Practice And Numerical Analysis Of Maintenance And Reinforcement Of Xiangjiang River Highway Bridge

With the development of society and economy, transportation make a spurt ofprogress, a lot of new bridge and old bridge that Their original design standards arelower together stepped into large traffic operation period. Bridges subjected tolong-term high traffic, heavy loads during the operation, since the bridge usually lackthe necessary maintenance and repair, fatigue, aging, disease and other problemsbegan to emerge in the operation, a number of overloaded vehicles is illegal totransport, it is aggravated development of bridge disease, thus cause different degreesof bridge damage, and even endanger the safety of the bridge. According to thestatistics of the Ministry of transportation, In2010the dangerous bridge is about93500,22,000dangerous bridge transformation was complete from2001to2012, inspite of the yearly transformation, however, our county is still a considerable numberof dangerous bridge, thus strengthening the dangerous bridge reinforcement andrepair and Research imminent. In this paper, Yunji Xiangjiang highway bridgestrengthening and repair project as an example, made the following main research:⑴This paper analyzes the domestic and international old and dangerous bridgeresearch status, the statistical analysis showed that the arch bridge mainly havesuspender ropes corrosion, the deformation of the upper and lower anchor head (a),rust damage and other diseases.⑵Through the detection of Yunji Xiangjiang highway bridge disease, found thatsome hanger corrosion, some cold cast anchor pier head rusting, asphalt felt basedamage in box rib arch bridge panel and the cover beam,5pier with transverse cracks,1~4pier cap beam with vertical cracks, and provide basis for strengthening design,construction.⑶Using Midas software modeling, analyzes internal force of main arch rib of archfoot,1/4,3/4arch, vault on the bridge working condition and analyzes temperaturestress in heating and cooling, recommended additional expansion joints at the5thmendun.⑷For cracks, we used plastic injection, stickers steel，for oil felt bearing disease,we add rubber bearing installation by the lifting method, for cable corrosion, rust ofthe anchor head and other diseases we use the suspender replacement, according to"equivalent replacement" the principle we replaced suspender by step by stepimplementation of unloaded cable and the gradual temporary cable load synchronouscontrol method⑸We establish model for theoretical modal analysis by Midas, and obtains thetheory value. Through the load test of the bridge under the most unfavorable positionoffset load, limit state load test. we obtains deflection, coefficient of strain by thestatic load experiment, obtains modal test results, impact coefficient by the dynamicload test, and they are compared with theoretical value. The measured results showthat Yuji bridge bearing capacity is restored to the original design of the state.