Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow.In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loosedeposits ...Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow.In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loosedeposits failure are frequently reported, however adequate measures for reducing debris flow are notavailable practically. In this context, a time-dependent model was established to determine the changesof water table of loose deposits using hydraulic and topographic theories. In addition, the variation inwater table with elapsed time was analyzed. The formulas for calculating hydrodynamic and hydrostaticpressures on each strip and block unit of deposit were proposed, and the slope stability and failure risk ofthe loose deposits were assessed based on the time-dependent hydraulic characteristics of establishedmodel. Finally, the failure mechanism of deposits based on infinite slope theory was illustrated, with anexample, to calculate sliding force, anti-sliding force and residual sliding force applied to each slice. Theresults indicate that failure of gully deposits under the effect of rainfall is the result of continuouslyincreasing hydraulic pressure and water table. The time-dependent characteristics of loose depositfailure are determined by the factors of hydraulic properties, drainage area of interest, rainfall pattern,rainfall duration and intensity.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.41202258)STS Project(Grant No.KFJ-EW-STS-094)+1 种基金Research Plan Project of China Railway Eryuan Engineering Group Co.,Ltd.(Grant No.13164196(13-15))the State Key Laboratory Project Fund of Geohazard Prevention and Geoenvironment Protection(Grant No.SKLGP2013K012)
文摘Failure of loose gully deposits under the effect of rainfall contributes to the potential risk of debris flow.In the past decades, researches on hydraulic mechanism and time-dependent characteristics of loosedeposits failure are frequently reported, however adequate measures for reducing debris flow are notavailable practically. In this context, a time-dependent model was established to determine the changesof water table of loose deposits using hydraulic and topographic theories. In addition, the variation inwater table with elapsed time was analyzed. The formulas for calculating hydrodynamic and hydrostaticpressures on each strip and block unit of deposit were proposed, and the slope stability and failure risk ofthe loose deposits were assessed based on the time-dependent hydraulic characteristics of establishedmodel. Finally, the failure mechanism of deposits based on infinite slope theory was illustrated, with anexample, to calculate sliding force, anti-sliding force and residual sliding force applied to each slice. Theresults indicate that failure of gully deposits under the effect of rainfall is the result of continuouslyincreasing hydraulic pressure and water table. The time-dependent characteristics of loose depositfailure are determined by the factors of hydraulic properties, drainage area of interest, rainfall pattern,rainfall duration and intensity.
