几何参数和强度参数对边坡三维稳定性的影响
来源期刊:中南大学学报(自然科学版)2013年第4期
论文作者:宋维胜 李江腾
文章页码:1634 - 1638
关键词:边坡;稳定性;安全系数;滑动面;三维效应;宽高比
Key words:slope; stability; factor of safety; slip surface; three-dimensional effect; ratio of width to height
摘 要:利用FLAC3D软件建立边坡的三维数值模型,分别改变边坡宽高比、边坡角、岩土体内摩擦角和黏结力,采用强度折减法计算边坡安全系数。研究结果表明:随着宽高比W/H的增大,边坡安全系数明显减小,并趋于一定值;当W/H>6,边坡问题可简化为平面应变问题;宽高比越小,边坡的三维效应越突出;当W/H<3时,边坡三维的效应不能忽视;当坡角越小时,在相同宽高比下,稳定系数偏差越大,即边坡的三维效应越明显;随着内摩擦角的增大,边坡的三维效应逐渐减弱,且边坡滑动由深层滑动转变为浅层滑动;边坡三维效应随着黏结力的增大而增大,边坡滑动由浅层滑动转变为深层滑动,滑动面越来越缓。
Abstract: The three-dimensional numerical model of slope was founded by FLAC3D software, changing the ratio of width to height W/H, slope angle, friction angle and cohesion of geotechnical material to calculate the factor of safety of slope by the strength reduction method. The results show that with the increase of W/H, the factor of safety of slope decreases obviously to a constant value. If W/H>6, the slope problem can be simplified to plane strain problem. With the decrease of the ratio of width to height, the three-dimensional effect of slope is more obvious, if W/H<3, the three-dimensional effect of slope cannot be neglected. Under the same W/H, the differences between three-dimensional results and two-dimensional results are larger with lower slope angle, indicating the more obvious three-dimensional effect of slope. With the increase of friction angle, the three-dimensional effect of slope gradually becomes smaller, and the failure mode of slope changes from deep slipping to shallow slipping. With the increase of cohesion, the three-dimensional effect of slope becomes more obvious, and the failure mode of slope changes from shallow slipping mode to the deep slipping mode, inclination of slip suface becomes slower.
宋维胜1,李江腾2
(1. 湖南张家界市水利局,湖南 张家界,427000;2. 中南大学 资源与安全工程学院,湖南 长沙,410083)
摘 要:利用FLAC3D软件建立边坡的三维数值模型,分别改变边坡宽高比、边坡角、岩土体内摩擦角和黏结力,采用强度折减法计算边坡安全系数。研究结果表明:随着宽高比W/H的增大,边坡安全系数明显减小,并趋于一定值;当W/H>6,边坡问题可简化为平面应变问题;宽高比越小,边坡的三维效应越突出;当W/H<3时,边坡三维的效应不能忽视;当坡角越小时,在相同宽高比下,稳定系数偏差越大,即边坡的三维效应越明显;随着内摩擦角的增大,边坡的三维效应逐渐减弱,且边坡滑动由深层滑动转变为浅层滑动;边坡三维效应随着黏结力的增大而增大,边坡滑动由浅层滑动转变为深层滑动,滑动面越来越缓。
关键词:边坡;稳定性;安全系数;滑动面;三维效应;宽高比
SONG Weisheng1, LI Jiangteng2
(1. Zhangjiajie Water Conservancy Bureau, Zhangjiajie 427000, China;2. School of Resources and Safety Engineering, Central South University, Changsha 410083, China)
Abstract:The three-dimensional numerical model of slope was founded by FLAC3D software, changing the ratio of width to height W/H, slope angle, friction angle and cohesion of geotechnical material to calculate the factor of safety of slope by the strength reduction method. The results show that with the increase of W/H, the factor of safety of slope decreases obviously to a constant value. If W/H>6, the slope problem can be simplified to plane strain problem. With the decrease of the ratio of width to height, the three-dimensional effect of slope is more obvious, if W/H<3, the three-dimensional effect of slope cannot be neglected. Under the same W/H, the differences between three-dimensional results and two-dimensional results are larger with lower slope angle, indicating the more obvious three-dimensional effect of slope. With the increase of friction angle, the three-dimensional effect of slope gradually becomes smaller, and the failure mode of slope changes from deep slipping to shallow slipping. With the increase of cohesion, the three-dimensional effect of slope becomes more obvious, and the failure mode of slope changes from shallow slipping mode to the deep slipping mode, inclination of slip suface becomes slower.
Key words:slope; stability; factor of safety; slip surface; three-dimensional effect; ratio of width to height