西宁地区黄土斜坡稳定性研究——以盐庄—西杏园北侧斜坡为例

Study on stability of loess slope in Xining region——Taking the North slope of the Yanzhuang—Xixingyuan as an example

为快速、准确地判断不同坡高、坡度对黄土斜坡稳定性的影响,服务于实际工程建设,文中以西宁市盐庄—西杏园北侧黄土斜坡为例,通过定性评价与定量评价相结合的方法,综合评价研究区黄土斜坡在不同工况组合下的稳定性。利用理正岩土软件中的边坡稳定分析模块,采用瑞典条分法,搜索最不利滑动面,并进行联合剖面反演,修正黄土的抗剪强度试验指标,按不同工况组合定量计算各段斜坡的稳定系数及剩余下推力,并运用苏联学者洛巴索夫绘制的均质粘性土坡稳定性计算图表,确定不同坡度黄土斜坡的极限稳定坡高,对计算结果进行幂函数曲线拟合,最终导出坡度α和极限坡高H之间的判别方程式为H=1.0×10~6×α^(-2.593 4),结合斜坡体所处的微地貌特征及剩余下推力大小,提出不同的治理方案建议。

In order to quickly and accurately determine the effects of the slope height and slope degree on stability of loess slope,and to serve the construction of practical engineering,taking the north slope of the Yanzhuang-Xixingyuan as an example,the loess slope stability under different operating conditions was evaluated comprehensively by combining qualitative evaluation and quantitative evaluation method. Using slope stability analysis module in Rational Geotechnical Software,the Swedish article points method was adopted to search the most unfavorable sliding surface,and to invert joint profile. The loess shear strength test index was corrected. The slope stability coefficient and residual thrust of each slope were calculated quantitatively according to the combination of different working conditions. The map of homogeneous clay soil slope stability calculation by former Soviet scholar Lobesov was used to determine the limits stable slope height of different loess slope. The calculation results were used for power function curve fitting. The gradient α and limit the discriminant equation between the slope height H,H = 1. 0＊ 10~6＊ α^（-2. 593 4） was derived. The countermeasures were put forward based on micro morphological characteristics of slope body and residual thrust size.