期刊名称：International Journal of Distributed Sensor Networks
印刷版ISSN：1550-1329
电子版ISSN：1550-1477
出版年度：2018
卷号：14
期号：2
页码：1-14
DOI：10.1177/1550147718759234
出版社：Hindawi Publishing Corporation
摘要：Connection looseness phenomena of steel grid structures might induce issues of lowering integrity, large deformation, even total collapse of the structures. The goal of this article is to propose an evaluation method for bolt-sphere joint looseness of steel grid structures using piezoceramic guided wave–based method through experiments and numerical simulations. A single bolt-sphere joint looseness experimental model is established and tested, considering grid member connection angles of 0°, 45°, 90°, and 180°, respectively. Then, multiple bolt-sphere joint looseness detection tests by selecting six kinds of cases for a steel grid structure model are performed. Piezoceramic patch arrays bonded on the surface of grid members are used as transducers to generate and receive detection guided waves, and external torques are applied to indirectly simulate the bolt-sphere joint looseness effect. The experimental results show that the bolt-sphere joint looseness impact on the ultrasonic wave energy attenuation has a nonlinear regularity. Based on the regularity, an evaluation method and key techniques for the bolt-sphere joint looseness detection based on guided wave energy are proposed and experimentally validated. To further clarify the bolt-sphere joint looseness detection mechanism, the ABAQUS software is used for a finite element analysis of the single bolt-sphere joint looseness evaluation. The numerical and experimental results match well, verifying the feasibility of the proposed method.
关键词：Connection looseness detection; piezoceramic transducers; steel grid structures; structural health monitoring; lead zirconate titanate–based guided waves
