Your team has been asked to design a steel beam bridge with an 8m length as a simply supported beam (e.g. Figure 1, which is located in Wollongong). The beam weight is 5kN, considered as a distributed load over the beam length. In addition, in the worst case, two bushwalkers with a weight of 850N each will be on the bridge. They can pass the bridge together or individually. You only need to take the self-weight and pedestrian load into account in your calculations. Hint: you can consider two loads on the beam for each person or one load including the weight of both people.
(a) Determine the scenario that will create the maximum shear force and bending moment on each of the simply supported beam.
(b) Draw the shear force diagram and bending moment diagram based on the loading condition.
(c) Determine the size of the steel I-beam with specifications shown below, with the smallest possible section that can carry the bending moment in the simply supported beam. The maximum allowable stress is 5kPa.