水力压裂后,当微裂缝闭合时初始损伤带的诱导应力导致围岩应力重新分布.为确定初次压裂后应力分布规律,将围岩区域分为破坏区、损伤区和弹性区,建立了基于损伤理论的人工裂缝诱导应力模型,选择吉林油田1口生产井为研究对象,计算结果表明:人工裂缝诱导应力随井筒的距离的增大而逐渐减小,计算结果与实际情况吻合较好.
The induced stress of initial damage zone results in the redistribution of surrounding rock stress when the micro-crack closes after hydraulic fracture.The surrounding rock zone was divided into broken zone,damage zone and elastic range to determine the stress distribution law after primary fracturing.Model of artificial fracture induced stress was built based on the damage theory.A produced well in Jilin Oilfield was taken as an example.The results show that artificial fracture induced stress decreases with the distance increased.The result was consistent with practice.