【作者】 周材栋；

【导师】 姚令侃；

【作者基本信息】 西南交通大学 ， 防灾减灾工程及防护工程， 2010， 硕士

【摘要】 随着我国西部大开发的开展,越来越多的高速公路开始向西部延伸。西部地区大部分为典型的山地地形,在这种地方修建高速公路,不可避免地会遇到大量的半挖半填及陡坡路堤,必须采用支挡结构来保证路堤的稳定,以确保公路运输的安全。而衡重式挡土墙以胸坡很陡,下墙墙背仰斜,可减少挡土墙的设计高度和施工土石方开挖量的优点得到广泛应用。四川大部分地区位于地震高烈度区,对挡土墙进行抗震设计尤为重要。目前各国对路基、挡土墙的自振频率研究很少,仍采用静力法计算地震作用,我国规范是以重力式挡土墙为典型墙型,只考虑水平地震力作用进行抗震设计,还有日本、美国和新西兰等国规范亦没有考虑竖直地震力的作用,但欧洲规范却考虑了。本文通过现场震害调查、大型的振动台实验,结合有限元ANSYS数值模拟,探讨了挡土墙在地震作用下的动力响应。本文主要进行了以下几个方面的研究工作：1、通过挡土墙振动台实验得出了墙后土的水平加速度和动土压力沿墙高的分布规律,结合通用有限元分析软件ANSYS对实验进行数值模拟,将实验结果与数值模拟结果对比,两者基本吻合,为校正数值模拟模型提供了实验依据。2、运用ANSYS对两种路肩墙进行模态分析,提取了前五阶的频率和振型,按照4m、6m、8m、10m和12m 5种墙高,对比衡重式与仰斜式的结果,得出了自振频率随墙高的增大而减小；同一种高度,衡重式的基频比仰斜式要大。3、运用ANSYS对土基上的8m墙高的衡重式挡土墙进行瞬态分析,采用汶川波实震波形,按照0.1g、0.2g、0.4g、0.6g、0.8g和0.9g六种输入波峰值,分析了在仅受水平地震力、仅受竖直地震力和水平地震力与竖直地震力共同作用三种工况下墙顶最大水平位移随震级的关系,得出水平地震力对挡土墙水平位移起主导作用,竖直地震力影响很小,可以忽略不计。更多还原

【Abstract】 With the propulsion of China’s western development, more and more highway began to extend to the west. Most of the western region is a typical mountainous topography. In such places to building highways, it will inevitably encounter a lot of half-dug half-filled and steep embankments, retaining structures must be used to guarantee the stability of the embankment in order to ensure that the road transport security. The balance weight retaining wall’s chest-slope is very steep and its back wall is tipsy, so it is widely used because it can reduce the height of retaining wall designed and the amount of earth excavation. Most parts are located in a high-intensity earthquake zone in Sichuan Province, seismic design of retaining walls is particularly important.Currently the studies of self-vibration frequency of roadbed and retaining structures are few, using static method to calculate seismic effect. Gravity retaining wall based on our standards for a typical wall type in our country, and only considers the role of horizontal seismic force to conduct seismic design seismic forces. But also Japan, the United States and New Zealand norms have not been considered the role of vertical seismic forces, but European standards are taken into account. In this paper, by earthquake damage surveys, large-scale shaking table test, combining with ANSYS finite element numerical simulation to explore the role of the retaining wall under seismic dynamic response. In this paper, I carried out research in the following areas:1.Through the retaining wall shaking table test, I has reached the distribution of the horizontal acceleration and the seismic active earth pressure along the wall high, combining with general-purpose finite element analysis software ANSYS to simulate the experiment, the experimental results and numerical simulation result. They come to a conclusion that correct numerical simulation model providing an experimental basis.2. Using ANSYS modal to analyze two types of shoulder wall, I extract ahead five frequencies and mode shape. According to 4m,6m,8m,10m and 12m, contrasting the conflation of the balance weight retaining wall and steep retaining wall,1 have obtained that the vibration frequency decrease with the increase of the high walls; at the same height, weight balance type of vibration frequency larger than the steep type.3. Using ANSYS transient analysis about the 8m-high balance weight retaining wall on soil based, using Wenchuan seismic wave, in accordance with 0.1g,0.2g,0.4g,0.6g,0.8g and 0.9g 6 kinds of input-wave peak, analyze the subject only to the horizontal of seismic forces, subject only to vertical seismic force and horizontal earthquake force and joint action of vertical earthquake force, conclude the maximum horizontal displacement of top of the wall with the earthquake magnitude, the horizontal of seismic derived the retaining wall displacements play a leading role, vertical seismic forces has little effect and can be negligible.更多还原