西延高铁黄土高边坡稳定性计算及强度反演分析  

Stability Calculation and Strength Inversion Analysis of High Loess Slope Along the Xi'an-Yan'an HighSpeed Railway

作　　者：赵文辉 ZHAO Wenhui(Shaanxi Railway Engineering Survey Co.,Ltd,Xi’an,Shaanxi 710043)

机构地区：[1]陕西铁道工程勘察有限公司,陕西西安710043

出　　处：《地质与勘探》2024年第5期1054-1065,共12页Geology and Exploration

基　　金：中铁第一勘察设计院集团有限公司科研项目(编号:院科23KY-D006)资助。

摘　　要：西延高铁沿线发育8000余处滑坡及不稳定高边坡,在项目建设过程中,黄土高边坡已成为重大致灾因素之一,因其造成的滑坡、崩塌等易危害路基、桥梁、隧道口、车站等重要构筑物。通过对铜川至延安段的黄土边坡调绘,选取了72处坡高范围为30~90 m的典型黄土高边坡,分区绘制了坡体高度与宽度的拟合方程。基于黄土高边坡稳定性计算方程组,应用Slope/W模块构建断面模型,应用Morgenstern-Price法逐级反演获得极限状态下(稳定系数F_(s)=1.0)高边坡不同坡高对应的综合抗剪强度参数c、φ值。结果表明:边坡高度与粘聚力c成正相关,与内摩擦角φ成负相关,且二者对边坡稳定性的敏感度也不同,低坡时,φ值较高,贡献更加突出;高坡时,c值明显增高,贡献更大。铜黄段与黄延段不同坡高的反演强度参数变化趋势非常相似。但相同坡高范围内,铜黄段的c值普遍高于黄延段15~25 kPa,相对应的φ值低于黄延段1°~5°,这一强度变化规律与黄土在这一区域的成分及其物理性质反映的特点相吻合。并以陕西洛川东咀头滑坡为例,对该反演方法进行了验算,反演获得的抗剪强度参数与实测值较为吻合。More than 8000 landslides and unstable high slopes have developed along the Xi'an-Yan'an high-speed railway.During the project construction process,high loess slopes have become one of the major disaster causing factors.The landslides and collapses caused by them often endanger important structures such as roadbeds,bridges,tunnel entrances,stations and other important structures.By mapping the loess slopes from Tongchuan to Yan'an,72 typical high loess slopes with a height range of 30~90 meters were selected,and the fitting equations for the height and width of the slopes were plotted in different zones.Based on the stability calculation equations for calculating the stability of loess high slopes,the Slope/W module was applied to construct the section model,and the Morgenstern-Price method was applied to invert step by step to obtain the values of the integrated shear strength parameter c andφcorresponding to different slope heights of high slopes under the limit state(stability coefficient F_(s)=1.0).The results show that slope height is positively correlated with cohesion c and negatively correlated with the angle of internal frictionφ.Both have different sensitivities to slope stability,with higher values ofφand more prominent contributions at low slopes,and significantly higher values ofφand greater contributions at high slopes.The trend of the inversion intensity parameters of different slope heights in the Tongchuan-Huangling and HuanglingYan'an sections is very similar,but within the same slope height range,theφvalue of the Tongchuan-Huangling section is generally higher than that of the Huangling-Yan'an section by 15~25 kPa,and the correspondingφvalue is lower than that of the Huangling-Yan'an section by 1°~5°.The above pattern of intensity change is in line with that reflected by the composition of loesses and their physical properties in this region.Finally,taken the Dongzuitou landslide in Luochuan,Shaanxi Province as an example,the inversion method was verified,and the shear strength paramete

关 键 词：黄土高边坡 抗剪强度 极限状态 Slope/W 反演 西延高铁 

分 类 号：U212.22[交通运输工程—道路与铁道工程] P642.13[天文地球—工程地质学]