个人信息Personal Information
教授
博士生导师
硕士生导师
主要任职:President of international exchange committee of the Chinese Society of Rock Mechanics and Engineering CSRME
其他任职:国际岩石力学与岩石工程学会(ISRM)中国国家小组副主席
性别:男
毕业院校:东北大学
学位:博士
所在单位:土木工程系
办公地点:综合实验四号楼330
联系方式:tca@mail.neu.edu.cn
Numerical Modeling of Pore Pressure Influence on Fracture Evolution in Brittle Heterogeneous Rocks
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论文类型:期刊论文
发表时间:2013-09-01
发表刊物:ROCK MECHANICS AND ROCK ENGINEERING
收录刊物:SCIE、EI、Scopus
卷号:46
期号:5
页面范围:1165-1182
ISSN号:0723-2632
关键字:Pore pressure magnitude; Pore pressure gradient; Heterogeneity; Hydraulic fractures; Numerical simulation
摘要:Rock is a heterogeneous geological material. When rock is subjected to internal hydraulic pressure and external mechanical loading, the fluid flow properties will be altered by closing, opening, or other interaction of pre-existing weaknesses or by induced new fractures. Meanwhile, the pore pressure can influence the fracture behavior on both a local and global scale. A finite element model that can consider the coupled effects of seepage, damage and stress field in heterogeneous rock is described. First, two series of numerical tests in relatively homogeneous and heterogeneous rocks were performed to investigate the influence of pore pressure magnitude and gradient on initiation and propagation of tensile fractures. Second, to examine the initiation of hydraulic fractures and their subsequent propagation, a series of numerical simulations of the behavior of two injection holes inside a saturated rock mass are carried out. The rock is subjected to different initial in situ stress ratios and to an internal injection (pore) pressure at the two injection holes. Numerically, simulated results indicate that tensile fracture is strongly influenced by both pore pressure magnitude and pore pressure gradient. In addition, the heterogeneity of rock, the initial in situ stress ratio (K), the distance between two injection holes, and the difference of the pore pressure in the two injection holes all play important roles in the initiation and propagation of hydraulic fractures. At relatively close spacing and when the two principal stresses are of similar magnitude, the proximity of adjacent injection holes can cause fracturing to occur in a direction perpendicular to the maximum principal stress.