Load moves along the three-hinged,  parabolic arch ABC, shown in Figure P12.24.  Construct the influence lines for the reactions at  C, and shear, axial load and moment at point D.  The equation for the parabolic arch is y = 4hx2 /L2 . If a point load P = 3 kips is applied at B,  compute shear load at D.<image 1>
['-1.84k compr', '-1.94k compr', '-1.74k compr']