PASS MOCK MIDTERM 1 – FOR PRACTICE ONLY Course: CIVE 3202 A (Winter 2015) Facilitator: Veronica Santos Dates and locations of mock-midterm take-up: Feb.2nd (SA 402) and Feb.4th (SA 402) IMPORTANT: It is most beneficial to you to write this mock midterm UNDER EXAM CONDITIONS. This means: • Complete the midterm in 80 min (s). • Work on your own. • Keep your notes and textbook closed. • Attempt every question. After the time limit, go back over your work with a different colour or on a separate piece of paper and try to do the questions you are unsure of. Record your ideas in the margins to remind yourself of what you were thinking when you take it up at PASS. The purpose of this mock exam is to give you practice answering questions in a timed setting and to help you to gauge which aspects of the course content you know well and which are in need of further development and review. Use this mock exam as a learning tool in preparing for the actual exam. Please note:  Come to the PASS session with your mock exam complete. There, you can work with other students to review your work.  Often, there is not enough time to review the entire exam in the PASS session. Decide which questions you most want to review – the Facilitator may ask students to vote on which questions they want to discuss.  Facilitators do not bring copies of the mock exam to the session. Please print out and complete the exam before you attend.  Facilitators do not produce or distribute an answer key for mock exams. Facilitators help students to work together to compare and assess the answers they have. If you are not able to attend the PASS session, you can work alone or with others in the class. Good Luck writing the Mock Midterm!! DISCLAIMER: PASS handouts are designed as a study aid only for use in PASS workshops. Handouts may contain errors, intentional or otherwise. It is up to the student to verify the information contained within. PLEASE NOTE: THIS HANDOUT IS NOT TO BE DISTRIBUTED. PART A – Multiple Choice Questions Answer all 5 multiple choice questions below. Clearly circle your answer. [2 marks each] 1) When is a beam subjected to unsymmetric bending? A) When the resultant internal moment acts along the neutral axis B) When the cross-section is unsymmetric about an axis perpendicular to the neutral axis C) When the cross-section is unsymmetric about the neutral axis D) When the resultant internal moment does not act along the neutral axis E) B and/or D 2) In order to analyse the stresses of a composite beam the transformed section method is used to transform the beam into a single material. Why is the width of a material increased or decreased during this transformation instead of its depth? A) Because there is a linear increase in moment of inertia (I) in composite beams and an equivalent moment of inertia must be found. B) Because the moment of inertia (I) of a composite beam is only dependent on the depth of the stiffer material. C) Because by transforming the depth of a composite beam it will cause the stresses to vary nonlinearly. D) If the width is transformed, the depth must also be transformed. E) B and C 3) Which sentence best describes the stress distribution of a composite beam? A) The stress distribution is different between the different materials due to the sudden change in stiffness between materials. B) The stresses and strains are the same at the juncture of the two materials. C) The stress distribution of a composite beam is non-linear due to the sudden change in strain between materials. D) The stress distribution of the transformed beam is 2/3 of the stress distribution of the original section. E) There are no stresses induced in a composite beam since the stresses from each material cancel each other out. 4) What is true about the shear flow distribution in thin-walled members? A) q varies parabolically along segments that are perpendicular to the shear force V and linearly along segments that are parallel or inclined to the shear force V. B) q varies parabolically along segments that are parallel or inclined to the shear force V and linearly along segments that are perpendicular to the shear force V. C) q has a linear distribution along the flange and web of the cross-section. D) q has a parabolic distribution along the flange and web of the cross-section. E) q has a constant distribution along all segments of the cross-section. 5) The main difference (s) between straight beams and curved beams is A) The stress distribution of curved beams vary hyperbolically. B) It is easier to bend curved beams, therefore the stresses are lower in curved beams compared to straight beams. C) The neutral axis of a curved beam shifts away from the centroid towards the centre of curvature while the neutral axis of a straight beam does not shift away from the centroid. D) The stress distribution of straight beams vary linearly while the stress distribution of curved beams is constant along the cross-section. E) A and C PART B – Long Answer Questions 1) Find the location (e) of the shear centre (O) of the cross-section shown below. The flanges have a thickness of t and the web has a thickness of 2t. What is the meaning of the shear centre? Draw a diagram to illustrate your explanation. [20 marks] 700 mm 600 mm O e 500 mm 200 mm 2) Consider the T-beam cross-section below. If the resultant internal moment is 85 kN m, find the following: [20 marks] a. The bending stress at points A and B b. The angle of the axis at which the bending stress is zero (σ = 0) c. The percent increase or decrease in the bending stress at point A if ϴ = 0o 600 mm A 40 mm 500 mm 50 mm B BONUS [1 mark] Draw the shear flow and the shear flow distribution of the thin-walled member below. V