土坡稳定分析Spencer法的有效应力形式
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摘要
Spencer法是广泛应用的土坡稳定分析方法,原文采用总应力形式,用孔隙水压力系数计算渗流场内各点水压力,间接计算土体有效应力。因浸润线以下土条内水重与土条左侧面、右侧面、底面水压力合成为渗流力,土体受力分为两部分:一部分是土体的浮重及侧面有效土压力,另一部分是水体作用的渗流力。基于此重新分析土条受力,沿用Spencer原文推导方法建立有效应力形式的力平衡和力矩平衡表达式,求解有效应力形式的安全系数,形成土坡稳定分析Spencer法的有效应力形式。根据均质各向同性土坡渗流场中流线分布呈坡顶、坡面和坡底近似多段式折线的简化形式,对Spencer原文中的两个经典算例进行验证计算,并对另一算例应用SLOPE/W进行验证计算,计算结果显示:提出的Spencer法有效应力形式所得边坡稳定安全系数值与原文总应力形式计算结果相近。建立的Spencer法的有效应力形式为边坡稳定分析提供一种评价方法。
Spencer method is widely used for soil slope stability analysis. In the original paper,total stress method was applied for mathematic derivation. The effective stress of soil was calculated indirectly from water pressure which related to pore-pressure ratio. The resultant of water weight in the soil slice under the phreatic line and pore-water pressure acted on each side of soil slice was seepage force. Forces acted on soil body under phreatic line could be separated into effective from soil skeleton and buoyancy from pore water. The forces acting upon soil slice were reanalyzed. Two equations of equilibrium in respect of effective forces and effective moments were founded. The safety factor of the effective force form could be obtained and the effective stress form of Spencer method for slope stability analysis could be formed. For seepage flow field of homogeneous isotropic soil slope,the streamline could be divided into three or more straight lines parallelling slope crest,slope surface and slope base respectively. Two cases in Spencer's original paper and another case were studied by the new method. The results showed that the effective stress form of Spencer method for soil slope stability analysis was validated.
Spencer method is widely used for soil slope stability analysis. In the original paper,total stress method was applied for mathematic derivation. The effective stress of soil was calculated indirectly from water pressure which related to pore-pressure ratio. The resultant of water weight in the soil slice under the phreatic line and pore-water pressure acted on each side of soil slice was seepage force. Forces acted on soil body under phreatic line could be separated into effective from soil skeleton and buoyancy from pore water. The forces acting upon soil slice were reanalyzed. Two equations of equilibrium in respect of effective forces and effective moments were founded. The safety factor of the effective force form could be obtained and the effective stress form of Spencer method for slope stability analysis could be formed. For seepage flow field of homogeneous isotropic soil slope,the streamline could be divided into three or more straight lines parallelling slope crest,slope surface and slope base respectively. Two cases in Spencer's original paper and another case were studied by the new method. The results showed that the effective stress form of Spencer method for soil slope stability analysis was validated.
引文
[1] SPENCER E. A Method of Analysis of the Stability of Embankments Assuming Parallel Interslice Forces[J].Geotechnique,1967,17(1):11-26.
[2] DUNCAN J M,WRIGHT S G,Brandon T L. Soil Strength and Slope Stability[M]. Hoboken,New Jersey:John Wiley&Sons Inc.,2014.
[3]矢田部龍一,榎明潔,八木則男.降雨浸透を考慮した斜面安定解析法の検討[J]. Journal of Japan Landslide Society,1986,22(4):1-7.
[4]古谷保.極限平衡法を利用した斜面安定解析:Spencer法と他方法との比較[G]∥農業土木学会論文集第120号.東京:農業林学会,1985.
[5]古谷保.定常浸透状態における水中重量法と一般分割法の計算式[J]. Journal of Japan Landslide Society,1996,33(1):9-14.
[6]古谷保.Spencerの一般分割法についての考察[J]. Journal of Japan Landslide Society,1997,34(2):35-41.
[7] GeoSlope International Ltd. Stability Modeling with SLOPE/W:An Engineering Methodology[M]. Alberta, Canada:Geo Slope International Ltd.,2012.
[8]中国地质环境监测院.长江三峡工程库区滑坡防治工程设计与施工技术规程[M].北京:地质出版社,2000.
[9]中华人民共和国国土资源部.滑坡防治工程设计与施工技术规范:DZ/T 0219—2006[S].北京:中国标准出版社,2006.
[10]杨建民,张丹蕾,秦军.考虑渗流作用的土坡稳定分析Fellenius法和简化Bishop法[J].工业建筑,2017,47(12):111-120.
[11]孟凡宪.土坡稳定分析Spencer方法的一种有效应力形式[D].天津:天津大学,2015.
[12]薛禹群.地下水动力学[M].北京:地质出版社,1997.
[13]张蔚榛.地下水与土壤水动力学[M].北京:中国水利水电出版社,1996.
[14]陈崇希,林敏.地下水动力学[M].武汉:中国地质大学出版社,1999.
[15] MORRISON I M,GREENWOOD J R. Assumptions in Simplified Slope Stability Analysis by the Method of Slice[J]. Geotechnique,1989,39(3):503-509.
[16] LAMBE T W,WHITMAN R V. Soil Mechanics[M]. New York:Wiley,1969.
[17] ZHU D Y,LEE C F,QIAN Q H,et al. A Concise Algorithm for Computing the Factor of Safety Using the Morgenstern-Price Method[J]. Canadian Geotechnical Journal,2005,42(1):272-278.
[2] DUNCAN J M,WRIGHT S G,Brandon T L. Soil Strength and Slope Stability[M]. Hoboken,New Jersey:John Wiley&Sons Inc.,2014.
[3]矢田部龍一,榎明潔,八木則男.降雨浸透を考慮した斜面安定解析法の検討[J]. Journal of Japan Landslide Society,1986,22(4):1-7.
[4]古谷保.極限平衡法を利用した斜面安定解析:Spencer法と他方法との比較[G]∥農業土木学会論文集第120号.東京:農業林学会,1985.
[5]古谷保.定常浸透状態における水中重量法と一般分割法の計算式[J]. Journal of Japan Landslide Society,1996,33(1):9-14.
[6]古谷保.Spencerの一般分割法についての考察[J]. Journal of Japan Landslide Society,1997,34(2):35-41.
[7] GeoSlope International Ltd. Stability Modeling with SLOPE/W:An Engineering Methodology[M]. Alberta, Canada:Geo Slope International Ltd.,2012.
[8]中国地质环境监测院.长江三峡工程库区滑坡防治工程设计与施工技术规程[M].北京:地质出版社,2000.
[9]中华人民共和国国土资源部.滑坡防治工程设计与施工技术规范:DZ/T 0219—2006[S].北京:中国标准出版社,2006.
[10]杨建民,张丹蕾,秦军.考虑渗流作用的土坡稳定分析Fellenius法和简化Bishop法[J].工业建筑,2017,47(12):111-120.
[11]孟凡宪.土坡稳定分析Spencer方法的一种有效应力形式[D].天津:天津大学,2015.
[12]薛禹群.地下水动力学[M].北京:地质出版社,1997.
[13]张蔚榛.地下水与土壤水动力学[M].北京:中国水利水电出版社,1996.
[14]陈崇希,林敏.地下水动力学[M].武汉:中国地质大学出版社,1999.
[15] MORRISON I M,GREENWOOD J R. Assumptions in Simplified Slope Stability Analysis by the Method of Slice[J]. Geotechnique,1989,39(3):503-509.
[16] LAMBE T W,WHITMAN R V. Soil Mechanics[M]. New York:Wiley,1969.
[17] ZHU D Y,LEE C F,QIAN Q H,et al. A Concise Algorithm for Computing the Factor of Safety Using the Morgenstern-Price Method[J]. Canadian Geotechnical Journal,2005,42(1):272-278.