A simply supported composite beam 3 m long carries a uniformly distributed load of intensity q = 3.0 kN/m (see figure). The beam is constructed of a wood member,100 mm wide by 150 mm deep, reinforced on its lower side by a steel plate 8 mm thick and 100 mm wide. Find the maximum bending stresses o, and a, in the wood and steel, respectively, đue to the uniform load if the moduli of elasticity are E. = 10 GPa for the wood and E, = 210 GPa for the steel. q- 3.0 kN/m mm

A cantilever beam AB, loaded by a uniform load and a concentrated load (see figure), is constructed of a channel section. 250 lb 22.5 lb/ft A 5.0 ft 3.0 ft- 0.617 in. 2.269 in. (a) Find the maximum tensile stress o, (in psi) and maximum compressive stress o, (in psi) if the cross section has the dimensions indicated and the moment of inertia about the z-axis (the neutral axis) is I = 3.10 in4. Note: The uniform load represents the weight of the beam. (Use the deformation sign convention.) O, = psi psi (b) Find the maximum value of the concentrated load (in Ib) if the maximum tensile stress cannot exceed 4 ksi and the maximum compressive stress is limited to 18.0 ksi. (Enter the magnitude.) Ib (c) How far from A (in ft) can load P = 250 lb be positioned if the maximum tensile stress cannot exceed 4 ksi and the maximum compressive stress is limited to 18.0 ksi? ft

Q3) A circular bar of 25mm diameter is formed into a semicircular arch and loaded as shown in the figure. Determine the maximum bending stress. Assume that the flexure formula for straight beams is applicable. 200KN 100KN R=1.5m 230°

A railroad tie (or sleeper) is subjected to two rail loads, each of magnitude P = 177 kN, acting as shown in the figure. L 9 £a The reaction q of the ballast is assumed to be uniformly distributed over the length of the tie, which has cross-sectional dimensions b 300 mm and h = 250 mm. Calculate the maximum bending stress o (in MPa) in the tie due to the loads P, assuming the distance L = 1,500 mm and the overhang length a = 495 mm. (Enter the magnitude.) max MPa