CMP与CFG组合型桩复合地基载荷作用特性研究

针对深厚软土层工程特性较差的特点，使用刚度、长度各异的水泥搅拌桩(CMP)与CFG组合型桩进行地基处理是一种新的尝试。以哈大客运专线某工点地基处理为依托，采用Hardening-Soil本构模型对地层参数进行了反演分析和计算，结合现场试验和数值模拟等手段对这种新型组合型桩复合地基荷载传递特性进行了研究。研究表明，CFG桩是承受上部荷载的主体，CMP起到改善流塑状土体特性、保证基础完整性的作用；通过CMP的设置，CFG桩桩侧的负摩阻力弱化，从而提高了复合地基的整体承载能力。

Study on loading behavior of composite foundation integrated by cement mixing piles and CFG piles

On account of the main feature of deep soft soil region, it is an innovation on adopting cement mixing piles and CFG piles of different stiffness and length to deal with the ground treatment. Based on the Harbin-Dalian passenger dedicated railway, this paper have conduct parameter inversion in combination with the Hardening Soil constitutive model, while site test and numerical analysis have been adopted to study the loading character of this kind of composite foundation. The result shows that CFG piles undertake most load of the superstructure, while cement mixing piles take the task of improving the characters of plastic-like flow soil and keeping the integrity of the system. Moreover, the cement mixing piles improve the CFG capacity by weakening the negative friction and the total capacity of composite foundation has been enhanced in turn.