砂填料桩承式路堤宏观土拱形态与演化模型
发布时间：2018-08-07 10:35
【摘要】：基于目前研究很少关注土拱效应模型的适用条件和演化规律的现状,采用自制平面应变模型对砂填料桩承式路堤在不同桩间距下的宏观土拱形态,以及宏观土拱在桩间土下移过程中可能出现的演化现象进行探讨。模型试验将桩与土相互作用简化为桩间土挡板下移这一位移边界条件,配备可精确控制桩间土下移量的位移控制装置与摄影测量设备。每下移0.02 mm采集一张图片,采用图像分析软件追踪桩间土下移过程中路堤颗粒位移,实现全场位移量测。共进行3种填土高度下3种不同桩间距的模型试验。通过对9组试验填料内部滑移面的分析,揭示桩间土下移过程中均首先出现对称的三角形滑移面,即初始三角拱模型,之后继续增加桩间土下移量,初始三角拱模型存在2种不同的演化模式:在填土高度与桩距比1.8情况下,随桩间土下移量的增加滑移面逐级张开,称为三角多拱模型;在填土高度与桩距比≥1.8情况下,滑移面则逐级上移,演化为塔形多拱模型。最后,统计各模型的关键参数,为下一步土拱演化条件下的力学分析计算提供依据。
[Abstract]:Based on the fact that little attention has been paid to the applicable conditions and evolution rules of the soil arch effect model at present, the self-made plane strain model is used to study the macroscopic soil arch shape of the sand filled pile supported embankment under different pile spacing. The evolution of macro-soil arch in the process of soil displacement between piles is discussed. The pile-soil interaction is simplified as the displacement boundary condition of soil retaining plate in the model test, and the displacement control device and photogrammetric equipment can accurately control the soil displacement between piles. One image was collected with 0.02 mm downward, and the displacement of embankment particles was tracked by image analysis software in the process of soil movement between piles, and the displacement measurement of the whole field was realized. The model tests of three different pile spacing under three different fill heights were carried out. Based on the analysis of the slip surface in 9 groups of test fillers, it is revealed that the symmetrical triangular slip plane is first appeared in the soil movement between piles, that is, the initial triangular arch model, and then the amount of soil sliding between piles continues to increase. There are two different evolution models in the initial triangular arch model: when the ratio of fill height to pile distance is 1.8, the slip surface is opened step by step with the increase of soil displacement between piles, which is called triangle multi-arch model, and when the ratio of fill height to pile distance is 鈮，
本文编号：2169756
[Abstract]:Based on the fact that little attention has been paid to the applicable conditions and evolution rules of the soil arch effect model at present, the self-made plane strain model is used to study the macroscopic soil arch shape of the sand filled pile supported embankment under different pile spacing. The evolution of macro-soil arch in the process of soil displacement between piles is discussed. The pile-soil interaction is simplified as the displacement boundary condition of soil retaining plate in the model test, and the displacement control device and photogrammetric equipment can accurately control the soil displacement between piles. One image was collected with 0.02 mm downward, and the displacement of embankment particles was tracked by image analysis software in the process of soil movement between piles, and the displacement measurement of the whole field was realized. The model tests of three different pile spacing under three different fill heights were carried out. Based on the analysis of the slip surface in 9 groups of test fillers, it is revealed that the symmetrical triangular slip plane is first appeared in the soil movement between piles, that is, the initial triangular arch model, and then the amount of soil sliding between piles continues to increase. There are two different evolution models in the initial triangular arch model: when the ratio of fill height to pile distance is 1.8, the slip surface is opened step by step with the increase of soil displacement between piles, which is called triangle multi-arch model, and when the ratio of fill height to pile distance is 鈮，
本文编号：2169756
本文链接：https://www.wllwen.com/kejilunwen/jiaotonggongchenglunwen/2169756.html
