摘要
水力压裂体积张开度是指水力作用引起的单位体积岩石内部张开体积大小,包括孔隙体积张开度和裂缝体积张开度,是进行水力压裂效果预测和评价的重要指标。为了建立孔隙–裂缝融合一体的水力压裂体积张开度模型,提出一个三阶段水力压裂体积张开演化过程模型,利用孔隙弹性力学理论和黏聚断裂损伤演化模型,建立三阶段的体积张开度演化表达式。通过将裂缝体积张开度与经典平行板裂缝张开宽度的演化规律进行匹配拟合,将断裂传播机制对裂缝张开度的影响纳入到体积张开度模型。该模型在孔裂隙的弹性张开网络中引入平行板裂缝,实现经典平行板裂缝理论与孔隙弹性理论的有机融合。作为实例,阐明在4种极限断裂传播机制下,如何利用该模型对水力压裂张开度进行评价和预测。
The hydraulic fracturing volumetric opening,which is defined as the volumetric opening in a per unit bulk volume of rocks,including pore volumetric opening and fracture volumetric opening,is an important reference in assessment of hydraulic fracturing effects. In order to establish a volumetric opening model combining the pore volumetric opening and fracture volumetric opening,in this study,a three staged evolving process model is proposed. Based on which,and using the theory of poroelasticity and a cohesive damage evolution model,a three staged expression of hydraulic volumetric openings is established. By matching the evolving law of fracture volumetric opening with the evolving law of the hydraulic fracture aperture,the fracture propagation regimes are incorporated into the hydraulic volumetric models. The main contribution of this volumetric opening model is bridging the gap between the two classic theories,poroelasticity and hydraulic fracturing propagation,by incorporating the parallel-plates-fracture into the hydraulic opening networks of micro cracks and pores. As examples,assessment of hydraulic fracturing volumetric openings in four limiting propagation regimes,are performed.
作者
王利
孟兵兵
曹运兴
刘晓
WANG Li;MENG Bingbing;CAO Yunxing;LIU Xiao(School of Civil Engineering,Henan Polytechnic University,Jiaozuo,Henan 454003,China;School of Resources and Environmenty Henan Polytechnic University,Jiaozuo,Henan 454003,China;School of Energy Science and Engineerings Henan Polytechnic University,Jiaozuo,Henan 454003,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2020年第5期887-900,共14页
Chinese Journal of Rock Mechanics and Engineering
基金
国家十三五重大专项(2016ZX05067006-002,2017ZX05064002)
河南省高等学校重点科研项目(14A410004)。
关键词
岩石力学
水力压裂
张开度
孔隙弹性
黏聚性断裂
断裂机制
rock mechanics
hydraulic fracture
aperture
poroelasticity
cohesive breakdown
fracture regime