TDR Manufacture And Its Application In Distributed Detection Of Rock-soil Deformation

Geotechnical disasters such as landslides and debris flow have caused great threat to the safety and property of people. There are different degrees of rock-soil deformation before the occurrence of the geotechnical disaster. Monitoring the deformation of rock-soil is an important way to prevent and study the geotechnical disaster. Researchers developed many geotechnical disasters monitoring technology, such as GPS measurement technology, automatic total station instrument observation technology, fiber sensing technology, pull sensing technology, time-domain reflection measurement technology based on coaxial cable, etc.Aiming at some problems in the above monitoring techniques, a new method for the monitoring of rock-soil deformation has been proposed. The method is a deformation distribution measurement technique which is composed of the spiral parallel transmission line and time domain reflection technology. The deformation distributed measurement and calibration system is designed. The system is composed of spiral parallel transmission line, time domain reflection device, drawing device and master computer. Time domain reflection device which is composed of a narrow pulse circuit, return signal conditioning circuitry and high-speed sampling module is developed. The tensile device of the system is used to stretch of the whole spiral line of 162cm and stretch positioning of the spiral line of 500cm, at the same time, the time domain reflection device of the system is used to test the spiral line, and using the partial least squares to model the measurement data of the two groups respectively. The prediction result is displayed by the PC. Based on the above two experiments, a distributed measurement experiment was carried out on the parallel transmission lines, and the deformation position and shape variable of each test point were accurately predicted.The experimental shows that the proposed method can accurately predict the tensile and tensile strength of the parallel transmission lines, and it solves the problem that" the measured place not be changed and the changed place can not be mesured". what's more, it has a larger measurement range than the optical measurement method of slope.