煤储层水力压裂裂隙沿井孔起裂扩展的影响因素实验研究  

Test Research on Influence Factors for Cracks Extension of Hydraulic Fracturing Along Borehole in Coal Reservoir

作　　者：李志伟[1] 郤保平[1,2] 郭庆华[1] 田俊斌[1] 郑晓琛[1] 

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]太原理工大学采矿工艺研究所,山西太原030024

出　　处：《矿业研究与开发》2015年第3期13-15,共3页Mining Research and Development

基　　金：山西省高等学校科技资助项目(20111004);山西省青年科学基金项目(2011021023-2)

摘　　要：采用真三轴试验系统和声发射测试系统,对煤块进行水力压裂试验,描述煤块压裂过程中裂隙的发生发展,并对煤块压裂裂隙进行分析研究。得出以下结论:从破裂后裂隙形态看出,裂隙均沿近似最小主应力的方向发生,与理论分析和数值模拟的结果基本相符;煤块本身的层理等原生裂隙对水力压裂裂隙扩展有着显著的诱导作用,成功诱导裂隙沿近似层理方向延伸,达到了实验的预期;由试件压裂过程中声发射监测到的信息,得出试件压裂过程中的撞击-时间曲线,可为煤层气井的压裂提供实验参考。The hydraulic fracturing tests were conducted on coal lump by tri-axial test system and acoustic emission test system.Occurrence and development of cracks in fracturing process were described,and the fracturing cracks were analyzed.The results were obtained as follows.Firstly,from the cracks form after fracturing,it can be seen that the cracks always occurred along the direction of the minimum principal stress,which was basically same to the results of theoretical analysis and numerical simulation.Secondly,the native cracks of coal lump,like the bedding,had obvious inducing effect on cracks extension of hydraulic fracturing,so as to induce cracks extending along the approximate bedding direction, which achieved the experiment expectation.Thirdly,according to the information getting from acoustic emission monitoring during the specimens fracturing,the curve of collision and time was obtained,which provided experimental reference for fracturing of gas well in coal reservoir.

关 键 词：水力压裂 真三轴试验 声发射 裂隙形态 

分 类 号：TE377[石油与天然气工程—油气田开发工程]