摘要
针对水力压裂作用下裂隙在含有界面层的层状岩体中的扩展问题,开展了实验和数值模拟研究.通过制作砂岩和泥岩的相似材料构成的层状岩石模拟试件,采用数字图像相关方法观测裂隙在含界面层岩石试件中的扩展路径,并运用数值模拟方法模拟裂隙在水力压裂作用下的扩展路径,研究水力压裂作用下裂隙在层状岩体内的扩展规律.研究表明:裂隙在层状岩体内由界面层一侧向另一侧岩体扩展过程中,裂隙尖端沿界面层发生一定迁移后进入另一侧岩体,裂隙在界面层另一侧岩体内的扩展范围大于含预制裂隙一侧的岩体,当界面层另一侧的岩体强度低于含预制裂隙一侧的岩体时,裂隙扩展范围增大;预制裂隙尖端到界面层的距离对裂隙在界面层两侧岩体的扩展影响不明显.
According to the characteristics of crack extension in the stratified rock under the force of hydraulic fracturing,experimental research and numerical simulation were carried out.The analogue stratified rock specimens made of sandstone and mudstone analogue materials are utilized,the crack and interface layer was prepared in specimens, the crack propagation path in the stratified rock was observed by digital image correlation method and numerical simulation method respectively.The results shows that：the crack tip moved along the interface while the crack goes through the interface layer,the range of crack extension on the other side of interface layer is greater than the rock with preset crack,when strength of the rock on the other side of the interface layer is less than the rock with preset crack,crack extension scope enlarges accordingly;the distance from the preset crack tip to interface layer has not the obvious effect on the crack propagation in the stratified rock.So,it can be concluded that the interface layer and the strength difference of rock between the interface layers have effect on the crack propagation path and crack propagation scope in stratified rock.
出处
《地球物理学进展》
CSCD
北大核心
2014年第5期2370-2375,共6页
Progress in Geophysics
基金
国家自然科学基金项目(41002075
51004023)
国家重点基础研究发展计划(973)项目(2010CB226803)联合资助
关键词
天然气开采
裂隙扩展
水力压裂
数字图像相关方法
界面层
界面滑脱
natural gas extraction
crack propagation
hydraulic fracturing
digital image correlation method
interface layer
interface slip
