The Development Of Intelligent Evaluation System About Bridge Health Condition Based On AHP

When modern suspension bridge first been built, it already has a large span, theability to cross is one of its advantages. With the continuously improve of bridgeconstruction standard, the span of bridge has increased, the structure form of bridge alsobecome more and more complex, it is necessary to build bridge health monitoring. Inaddition, the research and its application of bridge health condition becomes a hot andimportant field in civil engineering with the growing attention to the safety, durabilityand the use function of long span bridges.Qingcaobei Yangtze River Bridge locates between Fuling Lidu and NanchuanDouble estuary of Chongqing3rd ring expressway, the traffic flow of this section isvery heavy, the bridge has a large burden, therefore, with the cumulative of time, thestrength and stiffness of bridge will reduce, this will influence safe driving, also it willshorten the lifespan of bridge. Therefore, the assessment of Qingcaobei Yangtze RiverBridge’s heath condition can play an active role in increasing the life span of bridge.This article use Qingcaobei Yangtze River Bridge as engineering background,build evaluation system with the measured data of sensor, thus improve a technical stateassessment software for this bridge. The main contents are followed:First, use the finite element software Midas civil2010to build the model of wholebridge, analysis the static state of bridge structure, define four types of loadingcombination, inquiry the stress and displacement of main girder,main tower,main cableand boom under the influence of loading combination. Calculate out the threshold ofstress, displacement and cable force;Secondly, draw up an implementation plan of bridge health monitoring system,define the key parts which need to arrange sensor, start the real-time online monitoring,and return the measured data,then analyse and add up the measured data；Thirdly, divide the strata of evaluation with the analytic hierarchy process theory,then gain the weight of each index through the mean of experts questionnairesurvey.Compare the theoretical value with the actual value, lead in the fuzzy theory,then give a mark to each component, add up the product of mark and weight, gain theevaluation system at last;Finally, use the data and the evaluation system from the previous steps as a technical support, put these into the development of the bridge’s technical stateevaluation software, ultimately develop the evaluation software, thus achieve the statusassessment of Qingcaobei Yangtze River Bridge.