Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,su...Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes.展开更多
椎间盘由髓核、纤维环和软骨终板组成,对维持脊柱正常生理功能至关重要。椎间盘退变(intervertebral disc degeneration,IDD)是导致腰背痛等脊柱退行性疾病的主要病理基础,给人们的健康状况造成极大的困扰。然而目前对IDD的分子机制仍...椎间盘由髓核、纤维环和软骨终板组成,对维持脊柱正常生理功能至关重要。椎间盘退变(intervertebral disc degeneration,IDD)是导致腰背痛等脊柱退行性疾病的主要病理基础,给人们的健康状况造成极大的困扰。然而目前对IDD的分子机制仍然缺乏清晰的了解,导致缺乏有效的靶向干预措施。RAS同源家族成员A(RAS homolog family member A,RhoA)/Rho相关蛋白激酶(Rho-associated protein kinase,ROCK)信号通路是调节细胞收缩、迁移和生长的经典通路。其被激活后可参与调控细胞骨架重塑、细胞外基质代谢、生物钟节律、细胞表型改变、细胞衰老及死亡等环节,进而影响IDD的病理进程。深入探究RhoA/ROCK信号通路在IDD中的作用,不仅能揭示疾病发生的分子生物学机制,也有望为研发靶向该通路的治疗策略提供理论依据。展开更多
Correction:International Journal of Coal Science&Technology(2025)12:13 https://doi.org/10.1007/s40789-024-00731-8 In this article(Zhang et al.2025),Tables 6,7,8,10,11 and 13 contain errors as described below.
Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These roc...Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These rock masses are predominantly composed of sedimentary,para-metamorphic,and volcanic rock types,characterized by a set of prominent,primary bedding structural planes(layers)exhibiting relatively consistent orientations and significant spatial continuity.展开更多
The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.I...The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.In this regard,we proposed a reliable rating approach for classifying rock masses based on the reliability theory.This theory was incorporated into the RMR system to establish the functions of rock masses of different classifications.By analyzing the probability distribution patterns of various parameters used in the RMR system and using the Monte Carlo method to calculate the reliability probability of surrounding rock belonging to each classifi cation,reliable RMR values for the rock mass to be excavated can be obtained.The results demonstrate that it is feasible to adopt the reliability theory in classifi cation tasks considering the randomness characteristics of rock and soil.As verified through a case study of the Lushan Tunnel project,the proposed approach can be used to obtain the probability of the uncertainty of the calculated RMR values of underground engineering rock masses,and the calculation results are consistent with reality.The proposed approach can serve as a reference for studies in other fi elds and also applies to other rock mass classifi cation methods.展开更多
A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synth...A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems.展开更多
Rock is geometrically and mechanically multiscale in nature,and the traditional phenomenological laws at the macroscale cannot render a quantitative relationship between microscopic damage of rocks and overall rock st...Rock is geometrically and mechanically multiscale in nature,and the traditional phenomenological laws at the macroscale cannot render a quantitative relationship between microscopic damage of rocks and overall rock structural degradation.This may lead to problems in the evaluation of rock structure stability and safe life.Multiscale numerical modeling is regarded as an effective way to gain insight into factors affecting rock properties from a cross-scale view.This study compiles the history of theoretical developments and numerical techniques related to rock multiscale issues according to different modeling architectures,that is,the homogenization theory,the hierarchical approach,and the concurrent approach.For these approaches,their benefits,drawbacks,and application scope are underlined.Despite the considerable attempts that have been made,some key issues still result in multiple challenges.Therefore,this study points out the perspectives of rock multiscale issues so as to provide a research direction for the future.The review results show that,in addition to numerical techniques,for example,high-performance computing,more attention should be paid to the development of an advanced constitutive model with consideration of fine geometrical descriptions of rock to facilitate solutions to multiscale problems in rock mechanics and rock engineering.展开更多
1.Objective The Songliao Basin(SB)is situated on the eastern margin of Eurasia continent(Northeast Asia).During the Late Jurassic to Early Cretaceous,hundreds of rifting basins developed in this area,and the SB is a u...1.Objective The Songliao Basin(SB)is situated on the eastern margin of Eurasia continent(Northeast Asia).During the Late Jurassic to Early Cretaceous,hundreds of rifting basins developed in this area,and the SB is a unique case among them as it evolved into the largest rift basin.The rift basin filling of SB includes Huoshiling Formation,Shahezi Formation,and Yingcheng Formation in ascending order.The mega-rifting was controlled by the Mongol-Okhotsk Collisional Belt to the north and northwest and the Pacific Subduction Zone to the east(Wang PJ et al.,2016).As the first rifting succession,the Huoshiling Formation contains key information about the formation of the rifting basins and records the evolution of the Mongol-Okhotsk Collisional Belt and the Pacific Subduction Zone.However,the geological period of the Huoshiling Formation has not been well constrained for two main reasons.First,it is easily confused with the Yingcheng Formation,as both are dominated by volcanogenic-sedimentary successions.Second,there is lack of reliable dating samples from the uppermost part of the Huoshiling Formation due to its considerable burial depth.展开更多
0 INTRODUCTION Due to the sudden and highly destructive nature of slope rock collapse,developing effective early warning systems has become an urgent challenge in geotechnical engineering(Cai and Detournay,2024;Loew e...0 INTRODUCTION Due to the sudden and highly destructive nature of slope rock collapse,developing effective early warning systems has become an urgent challenge in geotechnical engineering(Cai and Detournay,2024;Loew et al.,2017).Traditional monitoring methods primarily target the acceleration stage preceding disasters(such as displacement monitoring for landslides and debris flows),which is effective for early warning of plastic collapse disasters but often inadequate for brittle failure modes(Walter et al.,2019;Chao et al.,2018;Crosta et al.,2017).展开更多
This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical ...This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(R_(D/G))and vitrinite reflectance(R_(o)).展开更多
Abrasiveness as an intrinsic property of rocks defines the extent of wear or loss when interacting with other materials.In engineering sectors like hard rock mining and tunnelling,comprehending rock abrasiveness holds...Abrasiveness as an intrinsic property of rocks defines the extent of wear or loss when interacting with other materials.In engineering sectors like hard rock mining and tunnelling,comprehending rock abrasiveness holds paramount importance due to its direct effect on tool wear during excavation.Among the diverse methods for assessing rock abrasiveness,the Cerchar abrasivity test emerges as the most widely used approach.Over time,the Cerchar test has garnered substantial attention from scholars,who have delved into the factors influencing test results due to testing conditions and examined the connection between the physical-mechanical parameters of rocks and their abrasiveness.Recent advancements in testing instrument have expanded our ability to measure additional parameters during rock cutting or drilling,yielding fresh insights for abrasiveness assessment,tool wear prediction,tool performance evaluation and rock excavatability estimation.The Cerchar abrasivity test,coupled with recent developments in testing instrument and parameter measurement,holds promising potential for enhancing our comprehension of rock abrasiveness and its practical implications.This review systematically traces the evolution of the test.It commences with an overview of the test origin and progression,emphasizing its pivotal role in assessing rock abrasiveness.Furthermore,it consolidates and categorizes the research contributions from various scholars regarding the test.This includes enhancements and refinements of the testing apparatus,as well as investigations into various testing orientations and their effects on different types of rocks.Moreover,this review illuminates the broader applications and interdisciplinary possibilities of this test,not only in material science but also in tribology.It underscores how the insights gleaned from the Cerchar test can be extrapolated to diverse areas of research beyond the scope of rock engineering.展开更多
Existing creep constitutive models rarely incorporate studies on the coupling mechanism between creep damage and rock strain softening/hardening.This study analyzed the strain softening and hardening behaviors of argi...Existing creep constitutive models rarely incorporate studies on the coupling mechanism between creep damage and rock strain softening/hardening.This study analyzed the strain softening and hardening behaviors of argillaceous sandstone and sandy mudstone during load-induced failure based on the plastic increment theory.These behaviors were then coupled with an improved Burgers creep model to establish a coupled creep-damage and plastic softening/hardening model.Finally,the validity and engineering applicability of the proposed model were verified through FLAC~(3D)numerical simulations.The numerical simulation results of standard cylindrical specimens show that the established coupling model can effectively reflect the unloading creep deformation law and failure characteristics of argillaceous sandstone and sandy mudstone.Taking the diversion tunnel of a hydropower station in Northwest China as an example for engineering application,the coupled creep-damage and plastic softening/hardening model is introduced into FLAC~(3D)to carry out numerical simulation calculation of the tunnel under excavation and unsupported creep conditions.The results show that the uncoordinated deformation of the upper and lower walls of the surrounding rock of the tunnel is more prominent.When the buried depth of the tunnel increases to 80 m,the monitoring point C in the sandy mudstone area of the upper wall shows nonlinear accelerated deformation under unsupported creep conditions,and the maximum displacement in the horizontal direction reaches 44.5 mm,and the maximum displacement in the vertical direction reaches 53.5 mm.The coupled creep-damage and plastic softening/hardening model established in the research results can well describe the whole process of uncoordinated deformation and failure in the unloading creep process of soft-hard interbedded rock mass.展开更多
基金the National Key Research and Development Program of China(Grant No.2023YFC3009400).
文摘Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes.
文摘椎间盘由髓核、纤维环和软骨终板组成,对维持脊柱正常生理功能至关重要。椎间盘退变(intervertebral disc degeneration,IDD)是导致腰背痛等脊柱退行性疾病的主要病理基础,给人们的健康状况造成极大的困扰。然而目前对IDD的分子机制仍然缺乏清晰的了解,导致缺乏有效的靶向干预措施。RAS同源家族成员A(RAS homolog family member A,RhoA)/Rho相关蛋白激酶(Rho-associated protein kinase,ROCK)信号通路是调节细胞收缩、迁移和生长的经典通路。其被激活后可参与调控细胞骨架重塑、细胞外基质代谢、生物钟节律、细胞表型改变、细胞衰老及死亡等环节,进而影响IDD的病理进程。深入探究RhoA/ROCK信号通路在IDD中的作用,不仅能揭示疾病发生的分子生物学机制,也有望为研发靶向该通路的治疗策略提供理论依据。
文摘Correction:International Journal of Coal Science&Technology(2025)12:13 https://doi.org/10.1007/s40789-024-00731-8 In this article(Zhang et al.2025),Tables 6,7,8,10,11 and 13 contain errors as described below.
基金supported by the National Natural Science Foundation of China(Nos.42107211 and U23A20651)the Natural Science Foundation of Sichuan Province(No.2025ZNSFSC0097)。
文摘Layered rock masses represent complex geological formations commonly encountered in the surrounding rock of deep engineering excavations(Hou et al.,2019;Xu et al.,2017;Yang C H et al.,2009;Xian and Tan,1989).These rock masses are predominantly composed of sedimentary,para-metamorphic,and volcanic rock types,characterized by a set of prominent,primary bedding structural planes(layers)exhibiting relatively consistent orientations and significant spatial continuity.
基金supported by the National Natural Science Foundation of China [Grant No.52079077]China Postdoctoral Science Foundation (Grant No. 2022M711962)。
文摘The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.In this regard,we proposed a reliable rating approach for classifying rock masses based on the reliability theory.This theory was incorporated into the RMR system to establish the functions of rock masses of different classifications.By analyzing the probability distribution patterns of various parameters used in the RMR system and using the Monte Carlo method to calculate the reliability probability of surrounding rock belonging to each classifi cation,reliable RMR values for the rock mass to be excavated can be obtained.The results demonstrate that it is feasible to adopt the reliability theory in classifi cation tasks considering the randomness characteristics of rock and soil.As verified through a case study of the Lushan Tunnel project,the proposed approach can be used to obtain the probability of the uncertainty of the calculated RMR values of underground engineering rock masses,and the calculation results are consistent with reality.The proposed approach can serve as a reference for studies in other fi elds and also applies to other rock mass classifi cation methods.
基金supported by grants from the Guangxi Science and Technology Major Project(GKAA24206023)the Biological Breeding-National Science and Technology Major Project(2024ZD04077)+2 种基金the National Natural Science Foundation of China(32272120)the National Key Research and Development Program of China(2024YFF1000800)the Guangdong Basic Research Center of Excellence for Precise Breeding of Future Crops Major Project(FCBRCE-202502,FCBRCE-202504).
文摘A growing global population and the increasing prevalence of diet-related health issues such as“hidden hunger”,obesity,hypertension,and diabetes necessitate a fundamental rethinking of crop design and breeding.Synthetic metabolic engineering offers a method to modify and redesign metabolic pathways to increase the nutritional value of crops.We summarize recent advances in the biofortification of key nutrients including provitamin A,vitamin C,vitamin B9,iron,zinc,anthocyanins,flavonoids,and unsaturated fatty acids.We discuss the potential of multi-gene stacking,gene editing,enzyme engineering,and artificial intelligence in synthetic metabolic engineering.We propose future research directions and potential solutions centered on leveraging AI-driven systems biology,precision gene editing,enzyme engineering,agrobacterium-mediated genotype-independent transformation,and modular metabolic engineering strategies to develop next-generation nutritionally enhanced super crops and transform global food systems.
基金National Natural Science Foundation of China,Grant/Award Numbers:52192691,52192690。
文摘Rock is geometrically and mechanically multiscale in nature,and the traditional phenomenological laws at the macroscale cannot render a quantitative relationship between microscopic damage of rocks and overall rock structural degradation.This may lead to problems in the evaluation of rock structure stability and safe life.Multiscale numerical modeling is regarded as an effective way to gain insight into factors affecting rock properties from a cross-scale view.This study compiles the history of theoretical developments and numerical techniques related to rock multiscale issues according to different modeling architectures,that is,the homogenization theory,the hierarchical approach,and the concurrent approach.For these approaches,their benefits,drawbacks,and application scope are underlined.Despite the considerable attempts that have been made,some key issues still result in multiple challenges.Therefore,this study points out the perspectives of rock multiscale issues so as to provide a research direction for the future.The review results show that,in addition to numerical techniques,for example,high-performance computing,more attention should be paid to the development of an advanced constitutive model with consideration of fine geometrical descriptions of rock to facilitate solutions to multiscale problems in rock mechanics and rock engineering.
基金supported by the National Natural Science Foundation of China(42102135,42072140,42202122 and 41790453)Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-M202101502,KJQN202201549 and KJQN202101535)+1 种基金Natural Science Foundation of Chongqing(CSTB2022NSCQ-JQX0031 and CSTB2022NSCQMSX1586)China Scholarship Council(202208505055)。
文摘1.Objective The Songliao Basin(SB)is situated on the eastern margin of Eurasia continent(Northeast Asia).During the Late Jurassic to Early Cretaceous,hundreds of rifting basins developed in this area,and the SB is a unique case among them as it evolved into the largest rift basin.The rift basin filling of SB includes Huoshiling Formation,Shahezi Formation,and Yingcheng Formation in ascending order.The mega-rifting was controlled by the Mongol-Okhotsk Collisional Belt to the north and northwest and the Pacific Subduction Zone to the east(Wang PJ et al.,2016).As the first rifting succession,the Huoshiling Formation contains key information about the formation of the rifting basins and records the evolution of the Mongol-Okhotsk Collisional Belt and the Pacific Subduction Zone.However,the geological period of the Huoshiling Formation has not been well constrained for two main reasons.First,it is easily confused with the Yingcheng Formation,as both are dominated by volcanogenic-sedimentary successions.Second,there is lack of reliable dating samples from the uppermost part of the Huoshiling Formation due to its considerable burial depth.
基金supported by the National Key R&D Program of China(No.2023YFC3081400)the National Natural Science Foundation of China(No.41702371)+3 种基金the Open Fund Project of State Key Laboratory of Mining Response and Disaster Prevention in Deep Coal Mines(No.SKLMRDPC22KF13)the Supported by State key Laboratory of Mining Disaster Prevention and Control(Shandong University of Science and Technology),Ministry of Education(No.DPEPM202502)the Open Fund Research Project Supported by State Key Laboratory of Strata Intelligent Control and Green Mining Co-founded by Shandong Province and the Ministry of Science and Technology(No.SICGM202503)the Fund of Chongqing Key Laboratory of Facility Damage Mechanism and Protection in Highland Mountain Environment(No.LQ24KFJJ09)。
文摘0 INTRODUCTION Due to the sudden and highly destructive nature of slope rock collapse,developing effective early warning systems has become an urgent challenge in geotechnical engineering(Cai and Detournay,2024;Loew et al.,2017).Traditional monitoring methods primarily target the acceleration stage preceding disasters(such as displacement monitoring for landslides and debris flows),which is effective for early warning of plastic collapse disasters but often inadequate for brittle failure modes(Walter et al.,2019;Chao et al.,2018;Crosta et al.,2017).
基金supported by the National Natural Science Foundation of China(42362022)the Open Fund of the Shaanxi Key Laboratory of Petroleum Accumulation Geology(PAG-202406)the Open Fund of the Mine Geology and Environment Academician and Expert Workstation(2024OITYSZJGZZ-005)。
文摘This study investigated the heterogeneous responses of organic matter(OM)in highly-to over-mature source rocks during thermal maturation.An integrated analysis was conducted on the Raman spectroscopic and geochemical signatures of shales from the Lower Silurian Longmaxi Formation and the Lower Cambrian Qiongzhusi Formation,as well as anthracites from the Lower Permian Shanxi–Formation and the Upper Carboniferous Taiyuan Formation(collectively referred to as the Shanxi Taiyuan Formations).Additionally,burial and thermal evolution modeling was employed to support the analysis.A systematic assessment of Raman spectral parameters(e.g.,the positions and intensity ratio of the D and G bands)revealed robust correlations between the thermal history patterns of source rocks and molecular structural evolution parameters.The subsequent mechanistic quantification demonstrated that the maturation state of the source rocks was subjected to the hierarchical control of three principal factors:Peak heating temperature,the duration of sustained thermal intensity,and effective maturation duration.In addition,comparative analyses demonstrated that the anthracites attained higher structural ordering under sustained thermal conditions.This contrasts with the disordered carbon matrices observed in the intermittently heated shales.Raman spectroscopy further revealed broader variations in the D and G band intensities of the Longmaxi Formation compared to the Qiongzhusi Formation.This difference is associated with their different thermal histories.The thermal burial histories confirm that shales in the Longmaxi Formation underwent thermal exposure at lower peak temperatures over a shorter duration compared to those in the Qiongzhusi Formation.Finally,this study established a maturity calibration model for over-mature source rocks through a systematic correlation between Raman peak height ratios(R_(D/G))and vitrinite reflectance(R_(o)).
文摘Abrasiveness as an intrinsic property of rocks defines the extent of wear or loss when interacting with other materials.In engineering sectors like hard rock mining and tunnelling,comprehending rock abrasiveness holds paramount importance due to its direct effect on tool wear during excavation.Among the diverse methods for assessing rock abrasiveness,the Cerchar abrasivity test emerges as the most widely used approach.Over time,the Cerchar test has garnered substantial attention from scholars,who have delved into the factors influencing test results due to testing conditions and examined the connection between the physical-mechanical parameters of rocks and their abrasiveness.Recent advancements in testing instrument have expanded our ability to measure additional parameters during rock cutting or drilling,yielding fresh insights for abrasiveness assessment,tool wear prediction,tool performance evaluation and rock excavatability estimation.The Cerchar abrasivity test,coupled with recent developments in testing instrument and parameter measurement,holds promising potential for enhancing our comprehension of rock abrasiveness and its practical implications.This review systematically traces the evolution of the test.It commences with an overview of the test origin and progression,emphasizing its pivotal role in assessing rock abrasiveness.Furthermore,it consolidates and categorizes the research contributions from various scholars regarding the test.This includes enhancements and refinements of the testing apparatus,as well as investigations into various testing orientations and their effects on different types of rocks.Moreover,this review illuminates the broader applications and interdisciplinary possibilities of this test,not only in material science but also in tribology.It underscores how the insights gleaned from the Cerchar test can be extrapolated to diverse areas of research beyond the scope of rock engineering.
基金funded by the Natural Science Foundation of China(Grant No.U22A20600)。
文摘Existing creep constitutive models rarely incorporate studies on the coupling mechanism between creep damage and rock strain softening/hardening.This study analyzed the strain softening and hardening behaviors of argillaceous sandstone and sandy mudstone during load-induced failure based on the plastic increment theory.These behaviors were then coupled with an improved Burgers creep model to establish a coupled creep-damage and plastic softening/hardening model.Finally,the validity and engineering applicability of the proposed model were verified through FLAC~(3D)numerical simulations.The numerical simulation results of standard cylindrical specimens show that the established coupling model can effectively reflect the unloading creep deformation law and failure characteristics of argillaceous sandstone and sandy mudstone.Taking the diversion tunnel of a hydropower station in Northwest China as an example for engineering application,the coupled creep-damage and plastic softening/hardening model is introduced into FLAC~(3D)to carry out numerical simulation calculation of the tunnel under excavation and unsupported creep conditions.The results show that the uncoordinated deformation of the upper and lower walls of the surrounding rock of the tunnel is more prominent.When the buried depth of the tunnel increases to 80 m,the monitoring point C in the sandy mudstone area of the upper wall shows nonlinear accelerated deformation under unsupported creep conditions,and the maximum displacement in the horizontal direction reaches 44.5 mm,and the maximum displacement in the vertical direction reaches 53.5 mm.The coupled creep-damage and plastic softening/hardening model established in the research results can well describe the whole process of uncoordinated deformation and failure in the unloading creep process of soft-hard interbedded rock mass.
