Question 3 (25 Marks)
An 8.0 m span beam supporting a uniformly distributed load of 5 kN/m and a point load
of 50 kN is shown in Figure 3.
(a). Show that the vertical reactions at the supports 'A' and 'B' are 12.5 kN and
77.5 kN respectively.
(b). Draw to scale, on graph paper, the shear force diagram.
(10%)
(c). Draw to scale, on graph paper, the bending moment diagram.
(25%)
(d). Identify and locate the maximum \"sagging\" and \"hogging\" bending moments.
(25%)
(10%)
(e). Calculate the maximum bending stress if a rectangular hollow section, whose
outer dimensions are 175mm x 150mm with a 5mm wall thickness, orientated so
that it is bending about its major axis of bending is used for the beam.
(30%)
Note: Shear force and bending moment diagrams should be properly labelled with units
(on both axes). Maximum values should be indicated.
