四川省达宣公路老林村滑坡稳定性评价及防治措施研究

发布时间：2018-04-16 06:45

本文选题：达宣公路 + 老林村滑坡　；参考：《成都理工大学》2015年硕士论文

【摘要】：滑坡是山区公路建设中的主要地质灾害之一。四川省达宣公路K6+460-K6+760m处老林村滑坡局部出现较明显的变形迹象,拟建达宣公路在滑坡体中下部通过。局部的填方将对滑坡产生一定影响,所以本项研究对公路路基安全和工程施工及公路的运行安全具有重要意义。本文在通过对老林村滑坡的现场调查基础上,收集相关资料,对该滑坡的特征及形成机制开展系统的研究,通过定性的方法分析滑坡稳定性及路堤填筑后滑坡破坏模式及稳定性,同时采用定量的方法计算天然工况、暴雨工况下滑坡稳定性及局部稳定性,运用GEO-STUDIO数值分析软件对滑坡天然工况及路堤填筑工况下应力应变变化及暴雨工况下滑坡体渗流场进行数值模拟分析。在上述研究基础上,针对滑坡稳定性状况及变形特征提出具体防治措施,进行防治工程的设计,主要获得以下认识及成果:(1)老林村滑坡为发育于红层砂泥岩地层中的大型缓倾顺层老滑坡,平面上整体呈舌形,平均厚度12m,约230×104m3,滑体以块碎石土为主,滑带为粉质粘土,滑床为侏罗系中统新田沟组杂色砂岩、水云母页岩,滑面呈直线型,滑坡形成机制为斜坡受构造与坡体卸荷作用影响,同时斜坡中泥岩软弱夹层在前缘河谷下切侵蚀过程中被切穿揭露、软化,以不利的岩土结构组合为不良地质基础,以“滑移-拉裂”破坏模式沿软弱层向临空面滑移破坏。(2)滑坡整体未出现明显变形现象,滑坡形成后表现出分区变形特征(1#变形区、2#变形区)。自然状态下滑坡整体及1#变形区、2#变形区处于稳定状态,降雨工况下滑坡整体处于基本稳定状态,1#变形区、2#变形区处于欠稳定状态。(3)在滑坡前部填方后,1#变形区、2#变形区不受填方影响,稳定性状态为改变,滑坡整体处于基本稳定状态,填方段及以下处于欠稳定状态,降雨条件下滑坡整体处于基本稳定状态,路堤及以下为不稳定状态。(4)针对老林村滑坡特征及填方后滑坡稳定性状态,进行了防治措施研究,针对滑坡的特征采用地表排水+抗滑桩支挡相结合的治理方案,在滑坡后缘外设置截水沟,滑坡两侧设置排水沟,在填筑路堤前缘设置抗滑桩。
[Abstract]:Landslide is one of the main geological disasters in mountain highway construction.There are obvious signs of local deformation of Laolin Village landslide at K6 460-K6 760m of Daxuan Highway in Sichuan Province, and it is proposed to build Daxuan Highway through the middle and lower part of the landslide body.The partial fill will affect the landslide to some extent, so this study is of great significance to the safety of highway subgrade, construction and operation of highway.On the basis of field investigation of Laolin village landslide, this paper collects relevant data, and carries out systematic research on the characteristics and formation mechanism of the landslide.Through qualitative analysis of landslide stability and landslide failure mode and stability after embankment filling, quantitative method is used to calculate landslide stability and local stability under rainstorm conditions.The stress and strain variation of landslide under natural condition and embankment filling condition and seepage field of landslide body under rainstorm condition were simulated by GEO-STUDIO software.On the basis of the above research, according to the stability condition and deformation characteristics of landslide, the concrete prevention measures are put forward, and the design of the prevention and control project is carried out.The main results are as follows: (1) Laolin Village landslide is a large slowly inclined old landslide in the sand and mudstone strata of Yu Hong layer, with an average thickness of 12 m, with an average thickness of 230 脳 10 4 m 3. The landslide is dominated by macadam and the slip zone is silty clay.The slip bed is the mixed color sandstone of Xintiangou formation of the Middle Jurassic, the hydromica shale, the slippery surface is linear, and the landslide formation mechanism is influenced by the structure and the unloading of the slope body.At the same time, the mudstone weak intercalation in the slope is cut through and exposed during the cutting erosion process of the leading valley, and the bad geological foundation is the unfavorable rock and soil structure combination.According to the failure mode of "slipping-tension crack", there is no obvious deformation phenomenon in the whole landslide along the weak layer to the face of the goaf. After the formation of the landslide, the deformation characteristics of the landslide are shown in the zonal deformation zone and the deformation zone is the same as the one in the 2# deformation area.Under the natural condition, the whole landslide and the deformation area of 1# deformation area are in stable state.Under rainfall conditions, the whole landslide is in a basic stable state. The deformation area of the deformation area is in an unstable state. (3) after filling the front part of the landslide, the deformation area of the deformation area is not affected by the fill, but the stability state is changed.The whole landslide is in a basic stable state, the fill section and below are in an unstable state, and the whole landslide is in a basic stable state under the condition of rainfall.According to the characteristics of the landslide in Laolin Village and the stability of the landslide after filling, the prevention and control measures are studied, and the treatment scheme of the surface drainage anti-slide pile supporting and retaining is adopted in view of the characteristics of the landslide.At the back edge of the landslide, there are intercepting gullies, drainage ditches on both sides of the landslide, and anti-slide piles on the front edge of the embankment.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U418.55

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