应土木工程与力学学院、西部灾害与环境力学教育部重点实验室潘春林副教授邀请，美国国家能源技术实验室（NETL）陆冠艺博士于2019年4月25-27日来我校进行学术交流并做学术报告，欢迎广大师生参加。
报告题目：Time-dependent Hydraulic Fracture Initiation and Propagation under subcritical conditions
报告时间： 2019年04月26日（星期五） 14：30-16：00
报告地点：祁连堂322学术报告厅
报告人简介：
Dr. Guanyi Lu is currently an ORISE postdoctoral fellow in the Carbon Storage field work group of National Energy Technology Laboratory in Morgantown, WV, USA. Prior to joining NETL, he received his Ph.D. in Civil Engineering from University of Pittsburgh in 2018 and a B.E. in Civil Engineering from Tongji University. His research is focused on the laboratory and numerical study on the behavior of rocks subjected to subcritical loading conditions and its application in multi-stage hydraulic fracturing stimulation, geological storage of carbon dioxide, and structural health monitoring, etc.
报告摘要：
Multi-stage hydraulic fracturing (HF) is an effective and still emerging technology for completion of horizontal wells in unconventional hydrocarbon reservoirs, and garnering increased attention. In conventional HF stimulations, time-dependence is not typically considered as a factor, while it is shown in laboratory experiments to play a pivotal role in the initiation and the subsequent propagation of hydraulic fracture(s). This talk will discuss the time-dependence of single/multiple hydraulic fracture(s) under subcritical wellbore conditions. Firstly, the laboratory HF experiments show that time-dependent HF initiation under subcritical conditions exists in various rocks. Then A numerical model is developed to capture such delayed initiation of hydraulic fracture. The agreement between the experimental results and numerical prediction confirm the origin of time-dependence of the initiation process on subcritical crack growth and highlight the need to accurately account for the crack growth before it reaches the critical point. After establishing growth of a single hydraulic fracture, this model is extended to the case of simultaneous growth of multiple hydraulic fractures. This model is then used in a parametric study to investigate the competition between the effect of stress shadowing – the suppression of some hydraulic fractures due to the elevated compressive stresses induced by their neighbor(s) - and subcritical crack propagation.