Safety Assessment Of Bridge Structure Based On NDT And Static Load Test

As the throat of transportation,bridge engineering has become the key to ensure the smooth access of the national economic artery.However,in the existing bridges,the safety of bridges can not be guaranteed because of the influence of human or environmental factors.The bridge reliability is reduced,the structure function degenerates,and the safety of the bridge structure will be seriously affected.Therefore,the safety assessment of the bridge is critical.This article takes a viaduct in Hunan as a worker.Based on the background,a bridge safety assessment based on NDT and static load test is carried out.First,the concrete defect parts of the bridge appearance inspection are nondestructive testing,and the bridge structure safety is preliminarily identified by nondestructive testing.Then the finite element model of the bridge is established according to the related data of a viaduct in Hunan,which is combined with the numerical simulation of the viaduct and the field load test.Methods to evaluate the safety of the bridge.It provides scientific data for bridge completion and acceptance,safety operation and maintenance.The main work of this article is as follows:(1)Ultrasonic method and ground penetrating radar are used to do nondestructive testing of bridge web in a viaduct in Hunan,and the ultrasonic method is used to analyze the cracks before and after the static load of the bridge.In the process of ultrasonic defect detection,we use different methods to identify outliers.The local safety of bridges is preliminarily analyzed through nondestructive testing.(2)The theoretical analysis of the viaduct and the numerical simulation of the finite element software are carried out.The loading conditions,the main control section and the space position of each test point in the main control section and the section of the cross section as well as the loading and unloading process and the magnitude of the loading and unloading of the bridge site static load test are determined.(3)Through the static load test,the stress,deflection or displacement of the main control section of the Viaduct under the load of various working conditions is measured,and the measured values of each working condition are compared with the simulated values to determine whether the viaduct meets the requirements of the design and the standard.(4)The test results of static load,nondestructive testing and crack observation are synthetically analyzed to evaluate the safety of the viaduct structure,and provide scientific data for the completion acceptance of the bridge and the future maintenance and maintenance work.