ICSV26

Buried piping systems play a very important role in modern societies, especially in transporting fluids and gases for everyday use. Within these systems, plastic pipes have been widely used in recent decades because of their relatively low failure rates compared against other type of pipes in service. Unfortunately, the records of these underground utilities are often inaccurate and incomplete. Problems associated with inaccurate location of buried pipes are exacerbated in the presence of rapid development of urbanization, which increases both the difficulty and economic costs of excavation work. In response to this, trenchless technologies have been developed and shown effective in locating buried piping systems. In particular, acoustic detection method is considerably promising in locating plastic pipes. By applying acoustic excitation on one part of the pipe and analyzing the ground surface vibration, the location of the buried pipe can be determined. Whilst there are existing studies relating to plastic water pipes in this field, limited research has been carried out on buried gas pipes detection. Based on the model of buried fluid-filled pipe, an analytical model of buried plastic gas pipe will be studied in this paper. The analytical solution and numerical simulation results of the mode waves will be presented and their characteristics will be analyzed. Moreover, in our proposed model, the ground surface vibration directly above the pipe will be expressed as the result of radiated conical waves resulted from the propagation of the specific mode wave inside the pipe. Hence, there is no need to approximate conical waves as plane waves, which will make our analytical solution more accurate. This work can provide theoretical insight to acoustic detection techniques used for locating buried pipes.