Abstract:The principles of time domain reflectometry(TDR) and the properties of electromagnetic wave propagation in coaxial cable are described for the applications of TDR technology to slope monitoring. Based on the shearing tests of three types of coaxial cables,the influences of shear deformation of coaxial cable on TDR signal are studied,and the relationship between reflection coefficient and shear displacement of different types of coaxial cables are summarized. Through experiments on grouted cable assemblies,TDR properties of coaxial cables under different test conditions are investigated and some valuable conclusions are proposed for practical application.