Study On Mechanical Characteristics And Model Simplification Of Simply Supported Bridge With Multiple T-Beams

First, the effects of transverse connections and diaphragm parameters (quantity, location and thickness) on mechanical characteristics of simply supported bridges with multiple T-beams are analyzed. Based on an engineering project, a finite element model is established and the lateral distribution factors of live load with different transverse connections are calculated. Comparing the numerical results with the simplified algorithm, this thesis presents a simplified calculation method of the lateral distribution factor of live load of simply supported bridges with multiple T-beams with different transverse connections. Fi(?)lly, the finite element model of a double-tablets single track railway simply supported T-beam bridge is established and the relation between its inertia equivalent moment and that of a single T-shaped beam is analyzed. Research on the simplification of the finite element model is done. The main contents of the thesis are as follows:1) According to the structural characteristics of the simply supported bridges with multiple T-beams, three finite element solid models are established by ANSYS, which considers different transverse connection condition (hinge joint, semi-rigid connection and rigid connection). Based on these finite element models, the deformation is calculated and the effects of the transverse connections and diaphragm parameters on the mechanical characteristics are analyzed.2) The common simplified algorithms of the lateral distribution factor of live load of simply supported bridge with multiple T-beams are introduced. Combined with example, the numerical analysis of the lateral distribution factors of live load by using the finite element model is carried out. Compared with the results using simplified algorithm, research on the reliability and applicability of the simplified algorithm of the lateral distribution factors of live load is conducted and a simplified algorithm for different transverse connections is presented.3) The full finite element model and simplified model of a double-tablets single track railway simply supported T-beam bridge are both established by ANSYS. According to the relationship between the deformation and stiffness, the relation between the equivalent inertia moment of the whole beam section and that of the single T-shaped beam section is analyzed. The factors of the effects on equivalent inertia moment are also analyzed using the finite element method.