长沙理工大学学报（自然科学版）2024，Vol.21Issue(4)：91-102,12.DOI:10.19951/j.cnki.1672-9331.20230927001
CO2相变冲击下岩石损伤演化规律研究
Research on evolution law of rock damage under CO2 phase change impact
摘要
Abstract
[Purposes]CO2 phase change fracturing technology has the advantages of environmental protection,low risk,and easy control,and it is widely used in mineral mining,engineering construction,and other fields.Exploring the evolution law of CO2 phase change fracturing-induced damage is of great significance for the selection of blasting construction parameters.[Methods]In response to the limitations of the damage model of equivalent explosives to describe CO2 phase change rock breaking process,the ideal gas state equation was used to describe the supercritical CO2 phase change process.Combined with the Mises criterion,a calculation model for rock damage radius under phase change was given.Based on LS-DYNA software,a rock damage calculation model under phase change was established,and the evolution law of rock damage under phase change was analyzed.Furthermore,the influence of parameters such as the fracturing pressure and the type of fracturing tube on the evolution of rock damage was analyzed.[Findings]The established model for calculating the rock damage radius under phase change can effectively evaluate the damage range of rocks.Phase change impact causes radial cracks in the rock,and CO2 phase change gas is embedded in the cracks near the main crack.The crack tip effect promotes the formation of denser circumferential cracks and smaller axial cracks in the rock mass.According to numerical simulations,the range of crack zones generated by the type 85 fracturing tube is 0.42,0.43,and 0.46 m,respectively,under fracturing pressures of 174,250,and 290 MPa.The increase amplitude of crack length slows down with the increase in pipe diameter.The average length of cracks generated by the three types of fracturing tubes including type 51,type 85,and type 100 under a fracturing pressure of 290 MPa is 13.2％,5.75％,and 1.41％higher than that under 174 MPa,respectively.When the fracturing pressure is 250 MPa,the range of crack zones generated by the three types of fracturing tubes is 0.42,0.43,and 0.47 m,respectively.Under the three fracturing pressures,the average crack length generated by the type 100 fracturing tube increases by 14.2％,11.1％,and 2.4％compared to that generated by the type 51 fracturing tube.In addition,with the increase in the fracturing pressure and the diameter of the fracturing tube,the main and circumferential cracks generated by phase change fracturing increase,and the average crack length of the rock increases.[Conclusions]The results can provide a reference for damage control and technical parameter selection in CO2 phase change fracturing construction.关键词
CO2相变致裂/等当量炸药/损伤半径/影响因素/裂隙尺寸Key words
CO2 phase change fracturing/equivalent explosive/damage radius/influencing factor/crack size分类
矿业与冶金引用本文复制引用
李浩田,阿比尔的,贺林林,蒲运杰,刘明维,韩亚峰..CO2相变冲击下岩石损伤演化规律研究[J].长沙理工大学学报（自然科学版）,2024,21(4):91-102,12.基金项目
国家自然科学基金青年基金项目(41907261、42302332) （41907261、42302332）
重庆市自然科学基金资助项目(CSTB2023NSCQ-MSX0913、CSTB2022NSCQ-BHX0738) （CSTB2023NSCQ-MSX0913、CSTB2022NSCQ-BHX0738）
重庆交通大学研究生科研创新项目(2022S0023) Projects(41907261,42302332)supported by the National Natural Science Foundation Youth Fund （2022S0023）
Projects(CSTB2023NSCQ-MSX0913,CSTB2022NSCQ-BHX0738)supported by Chongqing Natural Science Foundation （CSTB2023NSCQ-MSX0913,CSTB2022NSCQ-BHX0738）
Project(2022S0023)supported by Chongqing Jiao tong University Graduate Research Innovation （2022S0023）
