铁路客运专线软弱地基低矮路堤采用无梁板桩柱结构技术研究

Research on the Technology of Flat-slab Beamless Pile Structure for Low Embankment of Soft Weak Subgrade of Passenger Dedicated Railway Line

研究目的:通过全面研究,提出软弱地基低矮路堤采用无梁板桩柱结构,保证结构可适应有碴及无碴轨道,达到结构沉降可控,施工方便,造价经济的目的。研究方法:根据相关规范和规定,分析了既有特殊路基和桥梁结构工程,研究了各种构造的优缺点,针对客专拟定可直接用于工程的软弱地基低矮路堤的无梁板式桩柱结构设计参数,采用空间计算模型分析该结构在静力和动力情况下的各项性能指标。研究结果:经静力检算该结构板内力及应力均较小,支撑无梁板采用预制预应力混凝土管桩可行,结构设计按构造布设钢筋即可。经车线结构的动力分析表明该结构可以满足高速行驶列车安全、平稳、舒适性的要求。研究结论:无梁板桩柱作为软弱地基低矮路堤结构可以满足有碴或无碴轨道结构的要求,工程沉降达到可控,技术成熟,施工不必碾压路基,简化了施工环节,方便、环保、节约土地,它的推广应用必将具有良好的社会及经济效益。

Research purposes： structure for low embankment of Through doing overall researches, it is proposed to adopt flat-slab beamless pile soft weak subgrade, which can be suitable for ballast and ballsatless tracks and control the structure＇s settlement with easy construction and low construction cost. Research methods：According to the standards and regulations, the analyses are made for the previous constructions of special subgrade and bridge beam structure and the researches are done on the advantages and disadvantages of all kinds of structures. For the structural design parameters of flat - slab beamless pile structure which can be directly used for the low embankment of soft weak subgrade of passenger dedicated line, the analyses are made for the all performance indexes of the structure under the static and dynamic conditions by using a space calculation model. Research results：The checking calculations show the internal force and stress in the slab of the structure are small, it is feasible to support the beamless slab by prefabricated prestressed concrete pipe pile, and the structure design can be made in accordance with the distribution of reinforcements to be laid. The dynamic analyses of the structures of train and track show the structure can satisfy the requirements of safety, stability and comfortableness for high - speed train. Research conclusions： As a structure of low embankment of soft weak subgrade, beamless slab can satisfy the requirements of ballast and ballastless tracks and can control the structure＇s settlement. Adopting this structure, it is unnecessary to roll the subgrade with the features of simplifying construction procedures, easy construction, aiding environment protection and saving land, so the good social and economic benefits can be obtained by application of this technology.