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AE – Sample 1 -‐-‐ 1 NOTE: Sample papers have been reformatted with 11 pt. text and 1.5 paragraph spacing to save paper. Advocacy Essay, Sample 1: Safety as the Number One Priority for the San Francisco Bay Bridge
San Francisco-Oakland residents, who drive on the San Francisco-Oakland Bay Bridge every day,
deserve a structure that can be trusted to withstand a large earthquake. In 1989, the 6.9 magnitude Loma
Prieta Earthquake caused a 50-foot portion of the San Francisco-Oakland Bay Bridge’s upper Eastern
span deck to collapse on the bottom deck, killing one life. Despite the fact that not many were injured, the
disaster exposed the Bay Bridge’s vulnerability against high magnitude earthquakes, and more
importantly, the California Department of Transportation’s (Caltrans) weakness in maintaining the
bridge’s safety. Since then, the 280,000 San Francisco commuters that travel the bridge daily have
questioned Caltrans’ motives. In 2003, the California Department of Transportation assessed the San
Francisco area to have a 27 percent chance of having a 6.7 or greater magnitude earthquake in the next 30
years, and if the East Span was not yet completed, then pieces of the existing bridge would collapse
(Penzien). In 2004, Caltrans completed reinforcement on the bridge’s Western span with 50,000 bolted
rivets and 17 million pounds of steel and it has not experienced issues since (Schneider). Unfortunately,
the bridge’s Eastern span has not been as secure. In 1998, Caltrans concluded that building a replacement
bridge for the Eastern span would be more cost efficient than retrofitting the existing bridge, and work
began to construct “the world’s longest self-anchored suspension bridge” (“Much Delayed Bay Bridge”).
In comparison to other traditional suspension bridges that use two or more towers with cables anchored to
the ground, the self-anchored suspension bridge (SAS) contains only one tower connected to cables
anchored to the bridge’s roadway; this SAS design is the first of its kind in the world (Yee and Mina).
Despite the SAS having an aesthetically pleasing façade, many disapprove of its interior organization.
Numerous credible engineers have criticized the SAS design since its proposal, but Abolhassan
Astaneh-Asl’s “Solutions to the Problems of the East Spans of the Bay Bridge” takes a step ahead and
pinpoints the various issues that the SAS will have against another large earthquake. Astaneh is a
Professor of Structural Engineering at the University of California, Berkeley and has studied the Bay
Bridge since the 1989 Loma Prieta Earthquake.
In his solution he addresses his three main concerns with Caltrans’ SAS bridge: the suspension
cables on the bridge are connected to the roadway deck instead of being anchored to the ground like other
successful bridges, the hinges are poorly placed that could cause the bridge to move in different directions
AE – Sample 1 -‐-‐ 2 during an earthquake, and that a large compression force could cause the bridge’s deck to easily collapse
in the event of a small explosion (Astaneh). He then focuses on his solutions: to have the bridge use two
separate suspension cables instead of one that are anchored by Yerba Buena Island and heavy anchor
rocks, placing the hinges of the bridge on the top piers of each side to separate the bridge and its adjacent
spans, and decreasing the axial load of the deck to keep the bridge weightless against great forces.
Although his propositions may appear outdated because the Bay Bridge’s Eastern span is already in the
process of being rebuilt, Astaneh’s solution is still vital to the bridge’s construction since he has centered
his studies on the Bay Bridge’s composition and on the factors that make a suspension bridge safe against
large-magnitude earthquakes for 22 years; unlike other solutions, Astaneh advocates for Caltrans to create
a seismically secure Bay Bridge over the landmark-driven SAS design to protect the lives of San
Francisco commuters should a high magnitude earthquake hit the Bay Area again.
Astaneh’s “Solution to the Problems of the East Spans of the Bay Bridge” was proposed on
January 31, 2005 shortly after Caltrans publicized its model to replace the East Span’s truss-cantilever
bridge with a self-anchored suspension bridge. Astaneh begins his proposal by pointing out the issues
with the SAS bridge that was chosen by the Bay Bridge Design Task Force of the Metropolitan
Transportation Commission in 1998. His first problem argues the danger of having one continuous cable
being anchored to the bridge’s deck instead of to the ground, like other successful bridges, such as the
Golden Gate Bridge, the Bay Bridge’s West Span, and the Al Zampa Bridge (Astaneh). In the event of an
earthquake, the cable’s connection to the deck causes a large axial force on the roadway, causing the
cable to lift the deck and collapse into the bay. Secondly, Astaneh addresses the SAS bridge’s hinge midspan placement between the East span and its surrounding Skyway and Yerba Buena Island (YBI)
Transition Structure. Each of these three structures will have different vibration patterns during an
earthquake, causing each to move in a different direction; these hinges will unfasten and cause the cables
holding the bridge to fall and the entire SAS bridge to come detached from the Skyway and YBI.
Astaneh continues his evaluation by arguing his improvements to make the bridge more
seismically secure, while still maintaining the same artistic and architectural image of the SAS bridge. His
solution to his first main concern is to replace the one cable that is connected to the roadway with two
separate cables that are anchored to Yerba Buena Island and other heavy concrete blocks. This
replacement relieves the bridge’s roadway of a large axial compression and simultaneously reduces the
amount of steel needed in the deck to anchor the cable, and saving a sizeable amount of money for
materials. For his second concern, he suggests placing the hinges on top of the roadway’s pier to divide
the bridge from only one adjacent side instead of the two sides designed in the SAS. This way, the two
sections would not move in separate directions, making the possibility of damage to the main span nearly
AE – Sample 1 -‐-‐ 3 impossible. Ultimately, Astaneh’s solution is the best proposition for the Bay Bridge’s Eastern span
because it requires little addition to the SAS design that is already in construction. If Caltrans’s SAS
model fails once again due to one of Astaneh’s predicted mistakes, Caltrans will have wasted billions of
dollars and labor hours spent on creating a faulty bridge. The SAS bridge has still not been completed, 23
years after its proposal, and including Astaneh’s solutions would not necessitate much extra time or
effort. It is essential that these years of work are not put to garbage.
After the 1989 Loma Prieta Earthquake, Caltrans initially looked to Abolhassan Astaneh-Asl to
provide ideas on the redesign of the Bay Bridge, but Caltrans eventually turned against Astaneh after he
criticized the poor design of the SAS. When Caltrans began gathering notable engineers to develop
designs and ideas for the replacement of the Bay Bridge, Astaneh was one of the first to be invited
because of his professional membership in engineering societies and other significant research projects,
such as the World Trade Center Structural Studies and the I-35W Bridge Collapse. However, when
Astaneh widely publicized his concerns about the SAS Bridge’s lack of seismic safety, Caltrans began
dismissing his views and involvement the bridge’s design. Ron Russell of SFWeekly.com, who once
interviewed Astaneh, found that Caltrans Chief Deputy Director Dan McElhinney stated, “we appreciate
what Professor Astaneh has to say, but we don’t share the same level of concern about seismic
vulnerability; a good many engineers and others have looked at the design and have determined that the
bridge will be safe” (A Bridge Too Weak?). Caltrans publically announced that their SAS bridge does not
prioritize safety against earthquakes as highly as Astaneh’s solution does. On the outside, Caltrans
appears to simply dismiss Astaneh’s studies and advocate their own SAS design, but Astaneh has claimed
that Caltrans even reduced funding to the University of California, Berkeley because of his criticism
(Russell). In February of 2005, once construction of the SAS bridge had already began, Senator Tom
Torlakson requested Astaneh to submit his researched studies on the Bay Bridge; Astaneh replied,
assertively asking that Caltrans treats him with more respect than they have in the past and that he would
not:
be subjected to the treatment that [he] has been receiving since 1998 when [he] exercised [his]
first amendment rights and fulfilled [his] civic duties and professional responsibilities by
expressing [his] opinion in a letter to proper public hearing on a subject that [he has] been
studying for more than nine years (Astaneh 2).
Despite the fact that Caltrans denounces Astaneh’s opinions and asserts that the SAS bridge is seismically
secure enough to withstand an earthquake, Astaneh continues diligently executing his opinions on the
bridge. Caltrans’ motives are supported by the thought that money and popularity will accompany a
AE – Sample 1 -‐-‐ 4 popular Bay Bridge, but they fail to realize that the Bay Bridge could collapse again in another
earthquake, causing Caltrans to backtrack and waste the time and money used in creating the SAS bridge.
Although numerous engineers supervise the SAS bridge project, these engineers place attracting
tourists into San Francisco as a top priority in rebuilding the Bay Bridge. According to Andrew Gumbel
of The Independent World News, The Bay Bridge Design Task Force that was in charge of designing the
SAS Bridge only included one architect out of its seven members, the other six were politicians
advocating for aestheticism over safety; also, only seven out of thirty members of the engineering
advisory panel were involved in studies of bridges (San Francisco’s $5bn bridge to nowhere). Therefore,
less than one fourth of the Design Task Force was actual credible sources in bridge engineering. The other
three fourths of the committee consisted of politicians whose main objectives were to build a bridge based
on landmark appearance rather than seismic safety.
Several credible engineers and urban planners endorse Astaneh’s criticisms of the SAS bridge
design and plainly wish for Caltrans to build the East Spans Bay Bridge with efficiency placed over
imagery. Matthew Dresden, one particular student at the University of California, Los Angeles who is
completing work towards his Masters of Arts (MA) in Urban Planning and the Juris Doctor (JD) in Law,
published an article in 2006 addressing the role of aesthetics in designing and funding huge bridge
projects, such as the Golden Gate Bridge and the San Francisco-Oakland Bay Bridge. In his article, he
states that the Golden Gate Bridge is one of the most famous bridges in the world today and even has its
own gift shop that makes nearly $3 million per year (Dresden 12). He goes on to discuss that The Golden
Gate Bridge was built purely for economic purposes of making travel between the San Francisco
Peninsula and Marin County more convenient without the use of ferries, to outrun Los Angeles in civic
competition, and to accommodate the rise of the car industry; also, when the bridge’s finances were being
discussed in 1930, “not one word addressed the design or appearance of the bridge” (Dresden 13). The
Golden Gate Bridge was not intentionally built to become the iconic landmark of San Francisco, but
rather, was built only to adapt to the growing and modernizing city. On the other hand, The Bay Bridge
was an immensely expensive project built as a cultural phenomenon during its time, overcoming the San
Francisco Bay’s vast aquatic length and depth. Still, its grace never compared to the beauty of the Golden
Gate Bridge. For that reason, engineers should not base the SAS bridge project on how much attention it
will draw from tourists, but should focus on the security of San Francisco residents who must cross the
bridge every day. The Golden Gate Bridge is extremely successful not only because it is a landmark icon
in San Francisco, but rather because its structure has withstood high magnitude earthquakes and other
natural disasters since its construction in 1936.
AE – Sample 1 -‐-‐ 5 After waiting 22 years for Caltrans to complete the new East Span of the San Francisco-Oakland
Bay Bridge, San Francisco drivers deserve a bridge that will not collapse in a high-magnitude earthquake.
The Loma Prieta Earthquake already exposed Caltrans’ failure at maintaining a seismically secure Bay
Bridge, and the new self-anchored suspension bridge has the potential to break down once again due to its
poor design engineering. Abolhassan Astaneh-Asl’s address of these problems in his “Solution to the
Problems of the East Spans of the Bay Bridge” pinpoints the areas that Caltrans has neglected to draw
attention to. Firstly, since the structure is essentially anchored to itself, slight movement in the bridge’s
cables could trigger the entire structure to collapse into the bay. Secondly, in the event of an earthquake,
the design’s faulty hinge placement causes the road’s deckway to sway with three different motions.
Astaneh proposes his solutions to these issues with seismic safety as his number one priority, making his
intentions the best and most protective of San Francisco commuters. Abolhassan Astaneh-Asl has no
intention of swaying tourists to travel to San Francisco and nothing to gain from his promotion of
building of safer bridge, verifying his credibility against Caltrans. On the other hand, Caltrans is
motivated by money, popularity, and notability in creating the new East Spans of the Bay Bridge.
Therefore, Astaneh’s solution promotes the safety of San Francisco residents above all other motives.
AE – Sample 1 -‐-‐ 6 Works Cited
Dresden, Matthew. "Must a Bridge Be Beautiful Too?." Access Magazine 2006: 10-17. Web. 28
February 2011. .
Astaneh-Asl, Abolhassan. A. Astaneh to Senator Tom Torlakson. Web. Berkeley, CA: 17 February 2005.
05 March 2011.
Astaneh-Asl, Abolhassan. Astaneh's Solution to the Problems of the East Spans of the Bay
Bridge.
31 January 2005. Web. 31 January 2011.
Gumbel, Andrew. "San Francisco's $5bn bridge to nowhere." Online Posting. 31 August 2004.
Independent World News. 02 March
The
2011.
"Much-delayed Bay Bridge retrofit feels growing pains." Online Posting. 14 February 2010. The SF
Examiner. Web. 11 February 2011.
Penzien, Joseph, et al. The Race to Seismic Safety: Protecting California's Transportation System. Web.
California Department of Transportation, December 2003. Web. 11
February 2011.
Russell, Ron. "A Bridge Too Weak?." Online Posting. 17 March 2004. SF Weekly. 17
January 2011.
Web.
Schneider, David. "The Bay Bridge: Competing Against Time." Online Posting. 25 April 2010.CBS
News.com. Web. 20 February 2011.
Yee, Elizabeth and Mina, Frank. "A Bridge for the 21st Century." Online Posting. 11 May 1998.
SFGate: Home of the San Francisco Chronicle. 02 March 2011. Web.