铁路既有线桥梁换梁施工中支座处理技术

摘要

In the girder replacement construction of existing railway bridges ,the measures for treating the bearing system concern the girder replacement speed and the users' riding safety.The steel plate girder replacement of the Hanshui Bridge on the Beijing-Guangzhou Railway is taken as the study background ,and a kind of bearing treating technique was introduced.QZ spherical steel bearings were used to replace the curved plate steel bearings ,and installed in the original loca-tions.However ,the skirt of the QZ spherical bearing is larger than that of the original bearings , thus the hole drilling locations should be reserved.Before the replacement of the steel plate girder , the formal hole drilling for the anchoring bolts of the bearings were done ,the temporary bearing cushions were constructed using the pre-embedded steel plate method ,then the temporary bearings were installed and the steel plate girder was replaced ,to ensure the normal operation of the rail-way.Then the cushion reshaping and formal bearing construction were carried out.After the con-struction of the formal bearings was completed ,the load bearing condition of the bearings were converted.The engineering practice proves that it is feasible to replace the steel plate girder during the short blockage of the existing railway line ,and the riding safety of the trains during the con-struction process can be guaranteed.%在铁路既有线桥梁换梁施工中 ,支座系统的处理方案关系到换梁的速度和行车的安全 ,以京广线汉水桥钢板梁更换施工为背景 ,介绍一种支座处理技术.该桥采用QZ球型钢支座替换弧形板式钢支座 ,新支座安装位置与原支座位置相同 ,但其下摆较原支座扩大并预留了钻孔空间.在钢板梁更换前 ,进行正式支座地脚螺栓钻孔 ,采用预埋钢板方式施工临时支座垫石 ,然后安装临时支座并更换钢板梁 ,保证铁路正常运营 ,最后进行垫石改造和正式支座的施工 ,待正式支座施工完成后再进行支座受力转换.实践表明 ,采用该技术在铁路既有线短暂的封锁时间内进行钢板梁更换是切实可行的 ,施工过程中确保了行车安全.