干湿循环作用下露天矿边坡岩石损伤能量演化分析

Energy Analysis of the Evolution of Open-pit Slope Rock Damage under the Effect of Wetting and Drying Circulation

水位升降对露天矿坑边坡岩石强度产生明显的弱化,因此,干湿循环对岩质边坡稳定性分析具有重要影响。通过不同干湿循环次数下的岩石单轴压缩试验,基于不可逆热力学损伤理论,分析外力总功、弹性能以及能量耗散之间的内在关系。实验表明:外部载荷对岩石所做总功,一部分转化为岩石弹性变形能,还有一部分以能量耗散的形式导致岩石发生不可逆的损伤。通过岩石室内试验,研究花岗岩力学性质变化规律,建立基于能量耗散原理的不同循环次数下花岗岩损伤演化方程。室内试验分析和理论研究表明,基于能量耗散原理建立的不同干湿循环效应下岩石损伤演化方程,可以较好地描述岩石的损伤演化。

The fluctuation of water level on the open pit slope rock strength have a significant weakening,the wetting and drying circulation on rock slope stability analysis has important implications. By uniaxial compression tests of rock under different wet and dry cycles,based on thermodynamics of irreversible damage theory,the total work force,elastic energy and the intrinsic relationship between the energy dissipation were presented. Experimental results show that: the external loads to the total work done by the rock,part of the rock into elastic deformation energy and partly to the energy dissipation in the form of rock lead to irreversible damage. Through the rock laboratory tests,study changes of mechanical properties of granite,set up under the granite damage evolution equation based on the principle of energy dissipation in different cycles. Laboratory test analysis and theoretical studies show different effects of wet and dry cycles based on energy dissipation principle established rock damage evolution equation can describe the damage evolution of rock.