Structural Dynamics of Elevator Counterweight Systems and Evaluation of Passive Constraint

Abstract

Structural dynamic responses imposed by large base excitation and the effectiveness of an intermediate constraint in elevator counterweight systems are studied. A nonlinear contact finite element with nonlinear stiffness and amping approximated by polynomial functions is developed to simulate the dynamic contacts in elevator counterweight systems. A passive vibration control device—intermediate constraint—is proposed and evaluated. Analysis results show that the number of consecutive contacts increases as the excitation frequency decreases; large contact force can occur in current design practice, and constraining the motions of two rails by intermediate ties can reduce the contact load by 40%.