Metallic Damper Simulation

- April 10, 2020 at 6:24 am
  
  mariokeru
  Subscriber
  
  Hi everyone I need your help about some issues about my simulation.
  
  I has been working on metallic dampers for structural seismic control. The principle of hysteretic dissipation is quite simple because is based on plastic strain of the damper plates. I want to simulate the damper under cyclic lateral displacements. The damper is well-known as TADAS metallic damper. The damper has the particularity of having a pin that moves through a slot. Under small displacements the pin moves freely only generating friction forces in the groove. However under a large displacement (i.e. 13 cm) the pin reaches to hit the edge of the slot. I have managed to capture the behavior of the damper for small displacements where the pin has not yet hit the edge of the slot. However I have not been able to record the behavior once this happens. The geometry fails and the deformations become very large. Theoretically when the pin hits the end of the slot there is a significant increase in the force-displacement curve slope. I have tried in many ways to capture the answer at this point but failed. Due to the cyclical nature of the load I cannot calculate what happens in the next cycle of displacement in the opposite direction due to the convergence problem I have. Any recommendation please. These are my configurations for the contact settings in the slot-pin surface region:
  
  PD:
  
  Large Defelction ON
  
  Weak springs ON