Question:
Simply supported PSC bridge gives improper result for bending moment and stress for Moving Load.
Answer:
Dear sir,
The model was unstable and there were abnormal deformations as it could be noted from the analysis message window. Hence, it won't be right to extract results from this model. Kindly restrain all components except Ry at the location of Pin support for structural stability about longitudinal direction and then check the results. Unsymmetric loading about global X axis (like moving load) will cause Mx moment, which wasn't being restrained before and hence the inappropriate results. For a simply supported span, kindly restrain Rx and Rz at the pin support location.