Theoretical Research Of Non-probabilistic Response Surface Limit Method And Its Application In Bridge Reliability Evaluation

As an important component of traffic routes,bridges play a significant role in transportation.Therefore,it is of importance to evaluate the reliability of the bridge.Traditional probabilistic reliability assessment methods require large sample space.It has many limitations in practical engineering.Based on this,the research object for this paper is the non-probabilistic reliability response surface method based on the interval model.The non-probabilistic response surface limit method is proposed.The main works for the thesis are as follows:(1)Based on the analysis of several conventional non-probabilistic response surface methods,the traditional non-probabilistic response surface method is optimized and the non-probabilistic response surface limit method is proposed.The non-probabilistic response surface limit method is feasible illustrated by numerical examples.The analysis results show that the non-probabilistic response surface limit method can effectively reduce the workload of calculation under the condition of guaranteeing the accuracy,and can eliminate the oscillation and lengthy of the iterative process.The application of non-probabilistic response surface limit method flollows five steps:(1)transform initial parameter into interval value;(2)obtain performance function values using the finite element software;(3)establish response surface equation;(4)solve non-probabilistic reliability index using limit method;(5)evaluate structural reliability based on the obtained non-probabilistic reliability indexes.(2)Based on the non-probabilistic reliability,the bridge reliability assessment process was established.The reliability of three span PC rigid frame bridge for ultimate limit state and serviceability limit state was evaluated using the non-probabilistic reliability limit method.The reliability of the bridge can be judged according to the non-probabilistic reliability index obtained.It is proved that the non-probabilistic response surface limit method is feasiblein practical application.This paper proposed the non-probabilistic response surface limit method and introduced it into the reliability evaluation of the actual bridge.In theory,it hasbroken through the limitation of the traditional non-probabilistic response surface method.In practice,it has provided a new approach for the reliability evaluation of bridges.