一种岩体工程黏性流动变形预测的新方法

A NEW METHOD FOR PREDICTING VISCO ELASTIC DEFORMATION IN ROCK ENGINEERING

为了对岩体工程的黏性流动变形进行预测,依据弹性问题位移分量的古萨(Goursat)表达式和弹-黏弹性比拟原理推导相对位移矢量增量公式,并建立变形预报模型,给出变形预报的方法步骤。该方法不是直接求出真实的时间、介质物性参数以及边界条件的值,而是求出一组组合值,通过相对位移矢量增量公式进行预测。无需复杂的应力边界和位移边界条件,能够考虑岩体介质的本构特征,实现长期的两维变形预报。然后将其应用到具有黏弹性解析解的边坡算例中,结果表明:短期预报的精度较高,误差小于10%,长期预报时误差约为23%。最后,结合边坡开挖讨论这一方法的工程适用性,为岩体工程黏性流动的长期两维变形预报提供理论基础和实用方法。

Aimed at viscoelastic deformation prediction in rock engineering, an incremental formula of relative displacement is deduced based on Goursat expression of elastic displacement and elasticity-viscoelasticity analogy principle, and a deformation predicting model with methods and steps is proposed. It does not need the true values of time, boundary condition and physical property parameters of the rock mass, but obtains a group of combination values. The proposed method considering constitutive character of the rock mass can predict two-dimensional long-term deformation without stress and displacement boundary conditions. Then, it is applied to slope engineering, in which the comparison between predicted and measured deformation indicates that the method has high short-term prediction precision with error smaller than 10%, while the error is about 23% in the long-term prediction. At last, the engineering applicability of the method is discussed by an example of slope excavation which provides theoretical foundation and practical method for predicting two-dimensional long-term visco-elastic deformation of rock engineering.