Single Beam Model For Predicting Intrusion In Pipelines

Abstract

This paper examined pipeline safety and developed a predictive model for intrusion-induced failures. A mathematical model for predicting intrusion has been formulated. A typical pipeline structure has been idealized as a circular beam resting on an elastic soil foundation. Intrusion was considered to consist of hammering and cutting activities. From the solution obtained for the model a feedback control algorithm has also been propounded which could in turn help in designing surveillance instruments which can assist in mitigating the problem. The feasibility of introducing displacement sensors into a typical pipeline to enable collection of spatially distributed modal response was explored in an example. The idea was that sensors react to intrusive load signals and could be configured to measure physical parameters (displacement, velocity or acceleration response). A point sensor was used to simulate the response in a 2 m segment of the pipe to intrusive drilling force. The response at intervals of 2 s was randomly sampled at 0.00, 0.60, 1.10, 1.40 and 2.00 m and displacements indicated were 0.00, -1.25 x 10^-3, -1.82 x 10^-3, -1.56 x 10^-3, 0.00 m, respectively. A peak displacement of around -1.83 x 10^-3 m was obtained at the point of intrusion.