CMP和CFG组合型桩复合地基载荷作用特性研究.pdfVIP

第十一届土力学及岩土工程学术会议 中国·兰州 2011 年 8 月 16—19 日 文章编号：(2011) 07 ―20 CMP 与 CFG 组合型桩复合地基载荷作用特性研究 李龙起，罗书学 (西南交通大学 土木工程学院，四川成都 610031) 摘 要：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，结合 Hardening-soil 本构模型对地层参数进行了反演分析和计算， 通过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。 关 键 词：CMP ；CFG 桩；组合型桩复合地基；载荷作用 Study on loading behavior of composite foundation integrated by Cement Mixing Piles and CFG piles 1 1 Li Longqi ，Luo Shuxue (1.School of Civil Engineering，Southwest Jiaotong University，Chengdu，Sichuan 610031，China) Abstract ：Based on the main feature of deep-soft soil region, adopting cement mixing piles and CFG piles of different stiffness and length to deal with the ground treatment is an innovation. Based on the Harbin-Dalian passenger dedicated railway, this paper have waged parameter inversion in combination with the Hardening-soil constitutive model, at the same time site test and numerical analysis have been adopted to study the loading character of this kind of composite foundation. The result show that CFG piles undertake most load of the subgrade, 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. Key words ：cement mixing piles ；CFG piles ； combined piles composite foundation ；loading behavior 在深厚软土分布地区修筑高速铁路路基工程，往往会遇到土体含水量大、承载力低的问 题，常需要采用地基处理方法改善其承载特性。但有时在遇到较为复杂恶劣的地质状况时， 仅采用CFG桩地基处理形式无法