岩土力学
巖土力學
암토역학
ROCK AND SOIL MECHANICS
2014年
2期
519-528
,共10页
空间评价%位移速率比%滑坡%地理信息系统
空間評價%位移速率比%滑坡%地理信息繫統
공간평개%위이속솔비%활파%지리신식계통
spatial evaluation%displacement speed ratio(DSR)%landslide%geographic information system (GIS)
实测数据表明,松散土质斜坡和具有时效变形特征的岩质斜坡的滑坡变形往往具有蠕变特点,即从开始出现变形到最终失稳破坏一般需经历初始变形、等速变形和加速变形3个阶段。基于典型的滑坡累积位移-时间曲线特征,提出了采用位移速率比作为通用指标来判定滑坡上各点变形阶段的方法:多个连续时段均为等速变形即相邻位移速率比位于0~2之间时,认为进入等速变形阶段;当位移速率比大于2时,初步认为,其进入加速变形阶段。结合典型实例建立了位移速率比判定滑坡上各点变形阶段的判定标准:在滑坡位移速率比大于2之后,滑坡体进入加速变形阶段,对加速变形阶段可再作进一步细分:位移速率比为2~6时,为滑坡体的初加速阶段,为6~8时,滑坡体进入中加速阶段,大于8则为临滑阶段。基于地理信息系统(Geographic information system,简称GIS)平台,建立了滑坡变形空间评价的位移速率比方法,并对金坪子滑坡的空间变形状态进行了评价,验证了该方法的可行性和合理性。
實測數據錶明,鬆散土質斜坡和具有時效變形特徵的巖質斜坡的滑坡變形往往具有蠕變特點,即從開始齣現變形到最終失穩破壞一般需經歷初始變形、等速變形和加速變形3箇階段。基于典型的滑坡纍積位移-時間麯線特徵,提齣瞭採用位移速率比作為通用指標來判定滑坡上各點變形階段的方法:多箇連續時段均為等速變形即相鄰位移速率比位于0~2之間時,認為進入等速變形階段;噹位移速率比大于2時,初步認為,其進入加速變形階段。結閤典型實例建立瞭位移速率比判定滑坡上各點變形階段的判定標準:在滑坡位移速率比大于2之後,滑坡體進入加速變形階段,對加速變形階段可再作進一步細分:位移速率比為2~6時,為滑坡體的初加速階段,為6~8時,滑坡體進入中加速階段,大于8則為臨滑階段。基于地理信息繫統(Geographic information system,簡稱GIS)平檯,建立瞭滑坡變形空間評價的位移速率比方法,併對金坪子滑坡的空間變形狀態進行瞭評價,驗證瞭該方法的可行性和閤理性。
실측수거표명,송산토질사파화구유시효변형특정적암질사파적활파변형왕왕구유연변특점,즉종개시출현변형도최종실은파배일반수경력초시변형、등속변형화가속변형3개계단。기우전형적활파루적위이-시간곡선특정,제출료채용위이속솔비작위통용지표래판정활파상각점변형계단적방법:다개련속시단균위등속변형즉상린위이속솔비위우0~2지간시,인위진입등속변형계단;당위이속솔비대우2시,초보인위,기진입가속변형계단。결합전형실례건립료위이속솔비판정활파상각점변형계단적판정표준:재활파위이속솔비대우2지후,활파체진입가속변형계단,대가속변형계단가재작진일보세분:위이속솔비위2~6시,위활파체적초가속계단,위6~8시,활파체진입중가속계단,대우8칙위림활계단。기우지리신식계통(Geographic information system,간칭GIS)평태,건립료활파변형공간평개적위이속솔비방법,병대금평자활파적공간변형상태진행료평개,험증료해방법적가행성화합이성。
Monitoring data show that the soil landslide or the rock landslide with the aging deformation characteristics, often have creep characteristics;namely it generally undergoes three stages from the beginning to the failure:the initial deformation, the constant speed deformation and the accelerated deformation. Based on the characteristics of typical accumulation displacement-time curve of the landslide, a method has been proposed to determine the different deformation stages of each point of the landslide mass. Taking the displacement speed ratio (DSR) as a general indicator, when DSR 0-2 means the constant speed deformation, and greater than 2 means the accelerated deformation. Based on some typical landslide cases, a displacement over-acceleration criterion has been established to determine the different deformation stages of each point of the sliding mass:DSR=2-6 means the initial acceleration stage; DSR=6-8 means the intermediate acceleration stage; DSR greater than 8 means the pre-slippery stage. A geographic information system (GIS) based method of DSR has been proposed for the spatial stability evaluation of landslides. As an example, the method has been used to determine the spatial deformation state of Jinpingzi landslide; the result verifies its feasibility and reasonability.