摘要
在边坡稳定性分析中,滑面搜索方法对于得到边坡的稳定性系数至关重要。现今两种常用的边坡稳定性分析方法,极限平衡法以及强度折减法,可以得到极限应力状态下边坡的潜在滑面。而为了评价边坡在当前应力场下的稳定性,提出一种基于聚类分析概念的滑面搜索方法。这种方法综合考虑了边坡各点的位移以及点安全系数,采用K均值聚类法将具有相近性质的点进行分类,把边坡体分为潜在危险区以及稳定区。潜在危险区的边界即为边坡在当前应力状态下的潜在滑面,并运用矢量和方法计算得到其稳定性系数。采用上述方法对3个算例进行验算,并与极限平衡法以及强度折减法进行对比。结果表明:(1)基于聚类分析的边坡稳定性评价方法具有较好的合理性和可靠性;(2)当边坡处于临界状态附近,通过聚类分析得到的潜在滑面与其他两种方法得到的滑面基本一致;当边坡处于较稳定状态时,当前应力状态下的潜在滑面要比强度折减法得到的滑动带范围要更深更广,但求出的稳定性系数也较高;当存在软弱夹层时,矢量和计算出的滑面更为陡峻,稳定性系数比其他两种方法的结果要小。
Study on searching methods of slip surface plays a crucial role in slope stability analysis to assess the safety factor of slopes. The potential failure surface under ultimate stress state can be found by limit equilibrium method（LEM） and strength reduction method（SRM）. The objective of this paper is to present a new slip surface searching method, which considers the distribution of local safety factor and displacement under current stress state. The statistical concept, K-means clustering, is introduced to distinguish the points with similar characters in slope into potential failure set and stable set. Then the boundary of the potential failure set is regarded as the potential slip surface under current stress state and the safety factor of potential slip surface is calculated using vector sum method（VSM）. Afterward, three examples were calculated using the presented method to compare with results from LEM and SRM. Results show that 1） Slope stability evaluation by clustering analysis has been proved to be reliable and effective; 2） If the slope is near the limit state, the potential surface obtained from the proposed method is consistent with the slip surfaces obtained from LEM and SRM. If the slope is stable, the potential slip surface under current stress state is deeper and larger but is with higher safety factor. If there is a weak layer in the slope, the potential slip surface is steeper, and the safety factor calculated from VSM is lower than that calculated from LEM and SRM.
作者
秦雨樵
汤华
冯振洋
尹小涛
王东英
QIN Yu-qiao;TANG Hua;FENG Zhen-yang;YIN Xiao-tao;WANG Dong-ying(State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei 430071,China;University of Chinese Academy of Sciences,Beijing 100000,China;School of Civil Engineering,Chongqing University,Chongqing 400030,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2018年第8期2977-2983,2990,共8页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51608518
No.41202226)
云南省交通科技项目(云交科教[2016]163号一(三))~~
关键词
边坡稳定性分析
滑面搜索方法
聚类分析
矢量和方法
slope stability analysis
slip surface search
clustering analysis
vector sum method
作者简介
秦雨樵，男，1993年生，硕士，主要从事工程岩体稳定性分析方面的研究工作。Email： qinyuqiao_whrsm@163.com
