连续曲线箱梁桥端横梁裂缝原因分析

Analysis of Crack on End Cross Beam in Continuous Curved Box Girder

采用ANSYS有限元块体单元来模拟某连续曲线箱梁桥的端横梁,对其在施工期间产生裂缝的原因进行分析计算。计算表明端横梁开槽使截面削弱是导致裂缝的主要原因,成桥封锚后拉应力明显减小,裂缝情况得到很大改善。成桥后的端横梁静载试验表明,在活载作用下典型裂缝的长度和宽度都没有明显的增加。因此,在设计中有必要针对开槽的端横梁预应力张拉工况进行应力验算。

This paper simulates end cross beam in continuous curved box girder by means of solid finite element in a program named ANSYS and analyses the reason of its crack during construction. The results show that notched end cross beam consequently weakening the section causes crack. The region of tension stress is obviously reduced and the status of crack is better improved after sealing the anchorage zone. The length and width of typical crack of end cross beam after the bridge built don't obviously grow under the live load test. Therefore, it is quite necessary for design department to do stress checking calculation in the case of stretching prestress on notched end cross beam.