赵凯凯,姜鹏飞,冯彦军,孙晓冬,程利兴,郑建伟

• 1:煤炭科学研究总院开采研究分院
• 2:煤炭科学研究总院煤炭资源高效开采与洁净利用国家重点实验室
• 3:中煤科工开采研究院有限公司
• 4:天地科技股份有限公司开采设计事业部

摘要(Abstract)：

为研究水力裂纹起裂特征,优化水力压裂设计及施工,采用最大周向拉应力准则作为水力裂纹的开裂判据,推导裂纹起裂角和临界水压的计算方程。分析起裂角和临界水压与预制裂纹倾角、注入水压、应力差和孔隙压力等的关系。研究结果表明:起裂角随预制裂纹倾角的增加呈先增加后减小的趋势;随着水压增高,裂纹起裂角逐渐减小;起裂角随应力差的增加呈单调递增趋势,随孔隙水压增加呈单调递减趋势。临界水压随裂纹倾角的增加呈单调增加的趋势。整体而言,临界水压随应力差增大而增加;随预制裂纹长度的增加而逐渐降低;随断裂韧度的增加呈单调递增趋势;随孔隙水压增加呈单调递减趋势。理论预测的起裂角及临界水压与水力压裂试验结果较为吻合。研究结论可为水力压裂设计及施工提供借鉴。

关键词(KeyWords)： 定向水力压裂;水力裂纹;起裂角;临界水压;最大周向拉应力准则

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金资助项目(51704160);; 天地科技股份有限公司科技创新创业资金专项资助项目(2018-TD-MS027,2019-TD-ZD008)

作者(Author): 赵凯凯,姜鹏飞,冯彦军,孙晓冬,程利兴,郑建伟

DOI: 10.13532/j.jmsce.cn10-1638/td.20201217.001

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