水泥掺入量对劲性复合桩界面剪切特性的影响  

Effects of cement content on the interfacial shear characteristics of rigid composite pile

作　　者：朱锐 周峰 盛强 卜任杰 潘春宇 范磊 陈廷柱 ZHU Rui;ZHOU Feng;SHENG Qiang;BU Renjie;PAN Chunyu;FAN Lei;CHEN Tingzhu(College of Transportation Engineering,Nanjing Tech University,Nanjing 211800,China;Jiangsu High-Speed Railway Safety Engineering Technology Development Center,Nanjing 210031,China;China Construction Installation&Energy Engineering Group Co.Ltd.,Nanjing 210046,China;Nanjing Jiangbei Public Construction Engineering Co.Ltd.,Nanjing 211031,China)

机构地区：[1]南京工业大学交通运输工程学院,江苏南京211800 [2]江苏省高铁安全工程技术研究开发中心,江苏南京210031 [3]中建安装集团有限公司,江苏南京210046 [4]南京江北公用建设工程有限公司,江苏南京211031

出　　处：《南京工业大学学报（自然科学版）》2023年第5期546-553,562,共9页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：江苏省基础研究计划(自然科学基金)青年基金(BK20220356);教育部高铁安全协同创新中心、江苏省高铁安全工程技术研究开发中心项目(TAQ202208)。

摘　　要：劲性复合桩是将刚性桩与柔性桩或散体桩经复合施工形成的具有互补增强作用的桩,但其水泥土水泥掺入量与界面剪切位移等指标的相互关系尚不够明晰。对此,开展劲性复合桩内界面(混凝土水泥土)、外界面(水泥土桩周土)的界面剪切试验,研究水泥掺入量对劲性复合桩界面剪切特性的影响,得到不同水泥掺入量下的界面性能参数。结果表明:内界面和外界面的剪切强度与法向应力关系符合库仑定律,两个界面因为水泥的黏结效应,都拥有一定黏聚力,提高水泥土水泥掺入量可以提高界面的剪切强度与黏聚力,两个界面的极限剪切位移随水泥掺入量与法向应力的提高近似线性增大,且外界面处极限剪切应力相较内界面受施加的法向应力影响更甚。The rigid composite pile is a kind of pile with complementary reinforcing effect formed by composite construction of rigid pile and flexible pile or bulk pile.However,the relationship between cement soil content and interface shear displacement is not clear enough.In this regard,the interfacial shear tests of the internal interface(concrete-cement soil)and the external interface(cement soil-pile soil)of the rigid composite pile were carried out to study the influence of cement content on the interfacial shear characteristics of the rigid composite pile,and the interface performance parameters under different cement content were obtained.Results showed that the relationship between the shear strength and the normal stress of the inner and outer interfaces conformed to Coulomb s law,and the two interfaces had a certain cohesion due to the bonding effect of cement.The shear strength and cohesion of the interface could be improved by increasing the cement content of the cement soil.The ultimate shear displacement of the two interfaces increased approximately linearly with the increase of the cement content and the normal stress,moreover,the ultimate shear stress at the outer interface was more affected by the applied normal stress compared to the inner interface.

关 键 词：劲性复合桩 剪切特性 水泥土 传力体系 界面剪切强度 剪切位移 水泥掺入量 

分 类 号：TU473.1[建筑科学—结构工程]