Engineering Mechanics Resubmission Assessment Brief

Guidelines for the Assessment Submission

Assessment Brief

Students who have failed the exam component of the assessment must resubmit it in full. The scope of this assessment includes solving 4 questions in relation to engineering mechanics. All questions must be attempted and a mark of 40% for the whole assessment should be achieved.

Your submission must be a single PDF file, containing all the answers to the questions, and a single LinPro model file.

Your working may be hand-written but answers to discursive questions must be typed. Extracts/Screenshots from software can be attached as images, but they do not substitute hand calculations where they are required. Make sure that all numerical results required on the exam paper are in it. Do not attach separate image files to your submission.

You need to ensure that the images are appropriately scaled and rotated. Inappropriately attached images will not be assessed.

Answers not justified by the required calculations or discussion will not receive any marks.

If you need to answer a sub-question which uses values from a previous sub-question, but you were unable to answer the previous one, make logical assumptions, state them clearly in the beginning of the sub-question and solve/answer accordingly.

Each of the four questions is independent from each other.

(a) Where would you expect the maximum (a) bending moment, (b) shear force for the beam in the figure above? Explain why.

(b) Draw the deflection of the beam. Where would you expect the maximum deflection? Explain why.

(c) There are two beams with identical cross-sections. One of them has two fixed ends and the other one has two pinned ends. Both of them have a uniformly distributed load over their full span. Which beam will develop the maximum:

(a)bending moment?

(b)shear force?

(c)chord rotation (slope)?

(d)deflection?

For each of the above, justify your answer appropriately. Answers without justification will receive no marks.

(d) Show the stress distribution of a rectangular hollow section subjected to biaxial bending and shear force. If multiple states are possible, sketch them all and explain how they would be attained.

Q2 (a) A beam with a fixed support on the left end and a pinned support on the right end has a shear force distribution described by the following formula:

(a)The length of the beam.

(b)The deflection of the beam at its mid-span as a function of EI.

(b) Find the minimum required second moment of area of the cross-sectional profile for the beam in sub-question 2a if the section is made of structural steel and the maximum admissible deflection at the mid-span is 25mm. 5%

(c) Design a square hollow section with a uniform thickness of 10mm which will be used for the beam in sub-question 2b.

(d) Design a circular hollow section with a uniform thickness of 10mm which will be used for the beam in sub-question 2b.

(e) A 6m long propped cantilever beam carries a uniformly 30kN/m distributed load over its whole span and a 100kN point load at a distance of 1/3 of its length from its fixed support. Draw the internal forces diagrams for the beam.

Q3 A 15m continuous beam with pinned ends has internal supports at 3m, 8m, and 12m from its left end. Name the supports A, B, C, D, and E from left to right respectively. The beam carries a uniformly distributed load of 5kN/m over span AB, has a 100kN point load at the mid-span of CD. The self-weight of the beam is 10kN/m.

Draw the internal forces diagrams for the beam. Calculate the support reactions.

Q4 (a) The steel truss shown in the figure below is used to support a highway bridge, as shown in the figure below. The deck is constructed as a solid slab with lateral ribs 0.5m high which coincide with the vertical components of the truss. The distance between truss joints in metres is L = 3+0.1N, where N is the last digit of your student number.

Using LinPro, model the bridge as a two-dimensional structure. Assume a slab load of 30kN/m. List all modelling assumptions made and justify appropriately.

(b) Discuss the shortcomings of the modelling approach adopted and/or the software used. Explain how these could be overcome, if possible.

(c) Propose a method to analyse the whole structure without the need for structural analysis software. Explain the different analysis steps and use sketches/diagrams where needed. Would the results yielded be the same as those taken from LinPro? In any case, explain why.

(d) Discuss potential health and safety issues that might occur during construction of this structure. Propose measures to mitigate the risk for each hazard listed.