中文摘要：

在页岩气开采的水力压裂过程中,套损时有发生,严重影响页岩气开采效率。明确套损机理及其影响因素有助于有针对性地采取缓解措施,避免套损。鉴于此,分析了压裂过程中储层的变形特征,同时综合考虑微地震数据和套损规律等信息,指出压裂施工中套损的主要机理是储层滑移引起的套管剪切。建立了水平井尺度的套损有限元模型,其中利用虚拟热膨胀模拟注液后压裂改造区的体积增加效应,采用单元埋入技术模拟套管和地层之间的相互作用。分析结果表明：天然裂缝长度和倾角对套损有较大影响,但增加套管壁厚不能缓解套损。研究成果对认识和缓解压裂中的套损有一定的理论指导意义。

英文摘要：

Casing failure occurs frequently during the hydraulic fracturing process of shale gas formation,which seriously influences the shale gas recovery efficiency. Defining the mechanism of casing failure and its influencing factors are helpful for mitigation measures and avoiding casing failure. In view of this,the deformation of reservoir during hydraulic fracturing has been analyzed. Combined the knowledge of microseismic data and casing failure rule,it is pointed out that the main mechanism of casing failure during fracturing is casing shear caused by formation slippage. A finite element model of the casing failure in horizontal wells has been established,in which the volume expansion effect of the stimulated zone was simulated by virtual thermal expansion,and the interaction between the casing and the formation was simulated by the unit embedment technique. The results show that the natural fracture length and dip angle have great influence on the casing failure,and the increase of casing wall thickness could not reduce casing failure. The study results could provide certain theoretical guidance in understanding and mitigating casing failure in hydraulic fracturing.