Influence of constructing transverse concrete diaphragms in different distances on the dynamic and static behavior of prestressed concrete T-beam bridge structure

Structure of diaphragm was defined as a transverse strengthener beam which located between beams or girders to keep section geometry. It plays significant role provide the stability bridge and distribute vertical axial loads. The main objective this study investigate influence construction concrete diaphragms T-beams at different distances on dynamic static behavior T-beam structure. methodology research includes five case studies. first had no diaphragms, second supports (abutment piers), third center each span bridge, fourth 1/4 fifth 3 m bridge. Three analysis methods were used determine responses by using finite element method in CSI-Bridge ver. 20. These included modal analysis, time history spectra analysis. Dynamic consisted unloaded frequency, loaded displacement. Static done find such bending moment deflection. results shown that has not important effect improvement frequency (natural frequency) horizontal directions, but they an reducing (vibration direction For state, causes increase downward deflection because these cross lead dead load (self-weight structure), resulting increasing due service loads (dead load, prestressed trucks load). Therefore, there is need resist over diaphragms.