基于DIC顶板导向水力压裂缝网跨界面扩展应变场响应试验研究

作者：Yankun Ma, Hongjie Liu, Aohan Zhao, Daiyuan Ma, Guyu WANG, Xi Zhang · 发表于：Chinese journal of rock mechanics and engineering · 年份：2025 · DOI：10.3724/1000-6915.jrme.2024.0630 · 被引用次数：2 · 研究领域：Rock Mechanics and Modeling、Hydraulic Fracturing and Reservoir Analysis、Coal Properties and Utilization

Roof-guided hydraulic fracturing technology presents significant potential for regional gas drainage in outburst-prone coal seams. To investigate the dynamic cross-interface propagation behavior of fractures, we conducted hydraulic fracturing experiments on “roof rock-coal” composite specimens using a self-developed true triaxial fracturing system equipped with visual observation capabilities. Real-time fracture propagation was monitored through an observation window, while digital image correlation (DIC) was employed to analyze the evolution of the strain field during cross-interface fracture extension. Key findings include: (1) Significant heterogeneous deformation was observed during fracture propagation, with distinct zones of tensile and compressive strain localization flanking the fracture. Fractures predominantly developed within the tensile strain localization zones, with propagation paths closely aligned with the morphology of these zones. (2) The influence ranges of the tensile and compressive strain localization zones measured 532–706 times and 459–481 times the fracture width, respectively. During cross-interface propagation, strain fields exhibited marked disparities across the rock-coal interface, with strain localization zones extending into the adjacent medium as fractures advanced. (3) Propagation rates were notably lower in the roof strata, where fracture-tip tensile strain localization zones were short and wide. Conversely, higher propagation rates were obs...