Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rockesoft rockewater interface.Previous studies have not provided a theo...Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rockesoft rockewater interface.Previous studies have not provided a theoretical analysis of the length,inclination angle,and propagation angle of micron-scale cracks,nor have they established appropriate criteria to describe the crack propagation process.The propagation mechanism of micron-scale cracks in red-bed soft rocks under hydraulic action is not yet fully understood,which makes it challenging to prevent engineering disasters in these types of rocks.To address this issue,we have used the existing generalized maximum tangential stress(GMTS)and generalized maximum energy release rate(GMERR)criteria as the basis and introduced parameters related to micron-scale crack propagation and water action.The GMTS and GMERR criteria for micronscale crack propagation in red-bed soft rocks under hydraulic action(abbreviated as the Wmic-GMTS and Wmic-GMERR criteria,respectively)were established to evaluate micron-scale crack propagation in redbed soft rocks under hydraulic action.The influence of the parameters was also described.The process of micron-scale crack propagation under hydraulic action was monitored using uniaxial compression tests(UCTs)based on digital image correlation(DIC)technology.The study analyzed the length,propagation and inclination angles,and mechanical parameters of micron-scale crack propagation to confirm the reliability of the established criteria.The findings suggest that the Wmic-GMTS and Wmic-GMERR criteria are effective in describing the micron-scale crack propagation in red-bed soft rocks under hydraulic action.This study discusses the mechanism of micron-scale crack propagation and its effect on engineering disasters under hydraulic action.It covers topics such as the internal-external weakening of nano-scale particles,lateral propagation of micron-scale cracks,weakening of the mechanical properties of millimeter-scale soft rocks,and resulting interface damage at the engineering scale.The study provides a theoretical basis for the mechanism of disasters in red-bed soft-rock engineering under hydraulic action.展开更多
Deterioration of the physical properties of redbeds is one of the leading causes of geological disasters,engineering problems,and ecological damage.Fabric changes are internal factors leading to the deterioration of p...Deterioration of the physical properties of redbeds is one of the leading causes of geological disasters,engineering problems,and ecological damage.Fabric changes are internal factors leading to the deterioration of physical properties.Existing research on fabric changes in redbeds is qualitative and fuzzy,and their impact on the decline of physical properties needs to be revealed urgently,making the efficient control of redbeds disasters challenging.Therefore,this study focuses on 22 types of redbeds samples and divides them into five classes based on their fabric(composition and structure).Physical property degradation experiments were conducted on different classifications of redbeds during water–rock interaction,and the impact of fabric changes on the degradation of physical properties was analyzed.The results indicate that a linear correlation exists between the internal changes in composition,structure,and physical properties under the action of static water.Moreover,the trend of changes between composition and structure,composition–physical properties,and structure–physical properties shows an exponential regression relationship.Based on this,an action mechanism between compositions such as redbeds,catastrophic minerals,elements,and oxides,as well as the void structure,was proposed,revealing the multifield degradation mechanism of the chemical reactions of the compositions,physical response of the structure,and mechanical reaction of the rock block under the influence of the fabric.The research results can provide a foundation for theoretical research and engineering practice of disaster modes,disaster mechanisms,and prevention and control principles of redbeds disasters.展开更多
基金funded by the National Natural Science Foundation of China(NSFC)(Grant Nos.42293354,42293351,and 42277131).
文摘Micron-scale crack propagation in red-bed soft rocks under hydraulic action is a common cause of engineering disasters due to damage to the hard rockesoft rockewater interface.Previous studies have not provided a theoretical analysis of the length,inclination angle,and propagation angle of micron-scale cracks,nor have they established appropriate criteria to describe the crack propagation process.The propagation mechanism of micron-scale cracks in red-bed soft rocks under hydraulic action is not yet fully understood,which makes it challenging to prevent engineering disasters in these types of rocks.To address this issue,we have used the existing generalized maximum tangential stress(GMTS)and generalized maximum energy release rate(GMERR)criteria as the basis and introduced parameters related to micron-scale crack propagation and water action.The GMTS and GMERR criteria for micronscale crack propagation in red-bed soft rocks under hydraulic action(abbreviated as the Wmic-GMTS and Wmic-GMERR criteria,respectively)were established to evaluate micron-scale crack propagation in redbed soft rocks under hydraulic action.The influence of the parameters was also described.The process of micron-scale crack propagation under hydraulic action was monitored using uniaxial compression tests(UCTs)based on digital image correlation(DIC)technology.The study analyzed the length,propagation and inclination angles,and mechanical parameters of micron-scale crack propagation to confirm the reliability of the established criteria.The findings suggest that the Wmic-GMTS and Wmic-GMERR criteria are effective in describing the micron-scale crack propagation in red-bed soft rocks under hydraulic action.This study discusses the mechanism of micron-scale crack propagation and its effect on engineering disasters under hydraulic action.It covers topics such as the internal-external weakening of nano-scale particles,lateral propagation of micron-scale cracks,weakening of the mechanical properties of millimeter-scale soft rocks,and resulting interface damage at the engineering scale.The study provides a theoretical basis for the mechanism of disasters in red-bed soft-rock engineering under hydraulic action.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Numbers:42293354,42277131,42293351,42293355 and 42293350)。
文摘Deterioration of the physical properties of redbeds is one of the leading causes of geological disasters,engineering problems,and ecological damage.Fabric changes are internal factors leading to the deterioration of physical properties.Existing research on fabric changes in redbeds is qualitative and fuzzy,and their impact on the decline of physical properties needs to be revealed urgently,making the efficient control of redbeds disasters challenging.Therefore,this study focuses on 22 types of redbeds samples and divides them into five classes based on their fabric(composition and structure).Physical property degradation experiments were conducted on different classifications of redbeds during water–rock interaction,and the impact of fabric changes on the degradation of physical properties was analyzed.The results indicate that a linear correlation exists between the internal changes in composition,structure,and physical properties under the action of static water.Moreover,the trend of changes between composition and structure,composition–physical properties,and structure–physical properties shows an exponential regression relationship.Based on this,an action mechanism between compositions such as redbeds,catastrophic minerals,elements,and oxides,as well as the void structure,was proposed,revealing the multifield degradation mechanism of the chemical reactions of the compositions,physical response of the structure,and mechanical reaction of the rock block under the influence of the fabric.The research results can provide a foundation for theoretical research and engineering practice of disaster modes,disaster mechanisms,and prevention and control principles of redbeds disasters.
