13.8 Moving-load systems create varying patterns of moment and shear within beams. The absolute maximum moment and the absolute maximum shear are created when the load system is at specific positions on the beam. PROBLEMS Section 13.3 Beam Reactions 13.1 through 13.6 Calculate the reactions at points A and B for the beams shown. 10 k 10 k B 30 kips 3'-0" 2'-0" 1.2 kips/ft 5'-0" (b) 4'-0" B