浅层地下水开采对高速铁路工程的影响及对策

研究目的：研究掌握浅层地下水开采引起的地面沉降特征及其对高速铁路工程的影响,提出针对性的防治对策与工程措施,供高速铁路勘测、设计及施工参考。研究方法：结合华北平原地面沉降情况,建立浅层地下水开采引起地面沉降的固结沉降模型。研制离心场中地基抽水的模拟和测量系统,进行了离心模型试验,测量抽水过程中粉土地基孔隙水压力和沉降的变化及分布规律,并对比分析了对不同型式桥梁的影响。研究结果：对浅层地下水开采引起的地面沉降机理进行初步分析,基于离心模型试验结果探讨了浅层抽水引起地基沉降的过程和特征,评价了地基不均匀沉降对特殊桥梁形式的影响,并提出了针对性的防治措施和对策。研究结论：浅层地下水开采造成的不均匀沉降对高速铁路工程的影响较大,需通过控制线路附近地下水开采、采取适宜的工程结构措施加以防治。

The Influence of Pumping Shallow Groundwater on Construction of High-speed Railway and Its Countermeasures

Research purposes:The studies are done on the characteristics of the surface subsidence caused by pumping shallow groundwater and its influence on high-speed railway and the preventive countermeasures and measures are put forward for purposes of providing the reference to the design and construction of high-speed railway.Research methods:Considering the circumstance of surface subsidence of North China plain,the consolidation settlement model is established for surface subsidence caused by pumping shallow groundwater.Centrifuge model tests are conducted to investigate behavior of surface settlement due to pumping groundwater.A drainage system is developed to simulate pumping water during centrifuge tests.The pore water pressure and deformation of silt foundation are measured during the centrifuge model tests of the pumping water to seek their distribution regularity,and the analyses and comparison are made for the influences of them on the different types of bridge.Research results:The analyses of the mechanism of surface subsidence caused by pumping groundwater are made,the behavior and characteristics of ground settlement due to pumping shallow groundwater and its influences on the high-speed railway are discussed with centrifuge model tests,and the countermeasures of subsidence prevention and the engineering measures are also put forward in this paper.Research conclusions:The influence of the asymmetry subsidence caused by pumping shallow groundwater on high-speed railway engineering is serious,but it can be prevented and cured by controlling groundwater pumping and adopting suitable engineering structure.