边坡倾倒稳定分析Goodman-Bray法:改进、测试与应用

Improvement,Testing and Application on Goodman-Bray Method for Stability Analysis of Toppling Slope

为确认改进的边坡倾倒稳定分析Goodman-Bray法的正确性和实用性,对改进的边坡倾倒稳定分析Goodman-Bray法进行了深层次的分析、测试及试设计。以柳树沟Ⅰ区变形边坡、龙滩水电站左岸泄水建筑物进口高边坡、天生桥二级水电站厂房南边坡为典型算例,分别讨论了岩块不同宽度、地下水影响与预应力锚索加固等因素对边坡稳定性的影响,最后对正在建设中的两河口水电站泄水建筑物倾倒边坡的稳定性进行了分析。结果表明:当条块宽度越小时安全系数也相应减小;边坡内外水位平衡时,充水并不会对倾倒边坡的稳定产生实质性影响,且坡外水位骤降会导致倾倒边坡的稳定安全系数急剧下降;锚固作用下安全系数有明显提高。考核的成果表明,相应成果合理,改进Goodman-Bray方法可以在工程设计过程中不断改善,日趋成熟。

In order to confirm the feasibility and applicability of the improved Goodman-Bray method for slope toppling analysis, the in-depth analyses, test and design of the improved method was conducted. The effects of different column width, ground water level and prestress reinforcement of anchors on the slope stability was discussed respectively, based on a number of engineering cases including slopes in the first district of Liushugou, intake high slopes of the release structure at the left bank of Longtan Hydropower Station, slopes in the south of Tianshengqiao No. 2 Hydropower Station. The analyses were conducted on the stability of the topping slope of the release structure at Lianghekou Hydropower Station under construction. The results show that, firstly, the safety factor decreases with the decrease of the column width.Secondly, when water level of inside and outside slope tends to stabilize, the filling of reservoir water has no substantial influence on the stability of the slope. The safety factor of the topping slope dramatically decreases with the rapid drawdown of the outside slope. The application of anchors greatly contributes to the increase of factor of safety. The feasibility of the improved Goodman-Bray method can be further improved in the process of the future design.