盾构隧道管片接头抗剪力学性能研究

摘要

Three sets of shear loading tests for circumferential segment joints of the Nanjing Yangtze river tunnel were carried out, including shearing without bolts, ordinal shearing with bolts, and reverse shearing with bolts. The mechanical behavior, deformations, and failure characteristics of the segment joints were investigated. The static friction coefficient of the concrete contact faces was determined. It was concluded that the shear resistance of the segment joints is mainly mobilized by the concrete contact faces and the failure characteristics are ductile shear damage of the oblique bolts. The segment internal forces were calculated by FEM. Results showed that the shear/axial force ratio of segment joint is less than the friction coefficient of the concrete contact faces, that dislocation will not occur between the segments, and that the structure is stable.%通过对南京长江盾构隧道环向管片接头进行的三组原型抗剪(无螺栓剪切、有螺栓逆剪和有螺栓顺剪)加载试验,分析研究了管片接头在剪力作用下的受力、变形和破坏特征,给出了管片接头混凝土接触面的静摩擦系数,得到了接头剪力主要由混凝土接触面承担、破坏形式为连接斜螺栓剪切延性破坏的结论.通过对管片结构的有限元数值模拟计算得出:接头处的剪力与轴力比小于接缝面的摩擦系数,管片不会发生相互错动,结构是稳定的.