温度应力对裂隙岩体强度的影响研究

RESEARCH ON INFLUENCE OF THERMAL STRESS ON FRACTURED ROCK MASS STRENGTH

从断裂力学理论出发,定量分析高于常温的温度场中温度应力作用对含有单条裂隙、单组裂隙以及多组裂隙岩体强度的影响规律。由理论角度,从弹性力学着手,采用解析的方法以等效荷载法,利用叠加原理,将代表性体积单元中单条裂隙温度应力的表达式叠加到代表性体积单元的单条裂隙的结构荷载中,推导岩体裂尖处在一定温度应力作用下断续裂隙介质的细观断裂强度表达式,简便有效地将细观尺度如裂隙长度、方向等与宏观条件如温度、强度有机地结合起来,完善现阶段研究对于裂隙岩体强度表达形式的不足,引出一个能够全面展示宏、细观层面及考虑温度影响因素,综合表达裂隙岩体强度稳定性的探索新思路。最后通过相关试验结果,验证所建立的公式具有较高的可靠性。

Based on the theory of fracture mechanics, influence law of rock strength with single fracture, a set of fracture and multiple sets of fractures under the action of temperature stress caused by the temperature field higher than room temperature field is presented quantitatively. In the view of theoretical point, starting from elasticity mechanics, using the analytical method such as equivalent load method and principle ofsuperposition, the thermal stress expression of a single fracture is added to the structural load expression of a single expression in representative volume element（REV）. The micro-fracture strength expression of intermittent fractured media, of which crack tip of rock fracture is affected by certain temperature stress, is deduced. The microscale such as fracture length and fracture direction and so on is combined effectively and organically with the macroconditions such as temperature and strength. The strength expression of fractured rock at this stage has been improved. A exploration of new idea which could demonstrate the macro-, micro-levels and consider temperature factor fully and describe rock stability comprehensively is elicited. At last, the relevant experimental results show that the formula established has high reliability.