水利学报
水利學報
수리학보
2015年
7期
773-782
,共10页
蒋中明%伍忠才%冯树荣%钟辉亚%王江营%王桂尧
蔣中明%伍忠纔%馮樹榮%鐘輝亞%王江營%王桂堯
장중명%오충재%풍수영%종휘아%왕강영%왕계요
边坡稳定性分析%降雨入渗%暂态饱和区%暂态水压力
邊坡穩定性分析%降雨入滲%暫態飽和區%暫態水壓力
변파은정성분석%강우입삼%잠태포화구%잠태수압력
slope stability analysis%rainfall infiltration%transient saturated area%transient water pressure
降雨入渗导致边坡表层出现暂态饱和区并形成暂态水压力。为了研究暂态水压力对边坡稳定性的影响,通过文献研究,总结归纳了边坡暂态饱和区存在形态类型及暂态水压力分布特点,并定义了暂态水压力分布比例系数。基于费伦纽斯条分法,改进了条分假定,提出了考虑条块侧向已知水荷载影响的安全系数计算方法,推导了边坡潜在滑动面位于暂态饱和区与非饱和区两种情形下的安全系数计算公式,编写并验证了可以考虑暂态水压力影响的边坡稳定性分析程序,并进行算例分析。研究表明:边坡安全系数随暂态饱和区厚度的增大而减小,超过一定深度后安全系数将基本维持不变;暂态饱和区厚度相同条件下,暂态水压力分布系数越大边坡安全系数越小;随着暂态饱和区厚度增加,边坡最不利潜在滑动面位置深度呈现减小→增加→减小→增加的变化规律;由于忽略了条间荷载影响,传统费伦纽斯条分法安全系数计算值偏大。
降雨入滲導緻邊坡錶層齣現暫態飽和區併形成暫態水壓力。為瞭研究暫態水壓力對邊坡穩定性的影響,通過文獻研究,總結歸納瞭邊坡暫態飽和區存在形態類型及暫態水壓力分佈特點,併定義瞭暫態水壓力分佈比例繫數。基于費倫紐斯條分法,改進瞭條分假定,提齣瞭攷慮條塊側嚮已知水荷載影響的安全繫數計算方法,推導瞭邊坡潛在滑動麵位于暫態飽和區與非飽和區兩種情形下的安全繫數計算公式,編寫併驗證瞭可以攷慮暫態水壓力影響的邊坡穩定性分析程序,併進行算例分析。研究錶明:邊坡安全繫數隨暫態飽和區厚度的增大而減小,超過一定深度後安全繫數將基本維持不變;暫態飽和區厚度相同條件下,暫態水壓力分佈繫數越大邊坡安全繫數越小;隨著暫態飽和區厚度增加,邊坡最不利潛在滑動麵位置深度呈現減小→增加→減小→增加的變化規律;由于忽略瞭條間荷載影響,傳統費倫紐斯條分法安全繫數計算值偏大。
강우입삼도치변파표층출현잠태포화구병형성잠태수압력。위료연구잠태수압력대변파은정성적영향,통과문헌연구,총결귀납료변파잠태포화구존재형태류형급잠태수압력분포특점,병정의료잠태수압력분포비례계수。기우비륜뉴사조분법,개진료조분가정,제출료고필조괴측향이지수하재영향적안전계수계산방법,추도료변파잠재활동면위우잠태포화구여비포화구량충정형하적안전계수계산공식,편사병험증료가이고필잠태수압력영향적변파은정성분석정서,병진행산례분석。연구표명:변파안전계수수잠태포화구후도적증대이감소,초과일정심도후안전계수장기본유지불변;잠태포화구후도상동조건하,잠태수압력분포계수월대변파안전계수월소;수착잠태포화구후도증가,변파최불리잠재활동면위치심도정현감소→증가→감소→증가적변화규률;유우홀략료조간하재영향,전통비륜뉴사조분법안전계수계산치편대。
Rainfall infiltration leads to the generation of transient saturated area and forming transient water pressure in a slope. For investigation of the influence of transient water pressure on the slope stability, the distribution of transient saturated area and transient water pressure in the slope under the rainfall condi?tions were analyzed based on the literature research. A coefficient for the description of the transient water pressure distribution is also defined. Assumptions of Fellenius slices method were improved, and the meth?od for safety factor calculation with consideration of water pressure acting on the lateral side of the slice is proposed. Furthermore, formulae for calculation of the safety factor of a slope with transient water pressure were deduced in the cases of potential sliding surface in transient saturated area and unsaturated area. A routine for the slope stability analysis based on above suggested formulae was programmed and calculated re?sults of examples were given to illustrate the valid of the programmed routines by the authors. It shows that the safety factor of a slope decreases with the increase of transient saturated area thickness and trends to be a constant after the thickness of transient saturated area reaches some value. The safety factor of a slope with transient saturated area will also decrease with the increase of coefficient of transient water pres?sure distribution in the case of the thickness of transient saturated area keeping the same. The location the potential sliding surface also changes with the variation of transient saturated area thickness and appears a law of decrease, increase, decrease and increase again. Due to neglect of the influence of lateral water pressure on the slice safety factor, the safety factor calculated by the traditional Fellenius slices method is larger than that of improved method proposed in this paper.