Model Validation of Loose Bolted Joints in Damaged Structural Systems

 

Joel R. Feenstra, Dept. of Mechanical Eng., Michigan Technological University

Tyler F. Winter, Dept. of Mechanical and Aerospace Eng., University of Missouri-Rolla

Brandon R. Dierschke, Dept. of Mechanical Eng., Texas A&M University

Alan Barhorst, Dept. of Mechanical Eng., Texas Tech University

 

The bolted or riveted lap joint is a common fastening technology for structural members. When a joint becomes worn the joined members can move in a nonlinear fashion relative to each other as well as impact each other and the lap joint plates. For low frequency bending modes the system can experience sticking or frictional sliding motion at the finite number of contact points in the joint. This research validates a theoretical frictional contact impact model of a typical loose bolted joint. For each of the different contact and motion regimes damping parameters were determined. Contact patches, strain gauges, a force transducer, and accelerometers were used to measure a test device. The results were then compared to the simulation results. A video of the experimental joint motion was also compared to animations of the simulated joint. The simulation parameters were adjusted to produce a better prediction of the behavior of the test device.