复合地基垫层刺入量模型试验与计算方法研究  

Experimental Research and Calculation Methods of Cushion Penetration in Composite Foundation

作　　者：朱小军[1,2] 孔伟阳 费康[1] 许朝阳[1] 李文帅[1] Zhu Xiaojun;Kong Weiyang;Fei Kang;Xu Zhaoyang;Li Wenshuai(School of Civil Science and Engineering, Yangzhou University, Yangzhou, Jiangsu 225127, P.R. China;School of Civil Science and Engineering, Southeast University, Nanjing 210096, P.R. China)

机构地区：[1]扬州大学建筑科学与工程学院,江苏扬州225127 [2]东南大学土木工程学院,南京210096

出　　处：《地下空间与工程学报》2018年第2期412-419,共8页Chinese Journal of Underground Space and Engineering

基　　金：江苏省高校自然科学基金(15KJB580013);国家自然科学基金(51278446)

摘　　要：为了研究复合地基垫层刺入量有关因素,通过可视化模型箱对不同垫层厚度、密实度、桩径以及桩帽的刚性桩复合地基进行室内模型试验。利用数字图像无标点量测技术,对在加载过程中垫层土体颗粒的位移场进行观测与分析,研究了复合地基垫层的位移场与变形模式,得到了垫层的刺入量、变形范围以及滑动面位置与形状。根据球孔扩张理论推导出垫层刺入量的求解公式,并与模型试验数据进行了对比分析,验证了理论方法的合理性,且理论计算结果与试验数据吻合较好。垫层刺入量的研究对复合地基垫层厚度、桩径等设计具有一定参考价值,垫层刺入量可协调桩土的荷载分担,使桩土共同承担上部结构荷载,为复合地基沉降研究提供了理论依据和数据支持。In order to study the factors of cushion penetration in composite foundation. The model tests of rigid pile composite foundation were carried out in a visual box,considering different cushion thickness,compactness,pile diameter and pile cap. The digital speckle correlation technique was used to observe and analyse the displacement field of soil particles in cushion during the loading procedure. The displacement fields and deformation modes of cushion in composite foundation were researched. The penetration,deformation scope,sliding position and shape of the cushion were obtained. Based on spherical cavity expansion theory,a formula for solving the penetration in cushion was derived. The theoretical calculation results were compared with the model test data. The rationality of the method was verified,and the theoretical calculation results agreed well with the test data,which could meet the engineering of accuracy. The research of cushion penetration is helpful to design the cushion thickness and pile diameter of composite foundation. The cushion penetration can coordinate load sharing of pile-soil and bear the load of superstructure,which can provide theoretical basis and data support for the research of composite foundation settlement.

关 键 词：复合地基 垫层 刺入量 模型试验 

分 类 号：TU473.1[建筑科学—结构工程]