Impact fracturing of rock-like material using carbon dioxide under different temperatures and pressures  

作　　者：Shaobin Hu Zhengyong Yan Chun Zhu Manchao He Shuogang Pang 

机构地区：[1]College of Civil and Transportation Engineering,Hohai University,Nanjing,210098,China [2]Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering,Hohai University,Nanjing,210098,China [3]School of Earth Sciences and Engineering,Hohai University,Nanjing,210098,China [4]National Key Laboratory for Disaster Prevention,Control,and Intelligent Construction and Maintenance of Tunnel Engineering,China University of Mining and Technology(Beijing),Beijing,100083,China [5]School of Mechanics and Civil Engineering,China University of Mining and Technology,Beijing,100083,China

出　　处：《Journal of Rock Mechanics and Geotechnical Engineering》2025年第1期370-384,共15页岩石力学与岩土工程学报(英文)

基　　金：supported by“Intergovernmental Cooperation in Science,Technology and Innovation(ISTI)”Key Special Project 2023“Intergovernmental Cooperation Programme between China and the United States”(Grant No.2023YFE0120500);the National Natural Science Foundation of China(Grant No.41702289);the Foundation of Hubei Key Laboratory of Blasting Engineering(Grant No.HKLBEF202004).

摘　　要：Unconventional resources (oil, gas, and geothermal) are often buried deep underground within dense rock strata and complex geological structures, making it increasingly difficult to create volumetric fractures through conventional hydraulic fracturing. This paper introduces a novel method of supercritical energetic fluid thermal shock fracturing. It pioneers a CO_(2) deflagration impact triaxial pneumatic fracturing experimental system, using high-strength similar materials to simulate deep, hard rock masses. The study investigates the rock-breaking process and crack propagation patterns under supercritical CO_(2) thermal shock, revealing and discussing the types of thermal shock-induced fractures, their formation conditions, and discrimination criteria. The research indicates that higher supercritical CO_(2) thermal shock pressures and faster pressure release rates facilitate the formation of radial branching fractures, circumferential cracks, and branch cracks. Typically, CO_(2) thermal shock generates 3–5 radial main cracks, which is significantly more than the single main crack formed by hydraulic fracturing. The formation of branched cracks is often caused by compression-shear failure and occurs under relatively harsh conditions, determined by the confining pressure, rock properties, peak thermal shock pressure, and the pressure sustained post-decompression. The findings are expected to offer a safe, efficient, and controllable shockwave method of supercritical fluid thermal shock fracturing for the exploitation of deep unconventional oil and gas resources.

关 键 词：Cracking mechanism Supercritical CO_(2) True triaxial experimental Impact fracturing 

分 类 号：TU45[建筑科学—岩土工程]