人民黄河
人民黃河
인민황하
Yellow River
2013年
11期
76-78
,共3页
孙博%彭宁波%陆继财%王逢睿%肖碧
孫博%彭寧波%陸繼財%王逢睿%肖碧
손박%팽저파%륙계재%왕봉예%초벽
降雨%黄土边坡%稳定性%数值模拟
降雨%黃土邊坡%穩定性%數值模擬
강우%황토변파%은정성%수치모의
rainfall%loess slope%stability%numerical analysis
降雨是影响边坡稳定性的重要因素,雨水入渗使土体饱和度增大、含水量增加、抗剪强度下降,当降雨强度和持续时间超过临界值时,便导致边坡失稳。结合兰州某滑坡治理工程,根据降雨强度和持续时间计算边坡浅层土体在不同时刻的含水量,运用非饱和土抗剪强度理论,对降雨条件下的黄土边坡的稳定性进行了分析。结果表明:持续降雨条件下边坡的变形破坏主要是边坡土体含水量增加引起的;把含水量作为抗剪强度的主要控制指标,建立边坡土体的黏聚力和内摩擦角与降雨持续时间的关系,进行有限元模拟分析,得到边坡安全系数,可为持续降雨条件下黄土边坡的防护和失稳预测提供参考;传统的有限元强度折减法得到的安全系数不能准确反映边坡稳定性的强弱,只能说明边坡是否破坏。
降雨是影響邊坡穩定性的重要因素,雨水入滲使土體飽和度增大、含水量增加、抗剪彊度下降,噹降雨彊度和持續時間超過臨界值時,便導緻邊坡失穩。結閤蘭州某滑坡治理工程,根據降雨彊度和持續時間計算邊坡淺層土體在不同時刻的含水量,運用非飽和土抗剪彊度理論,對降雨條件下的黃土邊坡的穩定性進行瞭分析。結果錶明:持續降雨條件下邊坡的變形破壞主要是邊坡土體含水量增加引起的;把含水量作為抗剪彊度的主要控製指標,建立邊坡土體的黏聚力和內摩抆角與降雨持續時間的關繫,進行有限元模擬分析,得到邊坡安全繫數,可為持續降雨條件下黃土邊坡的防護和失穩預測提供參攷;傳統的有限元彊度摺減法得到的安全繫數不能準確反映邊坡穩定性的彊弱,隻能說明邊坡是否破壞。
강우시영향변파은정성적중요인소,우수입삼사토체포화도증대、함수량증가、항전강도하강,당강우강도화지속시간초과림계치시,편도치변파실은。결합란주모활파치리공정,근거강우강도화지속시간계산변파천층토체재불동시각적함수량,운용비포화토항전강도이론,대강우조건하적황토변파적은정성진행료분석。결과표명:지속강우조건하변파적변형파배주요시변파토체함수량증가인기적;파함수량작위항전강도적주요공제지표,건립변파토체적점취력화내마찰각여강우지속시간적관계,진행유한원모의분석,득도변파안전계수,가위지속강우조건하황토변파적방호화실은예측제공삼고;전통적유한원강도절감법득도적안전계수불능준학반영변파은정성적강약,지능설명변파시부파배。
Rainfall is an important factor influencing slope stability,rain infiltration makes the soil saturation increase and increase of soil moisture and the decrease of shear strength when the rainfall intensity and duration exceed a certain degree,leading to slope instability. Combining with the landslide of Lanzhou Forest of Steles treatment engineering,according to rainfall intensity and duration of that of the shallow stratum of the slope was obtained water content changes,using the unsaturated soil shear strength theory,combined with finite element the shear strength reduction of rain-fall,under the conditions of the loess slope stability was analyzed and the slope instability was forecasted. The results show that a)under the condi-tions of continuous rain,slope deformation and destruction are the main body of increased water content of the slope;b)as the water content to be the main control parameters of the shear strength,set up the slope soil total cohesion,internal friction angle and sustained rainfall time relationship, with the finite element analysis,get the time of slope destruction,can get for continuous rainfall condition of soil slope reinforcement protection and instability forecast to provide the reference;c)the safety coefficient got by traditional FEM strength reduction method in slope stability analysis can-not get exactly the effects of the stability of the slope strength and it can only explain whether the slope is damaged.