Finite Element Reliability Theory And The Study Of Its Applications To Cable-Stayed Bridge

During recent decades cable-stayed bridges are paid more attention in the field of bridge construction, and about 300 cable-stayed bridges have been built in the world. Because there are many uncertain factors during construction and management period of cable-stayed bridges, estimate reliability of cable-stayed bridges on the basis of considering stochastic of materials, geometrical size, load and so on to simulate the uncertainties of structures.This thesis firstly studies the theory of structure reliability, summarizes the various computational methods, and compares them with each other. Then reliability method based on stochastic finite element method is discussed detaildely, and program frame on this method is given. At last, computional reliability and sensitivity of cable-stayed bridges under serviceability limit states with the method of Finite Element Reliability Method (FERM) is given tope priority to be discussed. Take SiFangTai cable-stayed bridge of Harbin as an example, adopting simplified computational model, which is matched with the actual situation possibly. Building limiting equation according to the maximal vertical displacement of the girders under vehicle load without regard to impact. FERM is utilized to compute system reliability of cable-stayed bridge under serviceability limit states, the result shows the bridge is reliable. Finally, the most influential random variables on the reliability of cable-stayed bridges are cables'area by using sensitivity analysis, and the influence of cables'area declines with the increase of loads.