Numerical Simulation of Bolt Looseness Monitoring Based on Impedance Method

A monitoring method based on impedance method was researched for bolt looseness of steel structure. First, the basic principle of impedance method and its characters were introduced. Then, the root mean square of admittance (reciprocal of impedance) real part was used as the index to identify the damage degree. At last, a numerical simulation research on the monitoring of bolt loosen based on impedance method was hold by finite element analysis software. In research, a model of bolted connection joint of steel structure was built according to subsistent test by finite element method (FEM) software, and different levels of bolt loosen were simulated. The researched results had shown that the impedance method is efficient for the monitoring of bolt loosen. And the damage index could reflect damage tendency well. The simulation results are good agreement with test.