【作者】 刘兆生；

【导师】 姚令侃；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2011， 硕士

【摘要】 土工合成材料加筋路堤在地震荷载下的计算分析是一个非常复杂的问题,涉及到填料、加筋材料、路堤类型、填料与加筋的相互作用等等。加筋格宾挡墙更是国内新近才开始研究并在工程现场运用的新型结构,对于挡墙的动力特性及作用机理的研究都非常有限。本文利用岩土专用软件Geo-Studio结合工程现场对相关一般路堤及加筋格宾挡墙进行了拟静力及有限元动力分析,提出了一般路堤的加筋优化方法及加筋格宾挡墙的作用机理、动力特性,为加筋路堤和加筋格宾挡墙的施工及推广提供参考。本文主要研究内容和结论有：(1)通过拟静力法研究发现,汽车荷载对路堤在地震荷载下的整体稳定性影响不大。4米-20米的标准路堤在九度地震荷载下濒临危险状态,需要加强措施,在七度、八度地震荷载作用下,标准路堤基本能保持稳定。放坡及设置平台能有效地提高路堤整体的抗震稳定性,特别是对于高路堤,设置平台能将长大边坡转换成几个一般边坡,有效的减小危险滑坡的滑动范围,提高路堤边坡的整体稳定性。路堤加筋对于提高路堤整体稳定性及减少路堤在地震作用下的位移,都具有重要的作用,是提高路堤抗震稳定性的有效手段。(2)提出一般加筋路堤优化方案,一般经过放坡及设置平台的路堤,路堤顶部至上部第一级平台处是最危险的部位,需要重点加强,对于不同高度的路堤,可根据情况在中上部适当以短筋加强。具体来说,对于低于20m的标准路堤及斜坡路堤,一般在顶部至上部第一个平台间满铺土工格栅,上部适当铺设短筋即可；对于20m-30m的标准路堤及斜坡路堤,在顶部至第一个平台间满铺土工格栅,上部按0.5-1m的间隔铺设短筋即可。(3)加筋格宾挡墙具有良好的抗震性能,尤其对于大震,效果明显。挡墙在地震荷载作用下,顶部动土压力值最大,底部次之,中间最小,顶部和中部的加速度放大系数较底部的大。格宾挡墙在大震作用下其破坏形式为顶部的拉裂及撞击变形破坏,加筋格宾挡墙后0.45H(H为墙高)至墙顶的范围是需要重点加强的部分。(4)加筋格宾挡墙在地震荷载作用下挡墙起主要作用,格宾加筋也能提高路堤整体的稳定性,并在一定程度上提高格宾挡墙的抗震效果,格宾挡墙由于本身的刚度及重度均比路堤大,其在地震作用下有效的约束了路堤本体的位移,减少了路堤的整体变形。如加筋格宾挡墙需要加强,可在挡墙顶部后方需满铺土工格栅,中上部适当加短筋。更多还原

【Abstract】 Geosynthetic reinforced embankment under seismic load calculation and analysis is a very complex issue, involving fillers, reinforcing materials, embankment type, filler and reinforcement of the interaction and so on. Gabion retaining walls is only recently began to study China and the use of the new structure of the project site, the retaining wall of mechanism and the dynamic characteristics of the research are very limited. In this paper, Geotechnical special software Geo-Studio, combined with the general project site embankment and gabion retaining walls, the quasi static and dynamic finite element analysis, Reinforced embankment proposed a general optimization method, the mechanism of gabion retaining walls and the dynamic characteristics, the reinforced embankment and gabion retaining walls for the construction and promotion of reference.The content and results of this study are as follows:(1) Static method through the study found that vehicle load on the embankment in the overall stability under seismic loading has little effect.4 m-20 m minimum security standards for Embankment in September near the dangerous state under the standard required measures to strengthen, in seven degrees, eight seismic loads, the standard embankment basically stable. Grading and installation of platform can effectively improve the seismic stability of the embankment as a whole, especially for high embankment, the slope of platform can grow up into several general slope, effectively reduce the risk of landslides sliding range, improve the embankment the overall stability of the slope. For improving the overall stability of reinforced embankment and reduce the embankment under earthquake displacement, have an important role, is to improve the seismic stability of embankment effective means.(2) General summary of reinforced embankment optimization program, usually after grading and setting the platform embankment, embankment at the top of the upper platform at the first level is the most dangerous parts, need to focus on strengthening the embankment for different heights, according to the situation in the upper due to the short ribs strengthened. Specifically, less than the 20m standard embankment and embankment slopes in the upper top of the first platform, the general shop for geogrid, the laying of the short ribs to the upper right,20m-30m of standard embankment and embankment slopes, in the to the top of a platform, the full shop and grille and the upper part of the interval by 0.5-1m short ribs can be laid.(3) Gabion retaining walls with good seismic performance, especially for large earthquakes, the effect is obvious, retaining walls under earthquake loading, the maximum pressure at the top of the ground-breaking, bottom of the smaller, intermediate minimum, top and middle of the acceleration amplification factor greater than the bottom, under the action of the earthquake, the damage in the form of gabion retaining wall crack and impact the top of the deformation. After the reinforced gabion retaining wall 0.45H (H is wall height) to the top of the wall of the range, is the need to focus on strengthening the parts.(4) Gabion retaining walls under earthquake loading, wall play a major role. Gabion embankment reinforcement can improve the overall stability, and to some extent, improve the gabion retaining wall of the seismic effect. Gabion retaining wall because of their stiffness and severe than embankment large earthquake under the constraint of the effective displacement of embankment, reducing the overall deformation of the embankment. Gabion retaining walls such as reinforced by the strengthening of the back in the top of the geogrid to be paved, in the upper part of the short ribs need to be properly added.更多还原