Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the ...Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the seepage properties of disintegrated dolomite within the strata.However,conventional experimental methods are time-consuming and expensive and may not be effective in investigating seepage characteristics due to the heterogeneity of disintegrated dolomite.In this study,pore network model(PNM)was established by the computerized tomography(CT)scanning technology to characterize the pores.Meanwhile,the seepage and coefficient of permeability under different inlet stress conditions based on the accurate pore model were realized by linking the commercial image processing software Avizo with the commercial multi-physics modeling package Comsol.The results show that the porosities of severely and completely disintegrated dolomites are 29.17% and 45.37%,respectively.The grade of pore development increases with disintegration grade,which facilitates seepage failure.Severely and completely disintegrated dolomites have the coefficients of permeability of 9.67×10^(-7) m/s and 1.61×10^(-6) m/s,respectively.Under conventional conditions,severely and completely disintegrated dolomites undergo seepage failure above a pressure difference of 6×10^(3) Pa and 5×10^(3) Pa,respectively.These results are consistent with both in situ water pressure tests in the borehole and laboratory tests with the constant-head method,demonstrating that CT scanning is an effective method for observing fractures and pores in disintegrated dolomite for seepage evaluation.展开更多
Underground debris flows,arising from the complex interplay of anthropogenic activities and rainfall-induced hydromechanical processes,present significant geotechnical hazards that remain poorly understood due to thei...Underground debris flows,arising from the complex interplay of anthropogenic activities and rainfall-induced hydromechanical processes,present significant geotechnical hazards that remain poorly understood due to their hidden nature and dynamic multiphase triggers.Focusing on underground debris flow in a mining area in Southwest China,this study advances an integrated framework combining air-ground transient electromagnetic method(AGTEM)and computational fluid dynamics coupled with the discrete element method(CFD-DEM),revealing the migration mechanism in which microscale multiphase hydraulic erosion drives the macroscopic initiation of underground debris flow.Key findings include:(1)The identification of three transport phases(rapid erosion,slow erosion,and stabilization)provides actionable thresholds for monitoring and mitigation.(2)The coupled feedback between hydraulic conductivity anisotropy and the formation of preferential flow is the primary driver of large-scale debris transportation.(3)Linking mining-induced seismic energy to vibration-induced liquefaction via DEM simulations offers a physics-based explanation for flow mobilization triggers.The integrated geophysical-numerical framework offers new capabilities for predicting initiation thresholds and developing physics-based mitigation strategies in mining-affected terrains.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.42162026)the Basic Research Program in Yunnan Province,China(Grant No.202401AT070328)the Young Talents Project of“Xingdian Talent Support Program"in Yunnan Province,China(Grant No.YNWR-QNBJ-2020-019).
文摘Disintegrated dolomite slope and tunnel disasters occur frequently due to poor water stability of disintegrated dolomite,primarily in a form of seepage failure.For engineering purposes,it is critical to determine the seepage properties of disintegrated dolomite within the strata.However,conventional experimental methods are time-consuming and expensive and may not be effective in investigating seepage characteristics due to the heterogeneity of disintegrated dolomite.In this study,pore network model(PNM)was established by the computerized tomography(CT)scanning technology to characterize the pores.Meanwhile,the seepage and coefficient of permeability under different inlet stress conditions based on the accurate pore model were realized by linking the commercial image processing software Avizo with the commercial multi-physics modeling package Comsol.The results show that the porosities of severely and completely disintegrated dolomites are 29.17% and 45.37%,respectively.The grade of pore development increases with disintegration grade,which facilitates seepage failure.Severely and completely disintegrated dolomites have the coefficients of permeability of 9.67×10^(-7) m/s and 1.61×10^(-6) m/s,respectively.Under conventional conditions,severely and completely disintegrated dolomites undergo seepage failure above a pressure difference of 6×10^(3) Pa and 5×10^(3) Pa,respectively.These results are consistent with both in situ water pressure tests in the borehole and laboratory tests with the constant-head method,demonstrating that CT scanning is an effective method for observing fractures and pores in disintegrated dolomite for seepage evaluation.
基金support from the National Natural Science Foundation of China(Grant Nos.42377170 and 42407212)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(Grant No.GZB20230606)+1 种基金the Postdoctoral Research Foundation of China(Grant No.2024M752679)the Sichuan Natural Science Foundation(Grant No.2025ZNSFSC1205).
文摘Underground debris flows,arising from the complex interplay of anthropogenic activities and rainfall-induced hydromechanical processes,present significant geotechnical hazards that remain poorly understood due to their hidden nature and dynamic multiphase triggers.Focusing on underground debris flow in a mining area in Southwest China,this study advances an integrated framework combining air-ground transient electromagnetic method(AGTEM)and computational fluid dynamics coupled with the discrete element method(CFD-DEM),revealing the migration mechanism in which microscale multiphase hydraulic erosion drives the macroscopic initiation of underground debris flow.Key findings include:(1)The identification of three transport phases(rapid erosion,slow erosion,and stabilization)provides actionable thresholds for monitoring and mitigation.(2)The coupled feedback between hydraulic conductivity anisotropy and the formation of preferential flow is the primary driver of large-scale debris transportation.(3)Linking mining-induced seismic energy to vibration-induced liquefaction via DEM simulations offers a physics-based explanation for flow mobilization triggers.The integrated geophysical-numerical framework offers new capabilities for predicting initiation thresholds and developing physics-based mitigation strategies in mining-affected terrains.
