摘要
为对水力压裂煤体裂缝的起裂判据作定量计算,根据弹性力学理论,分析了注水钻孔周围的应力状态,给出了水平和垂直裂缝产生时注水压力的计算模型;探讨了裂缝扩展的方向以及其扩展所需要的泵注压力;采用自制的高水载荷下煤体裂隙生成及延展模拟装置在实验室模拟了不同围压和轴压加载下条件下煤体起裂的临界注水压力及裂隙生成和延展的方向.实验研究表明:泵注压力克服最小主应力与煤体的抗拉强度之和时,煤体开始破裂;裂隙总是沿着最大主应力的方向发展.实验模拟结果和理论分析相吻合.
The stress state around water injection hole was analyzed and the crack fracture criterion was calculated according to the theory of elastic mechanics quantitatively. The calculation model about water injection pressure is given when horizontal and vertical cracks appear. The direction of crack propagation and its required pressure is explored. In the laboratory, the critical injection pressure and the direction of crack generation and extention is simulated employing the self-developed simulation device about coal crack generation and extention loaded by the high pressure water. Experimental investigation shows that： coal fracture initiate when pump injection pressure overcome the sum of minimum principal stress and the tensile strength of coal; Fracture is always along the direction of maximum principal stress. The experimental simulation results and theoretical analysis are identical with each other.
出处
《辽宁工程技术大学学报（自然科学版）》
CAS
北大核心
2014年第7期892-897,共6页
Journal of Liaoning Technical University (Natural Science)
基金
河南省重点科技攻关基金资助项目(132102210485)
国家自然科学基金资助项目(51174082)
关键词
裂缝起裂
延展规律
试验装置
水力压裂
泵注压力
fracture crack
extension regularity
experimental device
hydraulic fracturing
pump injection pressure
