高铁路基运营期沉降超限治理措施及效果评估

摘要

The control of settlement overrun of high-speed railway subgrade is characteristic of the restriction in time and space,difficult countermeasures and high cost,and may affect the durability of the substructure and train operation,which must be considered in high speed railway maintenance.In order to solve the problem of settlement overrun of high-speed railway subgrade during the operation,the paper puts forward the following measures of integrated engineering management based on field test and theoretical analysis:(1) on both sides of the roadbed,jet isolated pile reinforcement;(2) at the embankment toe,a stress relief hole;(3) at the bottom of the embankment,grout injection through perforated pipe;(4) auxiliary action of pad replacement+fastener raising.Research results are applied in Huning (Shanghai-Nanjing) intercity railway engineering,and the binding settlement test data and TQI values before and after the treatment verify the success of the integrated control measures to provide references for similar engineering practices.%高铁路基运营期沉降超限治理具有“时空”限制严、治理措施难、治理费用高等特点,且可能影响线下结构耐久性和列车正常运行等问题,是高速铁路运营维护中必须考虑的重大问题.为解决高铁路基运营期沉降超限治理的问题,结合现场测试及理论分析的方法,提出集成工程治理的措施.(1)路基两侧:旋喷隔离桩加固;(2)路基坡脚处:设置应力释放孔;(3)路基底部:花管注浆加固;(4)辅助措施:更换垫块+抬高扣件.研究成果应用于沪宁(上海—南京)城际铁路工程实例中,结合治理前后的沉降测试数据和TQI值,验证了该集成治理措施控制效果较好,能够为类似工程实践提供参考.