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
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.
