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a) Many people answered that load smearing simplified the calculation process, and was an acceptable approximation; that answer received four of the possible five points. A more specific answer is that load smearing puts the load in the same form as other loads (e.g. pounds per square foot) and so makes the loads much easier to combine.
b) The key points are that "elastic" means the material returns to its original shape. "Non-linear" means that the stresses are not proportional to strains.
c) The basic answer is straightforward:
Since the problem describes properties of a structure, rather than a material, the discussion should be in terms of loads and deformation, rather than stresses and strains, although grading on this point was not strict.
Remember that the material scale and structural scale are distinct: a very weak structure may carry high stresses, and a low stiffness structure may be made from a high stiffness material.
d) A variety of answers were accepted for this. The overhang condition was the most common answer.
The following answer correctly identifies the overhang condition, but gives an incorrect explanation.
