【作者】 王凤恩；

【导师】 李同春；

【作者基本信息】 河海大学 ， 水工结构工程， 2007， 硕士

【摘要】 本文介绍了两种处理软基的常用方法，打桩和加筋技术。在用桩处理软土地基的过程中，大多使用群桩。早期的群桩基础的竖向承载力就是按单桩的承载力简单的叠加起来的。但是竖向荷载作用下的群桩基础，各基桩的承载力发挥和沉降性状与相同情况下单桩的承载力有显著的差别，本文建立了桩一土一承台共同作用的有限元模型，计算中采用了梁单元代替实体桩及对桩周边土局部加密的方法，并对该方法进行了算例验证，验证了该方法的正确性、可行性，提高了桩土相互作用的计算速度。计算了不同桩长、不同桩径、不同桩数情况下的单桩和群桩的竖向承载能力，对桩基础的承载能力与竖向位移直接的关系进行了探讨，得到了一些对桩基础设计和研究有意义的结论。 对于加筋土本文介绍了将土体与筋带独立划分单元，不考虑筋带单元与土体的节点重叠，将土体单元节点的位移变量为基本变量。在筋带节点的土体单元内部设置与筋带节点数目相同的土体附加节点，这些节点的位移由包含相应节点的土体单元的位移插值得到。并把此方法应用到深圳河治理B段挡土墙工程的有限元计算中去。 研究成果对加筋结构的进一步推广应用和工程实践水平的提高在一定程度上起到了积极的作用。也为今后处理软土地基中的加筋结构与软基相互作用的数值计算提供了一套较完整的方法。更多还原

【Abstract】 This paper introduced two kinds process the soft earth base the commonly used method, piles and reinforced earth the technology. In uses the pile stabilized soft earth base, mostly uses the group piles. Early , the group pile foundation vertical supporting capacity is according to the single pile supporting capacity simple superimposition. But under the vertical load function , it’s remarkable different between group piles foundation and single pile in piles supporting capacity display and the subsidence character .This paper establishes the finite element model of pile Groups-Soil-Pile Cap Interaction, usesing the beam unit to replace the conrete pile and Interpolation Method is used to densification mesh of pile peripheral earth and a example are presented in the paper to tested the new method is accuracal、 feasible, the new method enhanced the computation speed. Calculated the model of different pile long, pile diameter, pile number situation single pile and group piles vertical bearing capacity, discussed the pile foundation bearing capacity and the vertical displacement direct relations, and obtained some significance conclusions to the pile foundation design and the research.About reinforcement earth , divideing independently the soil elements and the reinforcement elements, not considering the node overlaps, these node of soil element displacement is the basic variable. Establishment the new nodes which is same position with the reinforcement node and these nodes displacement are determined by contains corresponding the soil body node displacement interpolation .And applies this method to Shen Zhen He river B section treatment reinforced earth-retaining wall project .The research results played a positive effect, to extent to the reinforcement structure further promoted application and the project practice level enhancement .It provided a complete methods to simulate pile groups-soil更多还原