Evaluation And Study On Reliability Of The Structure Components Of A Bridge With Consideration Of Time-dependent Resistance

Bowstring arch bridge is a bridge form in our country . And they are the keys to transportation safety. However, there are a large number Of Existing Bowstring arch bridges which have been deteriorated, Damaged and incapable of load-bearing. It has become a worldwide Problem. How to assess these bridges scientifically and reasonably Also become a subject that is followed with great interest at home And abroad. Studying the reliability of Bowstring arch bridge possess not only important theoretical meaning, but also widespread prospect for engineering application and great economic and social benefit. When analying the reliability of the existing Bowstring arch bridge structure , the resistance dependent on time is considered in this article .In view of this reason , a new attenuation modling for the existing structure have been set up .On this basis ,the analysis and calculation method on reliability of the existing structure with consideration of Time-dependent resistance is put forward .in the end ,the theory of reliability is applied to carrying capacity assessment. When calculating the reliability ,the scientific workers have improved forcal point for first order second movement method advanced by others and use JC method that is improved forcal point for first order second movement method or called checking point method ,which is very applicable to reliability study ,if there are non-normal distribution variables in real engineering. The specific method will be introduced: first of all, find reasonal checking points ,then on the limit state surface ,make a tangent plane through checking points, thus ,the distance between the origin and the tagent plane is reliability index which scientists want to get. When the resistance have been calculated ,steels and concrete material are considered as the function, so that every moment of the corresponding resistance will be obtained easily . Bowstring arch bridge is a structure form. In considering the reliability of components at the same time ,scientists also discuss the structural reliability ,integrated assessment of Indicators for structural system is to weight and sum part assessment of indicators ,at last calculate structural target reliability ,through which scientists predict the Bowstring arch bridges'service life-span in order to offer material for maintenance and reinforcement.