摘要
为研究初始裂缝尖端起裂的条件和所需注水压力,依据断裂力学的复合型裂纹的脆性断裂理论,建立了裂缝尖端力学模型,给出了计算方法。并通过数值模拟分析了影响尖端裂缝起裂的因素,揭示了初始裂缝尖端在注入高压水后形成高拉应力集中,初始裂缝尖端在拉应力作用下起裂,注水压力越大拉应力集中程度越大。通过进行现场试验,取得了良好的效果,并验证了理论分析和数值分析的可行性。
For researching crack initiation condition and water injection pressure needed,this paper built up a mechanics model of crack tip based on crisp fracture theory of compound crack.It applied numerical simulation to analyzing influence factors of crack initiation.Results showed that high stress concentration at initial crack tip after high-pressure water injected and initial cracks developed under tensile stress.Water injection pressure was positive related with tensile stress.Practical test showed good effect and verified simulation results.
出处
《煤矿开采》
北大核心
2010年第4期4-7,共4页
Coal Mining Technology
基金
国家重点基础研究发展规划(973)资助项目(2005cb221501-03)
国家“十一五”科技支撑计划资助项目(2006BAK03B06,2006BAK04B02)
国家自然科学基金资助项目(50490273,50474068)
关键词
定向水力致裂
坚硬顶板
初始裂缝
控制孔
directional hydraulic fracture
hard roof
initial crack
controlling dill
