Analysis of the in-plane bending vibrations of cylindrical shells subjected to white noise excitation through a connecting tube

Abstract

Recently, the deteriorated buried water mains are increased, as a result, many accidents (leakage, burst and so on) are occurred. Owing to prevent accidents, efficient maintenance based on Non-Destructive Inspection (NDI) is required. However, there is no existing effective technology for evaluate buried main. Therefore, it is necessary to expose water mains in the inspection by the past technology. In this paper, we proposed the no-exposure diagnosis method through the connecting pipe. To develop an inspection equipment for estimating the deteriorated condition of water mains, the in-plane bending deformation vibration modes are induced by white noise excitation through connecting pipes. Furthermore, the finite element analysis was performed for understanding the eigenfrequencies and the modal shape of the coupled vibratory system. Moreover, the simplified model was derived based on the coupled ring model, the eigenfrequencies by an above model were good agreement with the calculation values by finite element analysis.