平台对危岩体失稳后运动有很好的减速拦阻作用,是危岩体防治的有效措施。设计了平台停积作用试验,采用多元非线性回归模型对滚石在平台上的停留位置以及平台平均阻力系数进行研究,分析停留位置和平均阻力系数分别与滚石质量、形状、滚石到达平台时的速率以及平台表面粗糙程度等因素之间的关系以及各因素的相关性,并对多元非线性回归模型进行预测;同时,特别分析了滚石质量对停留位置的影响。结果表明:(1)滚石停留位置和平均阻力系数与滚石质量、形状、滚石到达平台时的速率以及平台表面粗糙程度等影响因素的关系均可采用多元非线性回归关系式表示,并且预测值与实际值可较好吻合;(2)滚石质量、初始位置(边坡高度)和平台表面粗糙程度对滚石停留位置有较大影响,表现为滚石质量越大,边坡高度越大,滚石在平台运动的距离越远。所得结果为将平台作为危岩体防治措施时确定平台的宽度提供依据,对坡面地质灾害的防治有指导意义。
Platform has a good function to baffle dangerous rock masses movement after falling. Based on stopping and accumulation effects of experiments of platform on rolling rock blocks, the stopping position and the average resistance coefficient of rock blocks on platform are analyzed by using the multivariate nonlinear regression model. The relations between the stopping position and the major factors such as the rock block mass, the rock block shape, the velocity of the rock block just falling on the platform, and the roughness of the platform surface, are analyzed. And the relations between the average resistance coefficient and these factors are also analyzed. Then the factors relativity is analyzed. Moreover, the multivariate nonlinear regression model is predicted. Finally, the effect of rock block mass on the stopping position is analyzed specially. The following results can be drawn. (1) The stopping position and the average resistance coefficient are influenced by rolling rock block mass, shape, velocity when just arriving at platform, and the roughness of the platform surface. Their relations can be expressed by the multivariate nonlinear regression formulas. And the predicted stopping position and average resistance coefficient by the method nearly coincide with practical ones. (2) The mass of rolling rock block, initial position(slope height), and the roughness of the platform have a certain influence on the stopping position. In other words, the stopping position of the rolling rock block and its mass accord nearly with power function. The more the rolling rock block mass is, the higher the slope height is, and the longer the displacement on the platform is for same mass of rolling rock block. Then new feasible methods to prevent potential unstable rock masses are put forward. The results are helpful to make out a draft for geohazards prevention.