Abstract:Many serious disasters are resulted from high-speed landslides,which take huge energy and high speed as their characteristics. So it¢s important to research the mechanism of high-speed landslides,sliding velocity and time to predict the damages. Based on the theory of eco-environmental catastrophe chain and mechanical model of sliding mass which takes water into account,a new calculating formula which is used to estimate the sliding velocity and sliding time is proposed;and the transformation and dissipation of energy during sliding are also involved in the formula. The coupling performance of pore water and atmospheric damping is considered in this formula;and it can fit actual situations very well. It can be used to predict the damage of high-speed landslides so as to offer theoretical proof to the design and construction of projects.