Study On Detection And Reinforcement Applications Of Beam-arch Association Bridge Based On Load Tests

In recent years, with the development of science and technology, the constructionof bridge in China has made remarkable achievements，Especially such as concretefilled steel tubular(cfst) arch bridge and steel truss arch bridge in our country hasmade a wide range of applications and development. At the same time, however,compared to the domestic research for the detection and evaluation of suchbridge-type with the developed countries,we are still in the primary stage, manytheoretical methods and engineering experience require further evidence andexploration.This paper has summarized the existing bridge inspection and evaluationmethods and theories， taking a88m span concrete filled steel tubular archbridge-Zhaojiagou Bridge for Engineering example according to the latest highwaybridge technical condition assessment standards issued by the Ministry of Transport in2011. This paper has detailed the site detection and evaluation process and theapparent features of some typical special diseases(shear hinge damage, structuralcracks, etc.), At the same time, this paper has done the assessment woke of carryingcapacity for this bridge combined with the finite element method and gotten thetechnical condition rating according to test results based on the latest specification.This paper has also taken a135m span of two-span continuous steel arch bridgefor engineering background and introducted the load test and the process of hangerforce test in detailed. This paper has analyzed the stress and secondary stress on thesteel truss complex node test and the basic principles and the external factors thatimpact hanger force test accuracy. Full-bridge load load test and hanger force testresults has showed that the bridge has a good overall construction quality and met thedesign and normal commissioning requirements.In addition, this paper has also summarized the modal parameter identificationmethod based on environmental incentives to the bridge structure, applied spectrumpeak method and random subspace method two kinds of identification to a singletower cable-stayed bridge with double cable planes modal test.The test results ofmodal parameter identification by the contrast of the finite element analysis resultshas verified the two identification methods are effectivly.This paper has taken the process of load testing and modal testing of several bridges for clues and makes the latest industry standardsand procedures applied to theactual bridge inspection and assessment work, and get some experience, hoping forproviding some reference value to the future similar bridge’s detection and assessmentwork.