V型沟谷巨粒土高填方路基修筑技术研究

发布时间：2018-01-03 23:19

本文关键词：V型沟谷巨粒土高填方路基修筑技术研究　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：山区公路常常需要频繁跨越V型沟谷,沟谷地形复杂,修筑运营过程中存在高填路堤整体沉降、局部沉降或边坡失稳等诸多病害,严重影响沟谷高填路基的质量和运营安全。巨粒土填料往往来源于隧道渣料,具有颗粒级配复杂和变异性大等特点,填料的工程特性会对路基稳定及变形产生较大影响。通常情况下,填土路基中填料(即土)的工程性质主要受粒径大于2mm的粗颗粒、带黏性的细颗粒及无黏性的粉粒含量的影响。因此,提高V型沟谷地带巨粒土高填路基的稳定性已成为山区公路建设亟待解决的问题。本论文以雁楠公路巨粒土高填方路基工程项目为依托,对以巨粒土为主的隧道渣料作为筑路材料的V型沟谷超高路堤+支挡结构路基的设计与修筑技术展开研究。第一,通过对巨粒土渣料的物理力学特性的研究,分析不同含水量和不同压实度下强度指标的变化规律,评价巨粒土隧道渣料作为路基填料的适应性和可行性。第二,提出了板桩挡墙强脚和C25片石砼锚杆抗滑挡墙强脚两种设计方案,并利用有限元方法,对两种方案的变形和稳定性进行计算。对比分析最终选板桩挡墙强脚设计方案建立二维平面弹塑性模型,对路堤特征断面沟谷斜坡填料与地面的结合模式、压实度、格宾网对路堤稳定及变形的影响进行分析。第三,建立三维有限元模型,分析不同填筑高度和不同压实度条件下V型沟谷超高路堤的沉降和稳定性的变化规律,得到V型沟谷超高填方+支挡结构路基的沉降变形、侧向位移发生及发展规律和土压力的大小。研究结果表明V型沟谷超高路堤三维沉降值、三维稳定系数与二维值相比,更加符合V型沟谷超高路堤的三维边界效应及实际工程应用,有利于正确评价沟谷超高路堤的沉降和稳定性。第四,在对加筋格宾挡墙的组成、特点、设计理论进行分析总结的基础上,结合实际工程采用有限元数值模拟分析不同尺寸格宾网加筋格宾挡土墙稳定性及变形,并对格宾挡土墙耐久性进行了分析。第五,提出隧道渣料作为筑路材料进行V型沟谷超高填方+支挡结构路基的施工方案和技术措施。路堤采用分层填筑分层碾压并采用经验法、沉降差法控制填筑压实质量,借助水平位移基准网和垂直位移基准网对高路堤进行监测,路堤表面水平及垂向位移量均较小,内部各点受力无明显变化,路堤处于基本稳定状态。
[Abstract]:Mountain highway often needs to cross V-type valley frequently. The terrain of valley is complex. There are many diseases such as overall settlement of high fill embankment local settlement or slope instability in the course of construction and operation. The quality and operation safety of high filling subgrade in gully and valley are seriously affected. The giant grained soil fillers often come from tunnel slag and have the characteristics of complex particle gradation and high variability. The engineering characteristics of fillers have a great influence on the stability and deformation of subgrade. Usually, the engineering properties of fillers in subgrade are mainly affected by coarse particles larger than 2mm in diameter. The effect of the content of fine and non-viscous particles. To improve the stability of high-fill subgrade in V-type gully zone has become the urgent problem of highway construction in mountainous area. This paper relies on the project of high-filling roadbed of Yannan highway. In this paper, the design and construction technology of the subgrade with the V-shaped gully super-high embankment supported by the tunnel slag as the road construction material is studied. Firstly, the physical and mechanical properties of the mega grained soil slag are studied. Analyze the change law of strength index under different water content and different compaction degree, evaluate the adaptability and feasibility of giant granular soil tunnel slag as subgrade filler. Two design schemes of strong foot of plate pile retaining wall and C25 flake concrete anchor are put forward, and the finite element method is used. The deformation and stability of the two schemes are calculated. Finally, a two-dimensional elastic-plastic model is established by comparing and analyzing the design scheme of the strong foot of the plate selection pile retaining wall, and the combination model between the filling and the ground of the embankment with the characteristic section of the gully slope is proposed. Compaction degree and the effect of Gabin net on stability and deformation of embankment are analyzed. Thirdly, three-dimensional finite element model is established. The variation law of settlement and stability of V type gully super-high embankment under different filling height and different compaction degree is analyzed, and the settlement deformation of V type gully super-high fill embankment is obtained. The occurrence and development of lateral displacement and the magnitude of earth pressure. The results show that the three dimensional settlement value and the three dimensional stability coefficient are compared with the two dimensional values. It is more in line with the three-dimensional boundary effect of V-type gully super-high embankment and its practical engineering application, which is conducive to the correct evaluation of settlement and stability of the super-high gully embankment. 4th, the composition and characteristics of reinforced Gabin retaining wall. Based on the analysis and summary of the design theory, the finite element numerical simulation is used to analyze the stability and deformation of the reinforced gribbin retaining wall with different sizes. The durability of GB retaining wall is analyzed. 5th. The construction scheme and technical measures of V-type gully super-high fill embankment with tunnel slag as road construction material are put forward. The embankment is compacted by layered filling and stratified compaction and empirical method is adopted. The settlement difference method controls the filling compaction quality and monitors the high embankment with the help of the horizontal displacement reference network and the vertical displacement reference network. The horizontal and vertical displacement of the embankment surface is smaller and the internal stress does not change obviously. The embankment is basically stable.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U416.1

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