0.13
respectively.
3.2.3 Model – 5: Non-linear model
The general form of the non-linear
pullout model proposed by Huang and
Bathurst (2009) is given by,
Pcorr = β (Pc)1+k
= β (2 σv Le F* α)1+k
... (7)
Where,
dimension-dependent terms β and
(1 + k) are equal to 5.51 and 0.629
when pullout capacity is computed in
units of kN/m (Bathurst 2009). Thus,
for the model 5, the mean is 1.12 and
COV is 0.50. From the above analytical
investigation, the results of mean and
Coefficient of Variation (COV) for
different Load and pullout capacity
models are tabulated as shown in
Table 2.
Table 2 Summary of Load bias statistics (XQ)
Parameter
Fig. 6 Measured vs Calculated Pullout
Resistance values for Model 2
3.2.2
SOIL TYPE
Frictional (φ- Soil)
Current Model
λ = 1.0
Model – 3
FHWA method with default values
F*α =0. 8x (2/3) tan φs
Model 3 corresponds to the current
FHWA (2009) geogrid pullout model.
However, unlike Model 2, soil-geogrid
pullout tests are not carried out. Rather,
the default value α = 0.8 is used and
F* is computed using φ of the soil.
Fig.7 shows, measured versus
predicted pullout resistance values.
Most of the data fall above the 1:1
correspondence line and the bias mean
is μR = 1.20. Hence, Model 3 underestimates the pullout capacity.
(c-φ Soil)
Modified Model
λ = 0.30
Modified Model
λ = 0.15
n (Number of data points)
50
50
50
μQ (mean)
0.68
1.02
1.08
COVQ
0.17
0.28
0.67
4 CASE STUDY
To incorporate the effect of Load and
Resistance Factors in design of RS wall,
a numeric example has been solved
using LRFD approach which was
already solved by Koerner et.al (2001)
using different ASD approaches.
Considering a RS wall as shown in
Fig. 8 having following properties,
Fig. 8 Measured vs Calc Pullout for
Model 5
Table 3 Bias Statistics for Different Pullout Capacity Model Types
Model
Fig. 7 Measured vs Calculated Pullout
Resistance values for Model 3
Description
Bias Statistics
Mean μR
COVR
2
First-order approximation to measured F*α
1.03
0.13
3
FHWA method with default values
(F*α = 0.8 x (2/3) tan φ)
1.20
0.59
5
Non- linear model
1.12
0.50
Table 4 Computed Resistance Factor φ for Pf = 0.01 (β = 2.33) and selected load factors γQ
Pullout Models
Load Factors Γq
Current Load
Model (λ = 1)
Φ-Soil
MODEL-2
MEAN μR = 1.03
COVR = 0.13
1
1.35
1.75
2
INDIAN HIGHWAYS, November 2014
1.18
1.6
2.07
2.37
Resistance Factor (Φ)
Modified Aashto Load Model
(λ = 0.30)
(λ = 0.15)
Φ - Soil
C- Φ- Soil
0.49
0.28
0.58
0.38
1.03
0.5
1.18
0.57
9
TECHNICAL PAPERS
Load Factors Γq
Pullout Models
Resistance Factor (Φ)
Modified Aashto Load Model
(λ = 0.30)
(λ = 0.15)
Φ - Soil
C- Φ- Soil
0.43
0.34
0.56
0.46
0.75
0.57
0.88
0.63
0.33
0.46
0.43
0.62
0.58
0.8
0.66
0.91
Current Load
Model (λ = 1)
Φ-Soil
MODEL-3
COVR = 0.59
MODEL-5
1.29
1.73
2.28
2.59
0.87
1.19
1.55
1.76
1
1.35
1.75
2
1
1.35
1.75
2
MEAN μR = 1.20
MEAN μR = 1.12
COVR = 0.50
Table 5 Summary of Recommended Resistance Factor Values for β = 2.33 and γQ = 1.35 using Current and
Modified AASHTO Simplified Method
Resistance (Pullout)
Model
Model- 2
Model- 3
Model- 5
Current AASHTO
Resistance Factor φ
Load Models
Modified AASHTO
λ=1
φ - SOIL
1.00*
1.00*
1.00*
λ = 0.30
φ - SOIL
0.58
0.56
0.43
λ = 0.15
c-φ SOIL
0.38
0.46
0.62
5RESULTS AND DISCUSSION
5.1External Stability Considerations
In the Modified Rankine’s approach,
the frictional force is computed by
taking into account only the weight
of reinforced soil mass i.e. it neglects
surcharge effect for conservative side.
Hence, it has less frictional resistance
thus FOS is less (2.07) for this
method.
Table 6 Comparisons of FS for External Stability
EXTERNAL STABILITY CONSIDERATION
Fig. 9 Typical RE wall Having Modular
Facing Block
Height of wall (H) = 7 m, Length of
wall (L) = 5 m, Surcharge (q) = 15
kPa, Reinforced soil properties: φr =
320, γr = 18 kN/m3 Backfill properties:
φb = 30º, γb = 17 kN/m3 Foundation soil
properties: φf = 30º, γf = 17 kN/m3
10
Sr. No.
STABILITY
CONSIDERATION
(FOS)
M.R
FHWA
NCMA
B.S CODE
LRFD
01
FS against sliding
(1.5)
2.07
2.11
2.87
2.15
1.70
02
FS against capacity
3.59
3.66
5.53
3.17
2.25
03
FS against
overturning
( ≥ 2.0)
3.63
N.A
4.93
5.52
3.57
In BS Code approach, the frictional
coefficient is taken approximately
equal to 1/3 to 2/3 of tan φ where,
φ is angle of internal friction hence,
more FOS (2.15) as compared to
Modified Rankine’s approach. In LRFD
approach, the resistance is reduced
whereas the load effect is increase as
explained earlier. Therefore, it has
least factor of safety than other ASD
approaches (1.70). The coefficient of
friction in NCMA approach depends
upon types of the soil which controls
the sliding (reinforced, drainage and
foundation) as given by Koerner et.al.
2001. Hence, frictional resistance of
NCMA approach is more as compared
to FHWA and Modified Rankines
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
approaches, hence more FOS (2.87).
In Modified Rankine approach,
overturning moment can be computed
by adding moments due to earth
pressure and surcharge loading for
safer side.
Table 7 Comparison of FS for External Stability Consideration
(Eccentricity Consideration)
External Stability Consideration
Stability Consideration
M.R
FHWA
NCMA
B.S
CODE
LRFD
Eccentricity (m) ( e ≤ B/6)
0.64
0.63
0.42
0.64
0.70
Also, total vertical load (ΣW) is the sum
of weight of soil mass and surcharge
loading therefore eccentricity is
maximum and also equal to BS Code
approach because it is attributed to the
ratio of difference between resisting
moment and overturning moment
to total vertical load. Thus, the
eccentricity is given by, e = (B/2) - x,
hence e is more (0.64m) as compared to
Modified Rankine approach. In LRFD
approach, the location of resultant is
at middle half of the base. Therefore,
gets decrease and eccentricity increase
(0.70 m).
5.2Internal Stability Considerations
5.2.1 Tensile Failure
Fig. 10 Factor of Safety Against Tensile Rupture
In the Modified Rankine approach, the
vertical stress (σv) is due to self weight
of reinforced soil and surcharge effect,
hence it is more. As the design strength
(Tdes) is a function of vertical stress, it
is also more and thus FOS =
is less.
In BS Code approach, the maximum
vertical stress (σvmax) is given by sum of
direct and bending stress which is less
and hence FOS is more as compared to
Modified Rankine’s approach. In LRFD
approach, the empirical adjustments
are made by using bias factor λ to the
tensile load models to match measured
reinforcement loads in RS walls under
operational conditions. Therefore,
incase of LRFD approach FOS is most
as compared to other ASD approaches
as shown in Fig 1.
The active earth pressure distribution
on RS wall is triangular in nature
having zero pressure at top and
linearly increases to maximum at
bottom. Therefore, the vertical spacing
of geogrids is minimum at bottom and
gets increases from bottom to top.
As the tensile force is a function of
vertical spacing of geogrid layers, it
is maximum at top gets decreases with
depth of the wall. Therefore, the FOS
is also more at the top of the wall and
gets decrease continuously with depth
of the wall. The trends of FOS for all
five methods are approximately same
whereas trend of Modified Rankine,
FHWA and NCMA approach matches
with each other as shown in Fig 10.
The FOS for LRFD approach is more
as compared to other approaches may
be because in LRFD approach, the
maximum tensile force gets decrease
due to bias factor λ for Modified
Simplified AASHTO method for Load
model.
5.2.2 Pullout Failure
In Modified Rankine approach, the
pullout capacity (Pc) can be computed
by assuming interaction coefficient
and coverage ratio, due to this pullout
capacity gets decrease and hence
FOS also gets decrease. In BS Code
INDIAN HIGHWAYS, November 2014
approach, to compute Pc, the average
stress at resistive zone is assumed
instead of maximum stress and hence
FOS is more as compared to Modified
Rankine approach. In LRFD approach,
to compute pullout capacity, five
deterministic models are used. The
resistance factor φ = 0.58 is taken to
compute pullout capacity in the current
study from model 2 which requires
actual laboratory pullout tests. Hence,
for LRFD approach, FOS may be least
for all layers of RS walls as compared
to ASD approaches.
Fig. 11 Factor of Safety against Pullout
Failure
The Rankine’s failure plane is inclined
which makes an angle of (45+φ/2)
with horizontal hence effective length
is lesser at top and gets increase from
top to bottom. As pullout capacity
is the function of effective length,
pullout capacity as well as FOS is less
at top and more at bottom as shown
in Figs. 11 and 12 shows the graph
between FOS against pullout failure
on normal scale versus FOS against
tensile rupture on semi-log scale for
all five approaches together.
Fig. 12 Factor of Safety Against Pullout Failure vs.
Factor of Safety against Tensile Rupture
Fig. 12, reveals that the trend of
Modified Rankine, FHWA and NCMA
11
TECHNICAL PAPERS
approaches are approximately parallel
to each other. On the other hand,
the trend of BS Code and LRFD
approaches are approximately parallel
to each other. The equations of the
trendlines for various approaches
and their R2 values are tabulated in
Table 8.
Table 8 Equations of the Trend Lines and their R2 Values for Various Approaches
Design Approach
Equation of Trend Lines
R2 Value
Modified Rankine
FSPu = -33.6 ln(FSTR) + 37.47
0.940
FHWA
FSPu = -31.9 ln(FSTR) + 39.02
0.906
NCMA
FSPu = -47.0 ln(FSTR) + 54.26
0.906
BS CODE
FSPu = -14.1 ln(FSTR) + 28.16
0.947
LRFD
FSPu = -13.0 ln(FSTR) + 30.46
0.977
Table 8 consists of various equations
which reveals that that if FS against
tensile rupture is known for any
RS wall having 7 m height and
same properties and environmental
conditions as mentioned in current
study then FS against pullout failure
can be computed for these walls.
In the Table 8, the equations are
used only for that RS walls which
has same dimensions, same material
properties and same environmental
conditions as that of RS wall used in
present study. Hence, these equations
are not universal equations but can be
converted into universal equations by
further work.
6 CONCLUSIONS
1. The FS against Pullout failure
varying from 35.20 to 22.44.
2. Depending on the reinforced
soil type (frictional & cohesivefrictional) and the pullout model
adopted, the resistance factor
(φ) varies in the range of 0.38 to
0.62. While these values are lower
than φ = 0.90 recommended by
AASHTO.
3. An important practical benefit
of using Model 2 (First-order
approximation to measured F*α)
with actual laboratory pullout data
over the default Model 3 (FHWA
method with default values F*α =
0.8 x (2/3) tan φs) and non-linear
Model 5 is that the Model 2 allows
a higher resistance factor (φ) to be
used for design; the result is shorter
reinforcement lengths and hence
more cost-effective wall design
outcomes.
4. New generated equations reveals
that that if FOS against tensile
rupture is known then FOS against
pullout failure can be computed.
5. Also the value of F*α is obtained
without performing actual pullout
test.
6. As pullout test is costlier and
difficult to performed so current
study gives various equations
and from which FS against
pullout failure is obtained without
performing actual pullout test.
7 ACKNOWLEDGEMENT
The M.Tech dissertation work is
carried out at Department of Civil
Engineering, College of Engineering,
Pune during academic year 2011-12.
Director, COEP has acknowledged
giving permission for publishing this
work.
ANNOUNCEMENT
Sales Centre of IRC is being operational at Bhabani Bhavan, Kolkata (West Bengal) from
26th September, 2014. The endeavor of IRC is to enhance its reach to the Engineering Fraternity.
The esteem members of IRC are requested to take advantage of this new initiative.
The contact address of Sales Centre of IRC is Bhabani Bhavan, New Building, 7th Floor,
Kolkata-700 027 (West Bengal), Tel: 09874462649 E-mail: [email protected]
OBITUARY
The Indian Roads Congress express their profound sorrow on the sad demise of Late Shri Suresh
Mukhdekar, Resident of 1-2-5-35, Uday Nagar, Nanded (M.S.). He was an active member of the
Indian Roads Congress.
May his soul rest in peace.
12
INDIAN HIGHWAYS, November 2014
Assessment of Suitability of Lime-Laterite Soils in the Construction
of Road Base
P.G. Bhattacharya*, T. Ghosh** and R. Paul***
ABSTRACT
Highway pavements need good quality paving materials having adequate strength and durability characteristics. With petroleum
prices rising sharply, bitumen is no longer a cheap material and therefore bituminous macadam and other bituminous materials cannot
be considered as economical road bases at present. But highway activities have increased manifolds in recent times due to rapid
industrialization and urbanization. As a result, quality paving materials have really become scarce and costly. Under the circumstances
use of locally available indigenous materials after suitable treatment or otherwise, is the only solution to meet the growing demand
of road construction and replace the costly paving materials being used. The suitability of laterite soils for use as road bases after
treatment with lime and coconut fibre is considered fruitful in this regard. A good road base made up of bound material should
have adequate flexural fatigue strength and durability, particularly when the material is applied in the upper layers of the pavement.
Addition of lime in favourable climate in small amounts, 3 to 7 percent by weight, to reactive soils brings about a decrease in density,
a reduction in plasticity, an improvement in workability and an increase in soil strength. The pozzolanic reactions take place between
lime and soil silica or alumina and form various cementing agents, primarily silicates and aluminates of calcium responsible for
development of strength.
1 INTRODUCTION
Laterite
soils
are
essentially
products of tropical and sub-tropical
weathering. The chemical composition
and chemical characteristics of these
products are influenced by the degree
of weathering to which the parent
material has been subjected. Laterites
are products of intense sub-aerial rock
weathering, whose iron and aluminium
content is higher and silica content is
lower than in merely kaolinised parent
rocks. They consist predominantly of
kaolinite, goethite, hematite, gibbsite
and quartz. A laterite profile comprises
all stages from parent rock to the
surface and therefore laterite soils
cover a wide range of materials, from
earthy to rocky. They are commonly
found as reddish pedogenic surface
deposits and are popularly known as
‘red tropical soils’. The location and
distribution of laterite materials have
been associated with temperature
and rainfall conditions characterizing
the earth’s surface between latitudes
35ºN and 35ºS (1). Of this, nearly
one-third of the total land surface of
the earth is contained within the huge
belt bounded by the tropics of cancer
and capricorn. ‘Red tropical soils’
are dominant feature of the landscape
within this area (2). In India, the coastal
part and its adjoining interior are areas
of known laterite soil occurrence and
exhibits distinctive distribution of
these soils.
2LATERITE FORMATION
Laterite soils are formed in humid
tropical and sub-tropical areas of South
America, Africa, India, Indonesia
and Australia. Essentially, they are
products under certain weathering
conditions. Tropical weathering and
laterisation involve chemical and
physico-chemical alteration and/
or transformation of primary rockforming minerals into materials rich in
clay minerals and laterite constituents
that is iron, aluminium, titanium and
manganese. High content of laterite
constituents in relation to other
constituents is the important feature of
all laterite soils.
There are three stages in the process
of weathering and laterisation, the
first stage called decomposition, is
characterised by physico-chemical
break-down of primary minerals
whereby constituent elements such as
SiO2, Al2O3, Fe2O3, CaO, MgO, K2O,
Na2O etc., are released and appear
in simple ionic forms (3). Physical
weathering involves fragmentation
of parent rocks into end products
consisting of angular bocks, cobbles,
gravel, sand, silt and even to claysized rock flour as a result of periodical
temperature changes, erosional forces,
and the disintegrating action of plants
and animals. Chemical weathering, on
the other hand, is the decomposition of
rock and formation of new minerals as
a result of action of water, air, organic
acid etc., that enter into chemical
reactions with the primary minerals.
The predominance of chemical or
physical weathering depends on
climatic conditions, mainly rainfall
and temperature (4) and wetter the
area, more intense is the weathering.
Laterisation is the second stage, which
involves leaching under appropriate
drainage conditions, of combined silica
and bases and the relative accumulation
or enrichment of oxides and hydroxides
of sesquioxides, mainly Al2O3 and TiO2
from external sources. Leaching is the
most important phenomenon in laterite
soil forming process; the percolating
water is the most active agent in soil
profile development (3, 5, 6). The
soluble constituents are released by the
hydrolyzing processes and removed by
repeated flushing by rain water resulting
in weathering reactions to proceed
towards completion. According to
Ahn(7), chlorides and sulphates, being
very soluble are quickly removed in
* Emeritus Professor, ** Assistant Professor, *** Assistant Professor, E-mail: [email protected] (Department of
Civil Engineering, Hooghly Engineering & Technology College, Hooghly, W.B.)
INDIAN HIGHWAYS, November 2014
13
TECHNICAL PAPERS
the first stage of weathering and then
calcium, sodium, magnesium, and
potassium with subsequent removal
of combined silica from silicates. The
most resistant compound to leaching
are the sesquioxides of iron and
aluminium, Fe2O3 and Al2O3. Therefore
slightly to moderately leached soils
may lose all the mobile elements in the
first and the second stages but retain
all or most of the combined silica and
sesquioxides. In extreme weathering
condition, silica is removed more and
with further weathering, leaching and
translocation, the quantity of silica is
reduced and the proportion of iron and
aluminium sesquioxides is increased.
Thus, more the leaching, more is
the probability of weathering and
laterisation towards formation of true
laterites.
The third stage is the partial or complete
dehydration and sometimes hardening
of the sesquioxides-rich materials and
secondary minerals. In the process
of hydration colloidal hydrated
iron oxides lose water resulting in
concentration and crystallisation
of the amorphous iron colloids into
dense crystalline iron minerals in the
sequence : Limonite, goethite, and
goethite with hematite to hematite as
observed by Hamilton (8) and other
researchers.
3LITERATURE REVIEW
Depending on the hardening property,
Buchanan (9) was the first to introduce
the term laterite and define it as a
ferruginous, vesicular, unstratified,
porous material with yellow ochres
due to high iron content occurring in
Malabar, India. The freshly dug material
was soft enough to be readily cut into
brick block with an iron instrument
but rapidly hardened on exposure to
air. Wooltorton (10) describes it as
“a very hard homogenous vesicular
massive clinker like material found in
hilly tropical countries, in which the
structural framework is of red hydrated
ferric oxides and the vesicular in fill is
14
of soft aluminium oxides of a yellowish
colour; or a similar profile of softer
material which hardens on extraction
and exposure.” Fermor (11) defines
various forms of laterites on the basis
of the relative contents of the so-called
laterite constituents (Fe, Al, Ti and
Mn) in relation to Silica. Winterkorn
and Chandrasekharan (12) recongnised
the presence of iron in lateritic
soils as the most important factor in
influencing the engineering properties
of these soils. Alexander and Cady (13)
summerised the physical, chemical and
morphological concepts of laterites
proposed by various researchers in
the following lines: “Laterite is a
highly weathered material, rich in
secondary oxides of iron, aluminium
or both. It is nearly void of bases and
primary silicates, but it may contain
large amount of quartz and kaolinite.
It is either hard or capable of hardening
on exposure to wetting and drying.
Remillon (14) has named the zone
of leaching as horizon A, the zone of
accumulation as horizon B, the zone of
weathering as C and the sound parent
rock D. The other method of naming
is according to the morphological
characteristics by which soils are
identified. Thus horizon A represents
the generally dark humus stained top
soil, B2 the laterite horizon of iron and
alumina crusts, B1 the zone of mottling
having evidence of sesquioxides
enrichment, C the pallid or leached
zone and D the sound parent rock. Rao,
Datta and Neyogi(15) made a study of
laterite soils around Kharagpur, India
under different land use with respect
to their mineralogical composition and
some chemical and physio-chemical
aspects. They identified two distinct
soil horizons: (a) laterite hard crust
and (b) laterite soil.
4 ASSESSMENT OF SUITABILITY
Suitability of a material for engineering
purposes can be tested on the basis
of strength and durability. The direct
way to recognize whether a soil for
use in pavement layers is suitable or
unsuitable or can be made suitable
by treatment is possible by studying
the various strength characteristics.
The laterite soils vide Table 1 for
physical properties; have two distinct
soil horizons, the laterite hard crust
and the underlying mottled zone.
The air-dried soil without any
treatment gave C.B.R. values under
modified AASHTO compaction as
low as 3.42 to 3.50, which further
decreased on soaking. Five percent
addition of hydrated lime, containing
nearly 64 percent calcium oxide
increased the values 10 times or
so and 4 days soaking further
improved the results. This, therefore,
indicated that the soils were limereactive in nature and there was
scope for detailed investigation of the
material-strength based on compaction,
curing and mix proportion. It has
been almost universally accepted
that addition of lime in favourable
climate in small amounts, 3 to 7
percent by weight to reactive soils
produces a marked improvement
in
the
engineering
properties
(16, 18). This brings about a reduction
in plasticity, an improvement in
workability and an increase in soil
strength. The degree to which the lime
will react with soil, however, depends
on such variables as the quantity of
lime, soil type, the compaction, and the
length of time the lime-soil mixtures are
cured and also the curing temperature
of accelerated curing. By accelerated
curing it has been meant that curing
has been done in oven at controlled
temperature. Anday (22) and Thompson
(23) both cured lime-soil specimens at
50ºC to obtain very quick response
in development of strength. This was
taken as the guidance for selecting
50ºC as the limiting temperature. The
laterite materials as used, having found
to respond favourably to lime treatment
on preliminary investigation giving
increased C.B.R., were subjected to
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
unconfined compression to determine
quantitatively the beneficial effects of
the treatment by obtaining strengthdensity relationship, by working out
optimum composition of the mix, and
by comparing normal laboratory moist
curing with accelerated oven curing.
Compaction is commonly used to
improve the strength of the pavement
layers, bound or unbound. The usual
compaction variables are water
content, dry density and compacting
work. For compaction, dry of optimum
and also the optimum dry density, is
a function of both water content and
compactive work, and for compaction
wet of optimum, it is mainly governed
by water content (19). However,
whatever be the compaction variables,
dry density is finally attained has
become the basis of comparison
(20). Compaction was identified
at three levels, light, medium and
heavy. Standard proctor compaction
density was taken as a measure of
light compaction, modified AASHTO
compaction density as a heavy, and
the mean of the two, approximated
medium compaction. Specimens of
different densities could be obtained by
varying the moulding water at constant
compactive effort, or by applying
different compactive effort at the same
moulding water, or by compacting pre-
determined weight of wet materials
to constant volume, weight being
determined on the basis of desired
moisture content and dry unit weight.
It is fairly common knowledge that
the strength of a material particularly
a cemented material is dependent
to a great extent on its dry density.
Whatever be the factors contributing to
dry density, dry density is the ultimate
state attained by a specimen in a
compaction phenomenon. Therefore
statistical correlation between strength
and density of compacted specimens
of lime-laterite mixtures, if available,
should yield a relationship taking
into account other factors associated
with compaction giving a relationship
general in nature between strength
and density. Strength is however a
function of lime dose also. For this
reasons specimens were prepared at
different dry densities, low, medium
and high, at each of the lime per cent
added, 2.5, 5.0 and 7.5 by weight
of air-dry soil. The samples were
cured in oven at 50ºC ± 1ºC for 3
days(16). Regression relationships
were obtained for each of the lime per
cents and optimum percentage of lime
for maximum strength benefit was
worked out(16). Another four groups
of specimens prepared with optimum,
5 per cents of lime, but of different
densities and classified on the basis
of four moist curing periods of 15day, 30-day, 45-day and 60-day were
tested in unconfined compression and
the results correlated to develop four
prediction equations corresponding
to four curing periods. The number
of days of moist curing equivalent to
3-day oven curing at 50ºC were worked
out by comparing these relationships
with that of oven cured specimens
with 5 per cents of lime. The strengthdensity relationships for four moist
curing periods were used to obtain
compressive strength at different days
of curing and at different densities.
Finally multiple regression analysis
was made to develop prediction
equation for unconfined compressive
strength on dry density and number of
days of moist curing.
The particle size distribution of lateritic
soil is given in Table: 2.
The unconfined compression test
results gave considerable strength
increase. 7-day UCS values for cement
stabilized silty clay (L.L = 74%, PL
= 28%) compared with lime laterite
soils are given below in Table 1, for
5%of stabilizer (24) which shows that
Lime laterite soil with 5% lime yield
better strength at Modified Proctor
compaction.
Table 1. 7-day UCS Values of Lime Laterite Soil and Cement Soil Mixtures of Different Densities
% of
Stabilizer
Stabilizer
5%
UCS Value (MPa)
Standard
Modified
Lime
0.58
2.15
Cement
1.10
2.10
But a pavement is made up of layers
of different materials and when the
overlying layers have higher moduli of
elasticity than the underlying layers,
tensile stresses are developed at the
interfaces of the stiff layers. Therefore,
to incorporate the lime-soil mixtures
in the upper layers of the pavement
structure, study of tensile strength
characteristics is of considerable
importance. Thompson has shown that
in pavement applications, lime-soil
materials will be subjected to repeated
flexural stresses and strains and
therefore their flexural strength and
fatigue response are more important
considerations than the shear and
compressive strength of the materials
(18, 21). Therefore due importance was
given to the flexural and fatigue flexural
aspects of lime-laterite materials, plain
and reinforced with coconut fibres.
INDIAN HIGHWAYS, November 2014
The optimum composition of the mix
was determined from the unconfined
compressive strength studies. This
composition was then evaluated for
flexural and fatigue flexural strength
of the material.
Beam specimens of different densities
were subjected to flexure loading
until failure. The test results were
correlated to develop regression
equation between modulus of rupture
15
TECHNICAL PAPERS
and dry density. Load deflection curve
were plotted to obtain elastic moduli
identified as constant strain-rate
modulus when the load was applied at
1.25 mm per minute and static modulus
when the load was increased in steps,
each step remaining constant for some
time until the deflection ceased to
increase. Coconut fibre at lengths of 2
and 4 cm and at 0.2, 0.4, 0.6 and 1.0
per cents by weight of air-dry limelaterite mixtures were used to reinforce
the plain mixes. The effects of such
addition were studied by developing
regression equations between modulus
of rupture and dry density for limefibre-laterite mixtures for each per
cent of fibre added. The variation of
strength with fibre per cents indicated
that 0.6 per cent of 2 cm fibres
increased flexural strength from 7 to
25 percents, depending upon whether
the comparison was made with respect
to the unconfined compressive strength
at the modified AASHTO compaction
density of lime-laterite or lime-fibre
laterite mixtures. The later was about
95 percents of the former. The flexural
moduli of lime (5 per cent)-fibre
(0.6 and 1.0 percent 2 cm)-laterite
mixtures were greater than those of
lime (5 percent)- laterite mixtures at
heavy compaction.
Table 2 Physical Properties of Tested Laterite Soils
Property
Textural Composition: Percent Passing
4.75 mm
2.36 mm
1.18
0.600 mm
0.425 mm
0.300 mm
0.15
0.075
Gravel (>2 mm)%
Sand (2-0.074 mm)%
Silt (0.074-0.005 mm)%
Clay (<0.005 mm)%
Specific gravity
Liquid limit (%) with 0% and 5% lime
Plastic limit (%) with 0% and 5% lime
Plasticity index (%) with 0% and 5% lime
Soil classification:
Textural
AASHTO
Unified
5 Correlation
Between
Unconfined
Compressive
Strength,
Dry
Density
and Curing Time of LimeLaterite Soils
The main purpose of the unconfined
compressive strength study was
to examine variation of strength
with density and the possibility of
establishing correlation between the
variables. Strength determination were
made on 3-day oven cured specimens at
50ºC containing 2.5, 5.0 and 7.5 percent
of lime and on moist cured specimens
16
Value
100
98.98
96.81
89.44
81.08
75.87
57.70
56.09
1.02
42.89
47.40
8.69
2.67
30.95 and 30.45
18.37 and 23.20
12.58 and 7.25
Loam
A-6(12)
CL
at ambient laboratory summer
temperature with 5 percent of lime
but cured over 15, 30, 45 and 60 days
(16, 17). The unconfined compressive
strength determined for each sample
in each group has been plotted against
corresponding dry density. The data
are fitted in a least square polynomial
regression programme. The following
equations
give
the
functional
relationships between unconfined
compressive strength, σu (N/mm2) and
γd (Kg/m3) for oven cured specimens
with 2.5, 5.0 and 7.5 percents of
lime respectively. The coefficients
of correlation are respectively 0.96,
0.92 and 0.93 and the F-test values are
significant at α= 0.01.
σu = –11.42 + 0.0072 γd
σu = –15.32 + 0.0094 γd
σu = –11.17 + 0.0074 γd
... (1)
... (2)
... (3)
Again, the following equations give
the same relationships for four groups
of moist-cured specimens according to
days of curing 15, 30, 45 and 60 days.
The coefficients of correlation are
0.92, 0.90, 0.90 and 0.91 respectively
and the F-test values are significant at
α = 0.01.
σu = –11.48 + 0.0069 γd
... (4)
σu = –18.17 + 0.0106 γd
... (5)
σu = –14.38 + 0.0091 γd
... (6)
σu = –14.34 + 0.0093 γd
... (7)
Finally, multiple regression analysis
has been made for unconfined
compressive strength on dry density
(γd) and days of curing (Z in days) and
the following relationship obtained
with 16 degrees of freedom.
σu (N/mm2) = –16.0548 + 9.0 x 10–3 γd
+ 0.0382 Z
... (8)
Fig. 1 Regression Curves for Unconfined
Compressive Strength on Dry Density of
Lime-Laterite Mixtures
Fig. 2 Regression Curves for Modulus of
Rupture on Dry Density of Lime-Laterite
and Lime-Fiber-Laterite Mixtures
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
Table 3 Regression Equations
Description
Lime %
3-day
Oven
Cured
2.5
5
7.5
15-day
5 (Moistcured)
Constants of Equation
β1
β0
-11.4209
7.2195
-15.3158
9.4342
-11.1727
7.4257
Equation
No
1
2
3
unconfined compressive strength
(σu) and dry density (γd)
σu = β0 + β1 x 10-3 γd
unconfined compressive strength
(σu) and dry density (γd)
σu = β0 + β1 x 10-3 γd
-11.4808
6.9566
4
30-day
-18.1696
10.6185
5
45-day
-14.3795
9.1077
6
60-day
-14.3372
9.2573
7
6 CONCLUSIONS
The following conclusions are drawn
in respect of studies that could be made
for the assessment of suitability of
lime – laterite soils in the construction
of road base and also in sub-base.
Static Loading Tests
Static tests at 1.25 mm per minute
rate of loading were performed in
the laboratory to investigate the basic
behaviour of cured lime-laterite soil
specimens in simple axial compression
and flexure for the following specific
purposes:
A. Unconfined Compression Test
1. To study the relationship between
Unconfined Compressive strength
and dry density of oven cured
cylindrical specimen at various
percentages of lime.
2. To
determine
whether
the
various
laterite
soils
collected from various locations in
the neighbourhood could develop
equivalent strength.
3. To determine the optimum
percentage of lime needed
to
stabilize
laterite
soil
based on compressive strength
characteristics.
4. To
study
the
additional
improvement achieved by higher
density specimen.
5. To determine the equivalent of
3-day oven curing at 50ºC in terms
of normal laboratory moist curing
during the summer months having
mean daily temperature of about
32ºC.
B. Simple Flexure Test
1. To study the relationship between
the ultimate flexural strength in
terms of modulus of rupture and
dry density of oven-cured limelaterite and lime-fibre-laterite soil
beams.
2. To study the effect of coconut fibre
in improving the flexural strength
of the stabilized mixtures.
3. To determin e the optimum
percentage of fibre from the point of
view of strength and workability.
4. To determine the static and constant
strain rate flexural modulus.
Repeated Loading Tests.
Repeated simple loading tests
were conducted in the laboratory
to investigate the flexural fatigue
response of lime-laterite soil beams
with and without fibre for the following
purposes:
1. To study the relationship between
flexural fatigue life and stress ratio
for lime-laterite and lime-fibrelaterite soil mixtures at different
compactions, light, medium and
heavy, identified by dry density of
specimens.
2. To study the relationship between
flexural fatigue life and the ratio of
dry density to applied flexural stress
for lime-laterite and lime-fibre-
INDIAN HIGHWAYS, November 2014
Relationship between
laterite soil beams compacted at
different densities resembling light,
medium and heavy compaction.
3. To study the relationship between
repeated flexural stress and
maximum (central) beam deflection
for both the types of mixtures at all
the three compactions.
4. To study the relationship between
dynamic flexural modulus and
dry density over light to heavy
compaction
for
lime-laterite
mixtures with and without fibre
reinforcement.
5. To develop fatigue-life curves of
104 to 108 applications to cater for
low to heavy volume loads for both
the materials based on dry density
or dynamic flexural modulus and
repeated flexural stress, to be used
for design purposes of pavement
bases with such materials.
6. To develop relationship between
fatigue-life, dynamic flexural
modulus and repeated flexural
stress to determine flexural strain
in lime-laterite and lime-fibrelaterite soil bases.
7. To make a comparative study
of the flexurally loaded plain
and fibre-reinforced stabilized
mixtures and to evaluate the
merit of fibre reinforcement in the
fatigue characteristics and dynamic
flexural modulus of the materials.
17
PEDESTRIAN SAFETY IN URBAN SITUATION
Er. V. Dinesh Kumar* and Er. S. Satheesh**
ABSTRACT
Pedestrian is the most Vulnerable Road User amongst all categories of the road users. Incidentally, he is the hapless victim of Road
Traffic Accidents (RTAs). Statistics also reveal that quite often, it is economically deprived, elderly citizen who fall a prey to accidents.
Conditions those are not conducive for walking alongside, across, the carriage-way in urban situations, often results in conflicts between
Vehicles and Pedestrian, resulting in fatalities, involving pedestrian. Infrastructural facilities that patronise the pedestrian, available
at important locations along the road environment, would encourage the pedestrian to use the same with confidence, reliability and
safety. But, it is equally important that such facilities should promote and encourage the usage by the end users. Encroachments,
absence/discontinuity of facility, importance to the Vehicle mobility, and extensive use of private transport, unsafe environ for women,
elderly, and children all discourage the patronage of the pedestrian facility. Case-studies do depict situations which many a times,
work against the design of safe passage and mobility of pedestrian. Study aims at mapping the conditions at site and comparing it
with standards. The objective information on the contribution of an item/part of the facility towards causing an accident, weighted,
analysed. The analysis aids at remedial measures that may ensure safety of the pedestrian.
1 INTRODUCTION
Pedestrian is an in separable component
of “Road Traffic” Incidentally, a
pedestrian is the most vulnerable end
Road user most accidents between
Road involving motor vehicle occur
whenever there is conflict.
Walking, which is the traditional mode
of transport carrying a high risk of
injuries/Death in our nations street
in highways. The National Highway
Traffic
Safety
Administration
(NHTSA) reports that an average a
pedestrian dies from a motor vehicle
collusion every 113 minutes and
every pedestrian is injured in a traffic
incident about every 8 minutes.
National Statistics:
While on the one hand, walking is
encouraged as healthy habit, also a
cheap eco-friendly modes of transport
accessing the other modes of transport,
yet if the conflict are not avoided
naturally, the pedestrian is hapless
victim of a Road Traffic Accident. A
scenario of Pedestrian fatalities is the
state of Tamil Nadu is best explained
as per the Figure below.
About the Pedestrians:
A pedestrian is a person travelling on
foot, whether walking or running. In
some communities, those traveling
using roller skates, skateboards, and
similar devices are also considered to
be pedestrians. In modern times, the
term mostly refers to someone walking
on a road or foot path, but this was not
the case historically. (Source : Road
Vehicle Accident Reconstruction by
Rao V Dukkipati)
Pedestrian categories:
these requirements would also
satisfy the needs of all other
users, especially older people,
people with heavy shopping/
young children, and people with
temporary impairments or low
levels of fitness.
● Child – requires a high level
segregation from motorized traffic
and/or other measures to reduce the
dominance of motor vehicles, such
as speed reduction, together with
good passive surveillance from
other users. These are important
factors where children and young
people make independent journeys
to school.
As shown in the above list, the
categories distinguish between the
differing priorities assigned to various
aspects of the road – for example,
Several methods of categorizing
pedestrians are in use. For example,
categorization by trip purpose and
abilities is one such method, in which
the categories and comments on their
requirements are as follows:
● Commuter – prefers a fast
direct route between home and
work or when accessing public
transport, regardless of quality of
environment.
● Shopper/leisure walker – looks
for ease of access, attractive
retail environments and attractive
routes.
● Disabled person – requires level,
clearly defined easy access and
careful attention in the design
and placement of street furniture,
including resting points. Satisfying
* Asst. Engineer (H), Traffic Lab, ** Deputy Director, Traffic Lab, Highway Research Station, Chennai
18
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
safety versus directness - for users
with different requirements due to their
journey purpose, level of experience
i.e. physical ability. The design of the
most appropriate infrastructure must
take account of the anticipated type of
user.
Pedestrian facilities:
The pedestrian facilities mainly
requires infrastructure which should
aim at delineating the pedestrian
movements from the stream of traffic
flow. Such a delineation aims at
the reducing the conflicts between
the vehicle and the pedestrian. The
foremost among the following of the
provision.
Pedestrian Foot ways:
An adequately designed pedestrian
footway goes a long way in segregating
the vehicular and pedestrian traffic and
affords a sense of safety and protection
to the pedestrians. For being effective,
the foot ways should be raised above
the road level and must have a surface
which will attract the pedestrian to use
it.
Pedestrian Subways:
A much preferred facility by a
pedestrian in contrast to a foot over
bridge. The sub ways shall have a
gentle gradient with sufficient width to
meet the peak hour demand.
Foot over bridge (FOB):
Facilities provided to cross over the
road section safely above grade with
the flight of stairs leading to the FOB
IRC standards suggest a slope of 5%
on foot print ramp with landings.
Minimum width of FOB’s suggested
is 1800 mm. Escalators and ramps
encourage pedestrian to use the cross
over facilities.
Criteria for pedestrian facilities
design:
Comfort and speed of travel – for any
given purpose the route must offer an
acceptable travel time to and usually
from the destination,
● Safety – the route and its individual
crossings and other conflict points
with vehicular traffic as well as
the surface quality of the walking
surface should be designed to enable
pedestrian to pass with minimum
risk of injury or intimidation;
● Reliability – the route must be
available at all times and in all
weather conditions if it is to be
used frequently; and,
● Security – freedom from crime and/
or intimidation is a key requirement
for a route to be used reliably.
Additionally, a pleasing environment,
i.e. greenery etc. and a route of interest
will greatly add to the likelihood of
a route being used. Of the matters
mentioned
above,
appropriate
geometric design of the facilities is
a key factor in assuring convenience
and safety. Clearly, concerns about
reliability and security (freedom
from crime) are of importance also
and matters related to these issues
will often overlap those of safety and
convenience.
Case Studies :
Research study have been carried-out
to assess the pedestrian Vulnerability
at select 15 locations within urban
limits of Chennai city- as a Case- study
model, where the pedestrian density
was higher.
The Study involves the dedicated Data
collection at field regarding,
● Vehicular movement
● Pedestrian movement
● Pedestrian facility mapping
● Accident analysis based on
RADMS data
● Rating the lack/Preserve of facility
● Comprehensive analysis of the
Pedestrian Vulnerability (Exposure)
to road Traffic Accidents (RTA’s)
● Suggestion of suitable remedial
measures to alleviate field
situation
Corridor: NSC Bose Road, Rajaji
Salai, Sir Muthusamy Iyer Salai,
INDIAN HIGHWAYS, November 2014
Esplanade Road & Parrys, in
Chennai City
Location: Broadway & Extended
Broadway
Date
of
Survey:
01.02.2012,
29.06.2012 & 30.01.2013
Locational Details:
● Part of the original Black Town
or George Town area of Chennai
city. Dates back to the 20th and 21st
centuries, where this was the sole
central commercial hub of the city
● Zone provides better connectivity
to all parts of the city and once had
the large Bus Stand for the City
providing connectivity to all parts
of the State & neighboring States.
● The NSC Bose road starts from
the Flower Bazaar Police Station
at the Western End and runs up
to the junction of Rajaji Salai and
Kamarajar Salai at the eastern end,
popularly known as Parry’s corner
● NSC Bose Road is proximal to the
Central Railway Station, the Bus
Terminus for intra-city services to
the urban and suburban limits of
Chennai and hence a significant
location.
● The Four-legged intersection near
the entrance of Madras Law College
is a junction of NSC Bose Road
with Prakasam Salai (Broadway)
and Esplanade Road controls the
traffic by signals
● The Eastern end of the Road is lined
up with the Madras High Court
and the Western end is lined up
Government Offices, Commercial
establishments, BSNL Exchange,
Bus Terminus – all making it one
of the busiest roads in the city.
● Busy Corridor for most part of
the day/month/year ; Chennai’s
first Largest Bus Terminus ; First
Business District of Chennai.
● Though the bus services for intercity and major part of intra-city
had been shifted to Koyambedu,
a part of intra-city services are
plying from Broadway Terminus
thereby its function remains.
19
TECHNICAL PAPERS
● Though the Flower, Fruit and
Vegetable markets had been shifted
to Koyambedu, Chennai, this part
of the city still regains the business
activities and is busy in selling the
products from the streets adjoining
NSC Bose road like, Anderson
street, Bunder Street, Narayana
Mudali Street, Stringer Street etc.,
● Considered to be the shopping and
commercial hub – with Stationeries
wholesale at Anderson street,
Clothes Wholesale merchandise
at Bunder Street, Pharmaceuticals,
Chemicals at Rasappa Chetty
Street, Mirror and Glass products at
Devaraja Mudali Street, Electrical
products at Govindappa Naicken
Street – all have very close
proximity to NSC Bose road and
lined up throughout the stretch of
NSC Bose road, Evening Bazaar,
Rattan Bazaar etc., makes it the
hub of commercial hyperactivity.
● The Chenna Kesava Perumal &
Chenna Malleeswarar Temple,
Kandakottam, Durgah all brings it
a religious destination too.
● Adjacent Landmarks – Rajiv
Gandhi Govt. General Hospital,
State Secretariat, Chennai Port
Trust.
Details of the Road
Corridor I - NSC Bose Road
● Four Lane road divided carriageway
with central median for entire
stretch & Footpaths are provided
with varying width of 1.00 m to
2.00 m for most part of the stretch.
●On-street
authorized
parking
throughout the stretch from
Parrys Corner to Esplanade road
on High Court side and in rest
of the stretches vehicles parked
intermittently unauthorized.
● Pedestrian Zebra Crossings are
provided at designated locations.
However peak movement is
observed near the junctions in
pedestrian crossing than allover
and Speed Breakers have been
20
provided
before
pedestrian
Crossings along the stretch for the
High court stretch alone.
● No exclusive above/below grade
facilities for safe Pedestrian
movement in this stretch except at
Fort Railway station.
● Signals have been provided at
junctions of Parrys Corner and
Esplanade Road with NSC Bose
road and at junction of Esplanade
Road & Sir Muthusamy Iyer Salai.
Corridor – II Rajaji Salai (leading
to Beach Railway Station – towards
North)
● Importance of Carriageway due
to Parrys Corner, Burma Bazaar,
Sub-Magistrate court, State Bank
of India Head Quarters, General
Post Office, Chennai Collectorate,
Beach Railway Station, Custom
House, Harbour etc.,
● Two Lane divided carriageway with
intermittent median through out
the stretch & Footpath is provided
with a varying width of 1.00 m to
2.5 m and 4.5 m at Sub-way. The
western end near Parrys Building
of the Foot path was guarded and
be removed during second season
survey.
● Corridor experiences heavy Traffic
& frequent Traffic Jams
● 3 Pedestrian Crossings available at various points and
a Subway is provided in
front of Beach Railway Station.
● Signals are provided at junctions
of Parrys Corner & NSC Bose road
junction and near Beach Station.
● Footpath at eastern end of
Rajaji Salai is fully encroached
upon by the vendors & so evidently
Pedestrians are forced to use the
Carriageway frequently.
Corridor III - Sir Muthusamy Iyer
Salai
● Four Lane divided carriageway
with centre-median throughout
and Footpath varying from 1.00 m
on the Station side to 4.0 m on the
Opposite side.
● Corridor experiences heavy Traffic
& frequent Traffic Jams
● A Pedestrian Crossing at the signal
and One Foot over Bridge near the
Fort station were provided.
● Signal is provided at the
intersection
of
Esplanade
road and Sir Muthusamy Iyer
Salai.
Present Condition:
NSC Bose Road
● The stretch of Footpath on the
Northern end of NSC Bose road
remains unusable due to the presence
of the Street hawkers & vendors.
The Footpaths are used as dwelling
place by families during night &
early hours of the day. Foot-paths
though available in stretches along
the road are mostly inconspicuous
due to the dominant presence of the
hawkers and encroached upon by
the shop owners
● The
footpaths
are
mostly
inaccessible to the pedestrians due
to the occupation of the edges of the
pavement by the Street Hawkers
and due to the on-street parking.
Surprisingly, a triangular parcel
of land is used exclusively for
parking of two-wheelers near the
Statue of King George – V, which
acts as a Traffic Island next to
the Flower Bazaar Police Station.
● The Footpath on the Broadway Bus
stand side is fully not usable by the
Pedestrians. They are forced to
walk on the carriageway.
Rajaji Salai
● Footpath, 2.5 m wide throughout
on the Beach Station side is
encroached upon by the stores/
vendors.
●On the Western side of the road,
PCO Booths & few vendors have
encroached.
● Unauthorized
parking
seen
throughout except Bus stops &
signal.
Sir Muthusamy Iyer Salai
● Road is filled with vendors on
many stretches of the road on the
Station side.
INDIAN HIGHWAYS, November 2014
TECHNICAL PAPERS
Esplanade road
● Construction of Tunneling for
Metro Rail is in progress in this
stretch of road – Work by CMRL
on one side and the other half of
the road is open for users. Now the
Road is fully open for construction
work.
Rattan Bazaar Road
● Two rows of parallel parking on
the Western side.
Data Collection
Features related to Pedestrian
The existing features or the road
furniture’s related to the Pedestrians
such as Pedestrian facilities, Hazards
to Pedestrians were noted.
Locations for Volume Count
Pedestrian Volume Count
25 locations were selected altogether
viz., 13 locations in NSC Bose road,
3 locations in Esplanade road, 1
location in Frazer Bridge road, 2
locations in Sir Muthusamy Iyer Salai
and 6 locations in Rajaji Salai for
Pedestrian Volume Count Survey.
Vehicular Volume Count
1 location as Mid-block Section
between the Rajaji Salai & Esplanade
road was selected for Vehicular Volume
Count Survey on both sides.
Road Conditions
Mostly fair for most part of the road
except closer to the Flower Bazaar
Signal Time Studies
Signal Timing/Cycle at two of the
signalized Intersections were noted.
in the annexure below:
Comparison between TVC & PVC
at NSC Bose Road
●Vehicular Traffic is at its peak from
9 a.m. to 8 p.m, whereas Pedestrian
Volume count steadily increases
from 7.00 a.m. till 11.00 a.m. and
from 4.00 p.m. till 8.00 p.m. PVC
is at its peak at 5.00 p.m.
From the above data following are
inferred:
● The highest Peak hour Volume is at
Beach Station as 5299 followed by
Bus Terminus as 4106.
● The 24 hr Pedestrian Volume Count
(Total) of a day is the highest at
Bus Terminus amounting to 23441,
the next being opposite to the Bus
Terminus amounting to 17879.
Traffic Signal Cycle & Timing
At Parrys Junction, the meeting point
of NSC Bose road and Rajaji Salai,
is the busiest leg happens to be the
NSC Bose road which has constant
continuous greater signal time of all
Green and all Red and the same has
been taken for analysis.
The average all Green in this leg is
1min. 19.6 sec. and the average all
Red is 1min.20.83 sec.
On
analyzing
this
Signalized
Intersection for this leg, the followings
are observed:
● The total time taken for one cycle
is 3 min 59.89 secs. The signal
timing for all Green and all Red
for this leg is more or less the same
implying a fixed equal time for
both approximately.
● The Green time to cycle ratio is
33.18% and that of Red Time to
cycle ratio is 33.70%.
● The Pedestrian Green for the Rajaji
Salai leg towards Beach is 14.1sec
Accident Data for Pedestrians
12 accidents have occurred in NSC
Bose road from 2008-2012. Similarly,
22 accidents have occurred in Rajaji
Salai during the same period. Accident
data for Pedestrians from 2008-2012
reveals the following.
Problems/Deficiencies noted
● Footpath - not as per required
standards for the Pedestrian
population
● Capacity of roads & Footpath
not fully utilized due to roadside
vendors, dwellings and improper
Pedestrian Crossing
● Heavy Pedestrian flow during most
parts of the day;
● Effective Usage of the Road is
reduced due to –
 Improper Drainage at some
locations during rainy seasons
 Space near Footpath (i.e.)
Shoulders or some part of the
roads are occupied by vendors viz.,
locations near Kuralagam, Flower
Bazaar
● Encroachments near Fort Beach
Station both in Footpath &
Road and also from Broadway
Bus Terminus to Rattan Bazaar.
● CMRL Construction work is
in progress at Esplanade Road
reducing the width of road for usage
by Road users & Pedestrians
●Vehicular Traffic constitutes of
Two wheeler 50%, Autos 25%,
Cars 13% of Total 24 hr Volume
Count.
●Vehicular Traffic is at its peak from
9 a.m. to 8 p.m.
PEAK HOUR & AVERAGE
HOURLY PEDESTRIAN VOLUME
COUNT
The Peak Hour Pedestrian Volume
Count, Average Volume Count for
various locations of the Zone is given
INDIAN HIGHWAYS, November 2014
21
TECHNICAL PAPERS
Suggestions/Remedial Measures
● Pedestrian Volume
count
near
Kuralagam & Bus Terminus is greater
than 4000; hence requires 3.50 m wide
Footpath as per IRC:103-2012 for LOS
C whereas 1.00 m Foot Path alone is
available. Moreover it is a transit area
hence 5m wide footpath will be the
most required one.
● Foot path at many locations within
the study stretch, is not commensurate
with the pedestrian volume
● Footpath of 3.0 m width should be
provided near other Busstops.
● An additional width of 1.00 m needs to
be added for footpaths near shopping
zones. Similarly an additional width
of 0.5 m needs to be added near
buildings.
● A minimum of 3.00 m width should
be provided for Pedestrian crossing
for all the Pedestrian crossings with
a spacing range of 80 m – 150 m,
whereas Pedestrian crossing of 2.0 m
width alone is provided.
●Vendors at Footpath in Rajaji Salai,
Near Kuralagam and Flower Bazaar
needs to be removed.
● Encroachments between Broadway
Bus Terminus and Rattan Bazaar Road
needs to be removed.
● Proper Drainage needs to be provided
at NSC Bose road near the kerbs to
prevent stagnation of water during
rainy season.
● Width of Foot path in Rattan Bazaar
road right turn, right side corner is
very minimum (i.e.) less than 0.75 m
and has to be increased to 2.50 m.
● Based on the Pedestrian & Traffic
Volume Count, a Controlled crossing is
required at the Armenian St. T-junction
of NSC Bose road.
● Based on the Signal Data, a Pedestrian
Foot over Bridge or Foot under Bridge
is required at the Parrys Corner.
● Unauthorized Parking needs to be
removed from NSC Bose road, Rajaji
road, and Rattan Bazaar road.
● Alternate arrangements have to be made
for Utilities such as Electric Junction
Boxes & PCO Booths occupying the
footpath of roads.
● Stop line with studs should be provided
before Pedestrian crossings at Beach
signal, Rajajisalai, and NSC Bose
road.
Conclusion
The data pertaining to the condition of
the facilities provide an insight to the
planner on the extend of the demand. This
if objectively measured and rated through
G.I.S. aided Analysis would help the
decision makers, to identify problem areas
and attend to the same. The solutions can
also be varied from Short, Medium and
Long term, based on the availability of
funds and field situations. The template of
the data collection, analysis of the existing
condition, could be generalised as a model
for any situation, that could predict the
pedestrian’s proneness to accidents.
ANNEXURE
S. No.
Location
Volume Crossing
Total
Volume
Sidewards
Total
Peak Hour
Peak
Hour
Volume
Average
Volume/
Hour
1
NSC Bose Road & Rattan Bazaar road Junction @ Flower Bazaar Police Station
1816
11751
4 PM to 5 PM
3335
1356
2
NSC Bose Road @ Babu Juicel and side
7452
8772
4 PM to 5 PM
2506
1622
3
NSC Bose Road @ Police Booth, Telephone Exchange
4908
2605
7 PM to 8 PM
1331
751
4
NSC Bose Road @ Bus Terminus Opp. side
9795
8084
6 PM to 7 PM
3837
1787
5
NSC Bose Road @ Bus Terminus side
12389
11052
6 PM to 7 PM
4106
2344
6
NSC Bose Road @ Esplanade Road Junction (Kuralagam Entrance Opp. side)
7530
9097
6 PM to 7 PM
3779
1662
7
NSC Bose Road @ Esplanade Road Junction (Kuralagam Entrance side)
3937
8004
7 PM to 8 PM
2689
1194
8
NSC Bose Road @ Esplanade Road Junction (High Court Entrance Opp. side)
1135
10347
6 PM to 7 PM
2286
1148
9
NSC Bose Road @ Esplanade Road Junction (High Court Entrance side)
2524
3198
4 PM to 5 PM
1510
572
10
NSC Bose Road @ Armenian st. (Opposite side)
2330
731
4 PM to 5 PM
2424
1091
11
NSC Bose Road @ Armenian st. (Same side)
2942
7977
5 PM to 6 PM
656
296
12
Parrys Corner Rajaji Salai - NSC Bose Road Junction (Railway Station Side)
790
1312
9 AM to 10 AM
673
299
13
Parrys Corner Rajaji Salai - NSC Bose Road Junction (Opp. Railway Station Side)
2216
775
9 AM to 10 AM
465
210
14
Sir Muthusamy Iyer Salai @ Fort Station FOB Near Petrol Bunk side
9645
1495
10 AM to 11 AM
2081
1237
15
Sir Muthusamy Iyer Salai @ Fort Station FOB Near Burma Bazaar side
5506
330
10 AM to 11 AM
1509
729
16
Esplanade Road @ Raja Annamalai Mandram Opp. side
2351
4084
10 AM to 11 AM
1259
804
17
Sir Muthusamy Iyer Salai @ Tamil Isai College
496
3189
10 AM to 11 AM
927
409
18
Frazel Bridge Road @Raja Annamalai Mandram Back side
10196
2730
10 AM to 11 AM
1976
1436
19
Esplanade Road @ Broadway Bus Terminus Opp. side, near Aavin Booth
832
8056
4 PM to 5 PM
1202
988
20
Rajaji Salai near SBI
8712
960
9 AM to 10 AM
2954
1075
21
Rajaji Salai @ Beach Station subway Towards Beach station
16799
-
6 PM to 7 PM
5299
2100
22
Rajaji Salai @ Beach Station subway Towards Jesus Calls Building
16865
-
9 AM to 10 AM
3483
2108
23
Rajaji Salai @ Beach Signal
3422
1485
10 AM to 11 AM
1439
613
24
Rajaji Salai @ HP Petrol Bunk near Beach Station
3492
3795
6 PM to 7 PM
1899
911
25
Rajaji Salai @ Post Office, Magistrate Court
4044
1506
7 PM to 8 PM
978
694
22
INDIAN HIGHWAYS, November 2014
Ministry of Road Transport & Highways Circular
Circular and Annexure are available on Ministery’s Website (www.morth.nic.in) and same are also available in Ministery’s Library.
INDIAN HIGHWAYS, November 2014
23
Government of Tamil Nadu
HIGHWAYS DEPARTMENT
National Highways Circle, Tirunelveli 627011
TN No.01/2014-15/DO, Dated: 16.10.2014
NATIONAL COMPETITIVE BIDDING
INVITATION FOR BIDS ON ONLINE MODE ONLY
(Two Cover System)
Sl.No.
On behalf of the Governor of Tamilnadu the Superintending Engineer, National Highways,Tirunelveli
invite bids through online only for construction work as detailed in the table.
Name of Work
1
2
3
Bid
Security
Rs. in
Lakhs
4
Cost of tender
document
plus VAT in
Rs.
5
1657.00
Lakhs
30.00
Lakhs
15000+
750
Value of
work Rs.
in lakhs
Annual Plan 2014-2015 Tirunelveli (NH) Division
1 Periodical Renewal in
aggregate length of 20.89km
(Scattered stretches) from
KM 604/0-653/0 of NH 47
(New NH544) from Kerala /
Tamil Nadu Border to
Kanyakumari section in the
state of Tamil Nadu
Concerned
NH
Division
6
Divisional
Engineer (NH)
Tirunelveli
Period of
Completion
in months.
7
10 (Ten)
Months
1. Document available Online in the website https://morth.eproc.in from 18.10.2014 to 20.11.2014 upto
17.00 Hrs.
2. The bidders are requested to pay Rs.1295/- (inclusive of all Taxes) (One Thousand Two Hundred and
Ninety Five only) towards Tender processing fee (non-refundable) shall be paid to M/s. C1 India Pvt. Ltd.
against Tender Processing Fee through E-Payment gateway using Credit Card / Debit Card Master Card
and Visa Card only.
3. Pre bid meeting on 30.10.2014, 11.30 a.m. @ Ofifce of the Superintending Engineer, National Highways,
Tirunelveli.
4. Last Date for submission of Tender Online 21.11.2014 upto 15.00 hrs.
5. Tender Opening 28.11.2014, 15.15 hrs at the office of the Chief Engineer, National Highways, Chepauk,
Chennai-5.
6. The bidders must possess Digital Signature Certificate of Class III (Signing & Encryption) for submission
of bids through online in the above website.
7. For further details & other conditions visit https://morth.eproc.in
8. The Bid security in the form of demand drafts will not be accepted.
DIPR/4450/Tender/2014
24
Superintending Engineer,
National Highways, Tirunelveli
INDIAN HIGHWAYS, November 2014
INDIAN HIGHWAYS, November 2014
25