Research Method Of System Reliability For Long-span Rigid Form Bridge

Continuous rigid frame bridges have a widely used in the highway, especially in the western mountainous area where are many valleys, with its superior structure features. At present, the main security analysis method of the structure is deterministic finite element method. However, there are many random factors in practical projects. Reliability based on probability theory is required in analysis of rigid frame bridge. In this paper, the project background is"Ya Lu Expressway Ying Jing section of the La-Ba-Jin Bridge". Its components and system reliability in the construction and operation of the calculation methods had been researched. Specific researches are as follows:(1) The method of basic reliability calculation and the computing on MATLAB software have been described. Calculator of reliability has been developed on the basis of GUI function. The calculator integrates multiple reliability calculation method. This will make foundation of structural reliability analysis for large-scale basis(2) The changed response surface method has been proposed based on the second sequence response surface method. After a numerical example, the algorithm can fit the performance function guarantee the accuracy of the premise, quickly and accurately. The problem that long-span continuous rigid does not exist explicit function is solved.(3) The attentions have been dscribed on the process of bridge system reliability. Failure mode sum methods and system reliability search methods have been described. The largest cantilever bridge construction phase and into the bridge under load combination operations of the performance function of multiple failure is fitted, based on the response surface method. And the main failure mode is analyzed. The span continuous rigid frame bridge does not exist the problem of explicit performance function is solved(4) Sensitivity analysis have been made on parameter distribution of"La-Ba-Jin"bridge. On this basis, can be clearly continuous rigid frame bridge construction process should focus on control of some of the construction parameters to improve the construction quality control in the initiative, to ensure the construction and operation of the design of the bridge were able to achieve a reliable indicator.