AE/MS Event Source Location for Circular Hole-Contained Structures Through an Analytical Solution-Based Shortest P-Wave Travel Path.

Acoustic emission/microseismic (AE/MS) source location plays a vital role in the safety monitoring of circular hole-contained structures (e.g., tunnels, pipelines, and pressure vessels). However, traditional methods may obtain a bad P-wave travel path and poor source location accuracy. To handle this, an analytical solution-based shortest P-wave travel path and a grid search-based AE/MS event source location method are proposed for circular hole-contained structures. Moreover, the objective function of AE/MS source location considers the P-wave arrival time system error. Both synthetic tests and pencil-lead break (PLB) application tests in 2D and 3D circular hole-contained structures show the outperformance of the proposed location methods. First, the analytical method obtains an equal or smaller P-wave travel distance than that of the Dijkstra and A* algorithms, which means the analytical method generates better theoretical data. Then, the average location errors of PLB events for the 2D circle-contained rectangle, 3D full circular hole-contained cuboid, and 3D part circular hole-contained cuboid are 0.57 cm, 1.87 cm, and 2.25 cm, respectively. These location results are better than results based on the shortest P-wave paths of the straight line, Dijkstra, and A* algorithms. Moreover, the proposed method solves that former analytical solutions do not consider the thickness of cylindrical shell structures. Highlights: An analytical solution-based shortest P-wave travel path has been proposed for circular hole-contained structures. The acoustic emission/microseismic source location objective function considers the P-wave arrival time system error. The average location errors of pencil-lead break events for circular hole-contained structures are within 2.25 cm. The analytical solution-based location method obtains better location results than methods based on the straight line, Dijkstra and A* algorithms. [ABSTRACT FROM AUTHOR]