Maintenance And Construction Monitoring Of BeiDa Bridge In Dalian

After seventy or eighty’s of last century there has been a gradual emergence of the suspension bridge. Suspension bridge has the characteristics of large span capacity, high technical requirements, complicated. Because of starting late and the design theory and technology not particularly perfect, these bridge constructions have been operated for twenty or thirty years. Suspension bridge in service began to appear a lot of diseases during operating. Research on maintenance and reinforcement of suspension bridges is becoming more and more necessary.Based on Beida Bridge in Dalian maintenance engineering, the bridge appeared a variety of diseases, such as excess deflection of main girder, cable, tower top, main cable saddle and sliding saddle and component corrosion during operating in the past thirty years. In this paper, combined with the maintenance and reinforce and construction monitoring are studied. The main work of this paper are as follows:(1) Introducing the basic characteristics of suspension bridge, common diseases of suspension, research status of maintenance and reinforcement technology for suspension bridge. At the same time, the theoretical calculation of the structure of the suspension bridge is given, which is mainly from three aspects of the elastic theory, deflection theory and nonlinear theory.(2) To collect the information, including the design drawings and tests, in order to obtain the status of the bridge, to provide a basis for the subsequent structural analysis.(3) In allusion to the defect existing in Beida Bridge, analysis the cause of disease and the effect on the structure response caused by the diseases, giving the bridge maintenance reinforcement design, mainly including the bridge deck transformation, erection of main cable and suspender replacement.(4) Using the software midas to build a spatial model for Beida Bridge, determining the bridge built in the early state of the bridge according to the design drawings. On the basis of this and the state of active bridge I build a new model. Verifying the model is reasonable according to the main truss shape, main cable saddle deviation and splay saddle deflection. Use this model as the foundation of theoretical analysis and maintenance reinforcement calculation.(5) The finite element model was established to simulate the whole maintenance and reinforcement process, and the measured values were compared with the measured value of the construction monitoring. Mainly from the main truss shape, bulk cable saddle offset, tower displacement cable saddle deflection, internal force of the hanger rods, main cable force data were analyzed. The positive significance of the maintenance and reinforcement scheme to the bridge disease is put forward, and the reinforcement scheme is beneficial to improve the condition of the bridge.(6) After the maintenance and reinforcement of the construction is completed, the state of the bridge safety assessment, to provide a basis for the future operation of the bridge.