Disease Analysis And Assessment Of Regional Large And Medium-sized Bridges

Bridge is as the throat of transportation facility, due to the aging structure, lack of maintenance, the increase in traffic load and the role and impact of various external factor, they give rise to various diseases and defects. The structural damage of the bridges not only affect the performance of Bridges,but also cause dirreparable loss for countries and people's lives and property.Therefore,checking diagnose andstate evaluation of the service bridge have caught the attention of the bridge world.Focusing on diseases investigation and analysis, technical state assessment of the bridge, the auther mainly do the followings:To the large and medium-sized Bridges serviced in xiangyang city Hubei province as the background, the investigation of 162 old bridges was carried out. It includes inspection and bridge static and dynamic load testing.on this base, we carry on depth analyses for structure and different diseases characteristic of the bridges. Old disease categories, distribution situation of different diseases types, and original design load rating of the bridges were also studied. State and category of Bridges in Xiangyang are evaluated.These studys will play an important role for the large and medium bridges servicing in Xiangyang, especially in disease management and safeguard security. It has great economic value and social benefits.We carry out the bridge evaluation theory analysis and research. Take Guang huahan river bridge as an engineering background, we make a general evaluation for the technology of guanghua hanjiang river bridge according to"Road And Bridge Maintenance Specifications ".The finite element calculation and analysis for Guanghuan Hanjiang River Bridge are done by using the bridge structure analysis software. Dynamic and static load test program about this bridge are made.and then we carried out the dynamic and static load test on the scene. Deflection efficacy coefficient,strain efficacy coefficient and Bridge structure dynamic characteristic parameters are determined Under the conditions of Static Load Test. The bearing capacity of the bridge structure is assessed by comparising test value of strain and displacement and the theoretical value. The technical status of the Guanghua river bridge is comprehensively assessed by using artificial neural network-BP neural network theory.First, we build bridges BP neural network model of Bridge assessment, Collect and collate the data of 60 samples. We scored according to impairment scale of the 17 components, the influence of use function defec tand defect development correction in "Road Bridge Maintenance Standards ".According to standard components of weights, and we got eventually evaluation results of the parts.We created the BP neural network and training after normalization of the Grade evaluation factor. We input components evaluation results of the Guhang huahan river bridge to the trained BP neural network, the evaluation result can be got.The integrated assessment of artificial neural network for the old bridge mke a progress in assessment theory.