The Detection And Assessment Of Dayifangdu Bridge

With the rapid development of the society and economy,the traffic construction is becoming more and more important,in which the bridge plays a vital role. Because of the overloading of vehicles or the natural disaster or the staving by humen,lots of existing bridges could not been satisfied with the new requirement of the load-bearing capacity. Once the load-carrying capacity of bridge is down,it will seriously threaten humen's life and property. Therefore target-oriented carries on the detection and assessment of existing bridge, can gain the bridge condition promptly.evaluates its actual load-bearing capacity and implement the further processing measure as well, guaranteed that the operation safety and the smooth of the traffic,in addition may accumulate the correlation tachnique material to supplies the similar work to apply and to study.Based on the current situation of domestic and abroad bridges as starting point, this thesis expounds the importance of the detection and assessment on bridge, thus summarizes the method of them. The strength and crack detection of concrete are important contents, and the bridge loading test is basically becoming the essential content as a added one to the general detection, which through the static loading test and dynamic loading test to get the check coefficient and impact coefficients and so on, further to comfirm the actual operational state of bridges. For the assessment part, it introduces the mathods which based on the exterior detection,the code for design of bridge, the reliability theory and the AHP emphatically.This thesis shows the detection and assessment of Fangdu bridge, the main conclusions are as follows:There are many damage defects of the bridge,which will become the danger of the normal use of bridge.These damage defects includes the serious developing crack of slight bending slabs, the slight bending slabs both sides of the carriageway are seriously damaged and bridge joint is failure, the baluster of the bridge crazed and partial breaked and revealed reinforcement. Then used the AHP to assess,and the result is poor.At last, it used the mathod of finite element calculation to assess the load-bearing capacity of the bridge, which included the depravation coefficient of load-bearing capacity and the section discount coefficient,and shows that the bridge can bear the original design load grade of the vehicle-load-20 and the trailer-load-100.But the bridge can not bear the load grade of the highway-load-I...