The Dynamic Interactions in High-Rise Vertical Transportation Systems

High speed and high capacity vertical transportation (VT) installations in the modern built environment service buildings of nearly 1000 m tall. Tall buildings are susceptible to large sway motions when subjected to wind loading or earthquake excitations. The low frequency sway motions cause resonance interactions in lift car/ counterweight suspension system, compensating ropes and overspeed governor ropes. This leads to poor ride quality and a high level of dynamic stresses which may result in damage to the installation. This paper presents the systems engineering approach to predict and quantify transient and steady-state resonant vibrations taking place in high-rise lift applications. The results and conclusions presented in the paper demonstrate that a good understanding of the dynamic behaviour of VT systems is essential for developing design strategies that minimize the effects of adverse dynamic responses so that the installation will operate without compromising the structural integrity and safety standards.