【作者】 张杰；

【导师】 郭院成；

【作者基本信息】 郑州大学 ， 结构工程， 2011， 硕士

【摘要】 随着我国基本建设的发展,高填方路基在公路建设中得到越来越多的应用。软土地区的路基由于其渗透系数小,逐层填方过程中缺乏良好的排水通道,在填方路基荷载作用下,随着填方高度的增加会产生呈线性增加的超孔隙水压力,土体的有效应力难以得到有效增加,影响路基的稳定,拖延施工进度。高填方路基后处理技术有效解决了这个技术难题。高填方路基的沉降变形为工程界普遍关注的问题。本文在前人研究的基础上针对无砂砼小桩后处理高填方路基的沉降变形随着设计参数的变化发展规律展开研究。通过数值模拟方法,建立无砂砼小桩后处理模型,建立桩长、桩径、桩间距、后处理填方平台高度变化时的有限元模型,进行系统的数值分析,得到下列结论：(1)无砂砼小桩后处理技术在成孔形成桩体过程中,由于桩体的良好排水通道作用,可以加速排水固结,加速固结沉降,总沉降小；后期填方荷载由后处理复合地基所承担,工后沉降小；(2)桩径、桩间距、后处理填方平台高度不变时,加大桩长可以加速固结沉降,工后沉降随着桩长的增加而减小,总沉降量减小；(3)桩长、桩间距、后处理填方平台高度不变时,增大桩径可以加速固结沉降,减小工后沉降,总沉降量减小;(4)桩长、桩径、后处理填方平台高度不变时,减小桩间距可以加速固结沉降,减小工后沉降,总沉降量减小；(5)桩长、桩径、桩间距不变,增加后处理填方平台高度可以减小沉降量,减小工后沉降。更多还原

【Abstract】 With the development of infrastructure, high-fill embankment in highway construction has been more and more used. Because t the permeability of the soft soils is very small, and there is no good drainage channels in the fill loads, excess pore water pressure will increase linearly with the process of filling increases, threatening the stability of the roadbed and affecting construction progress. The post-processing technique effectively solves the problem. At present, post-processing techniques used is non-sand concrete micro-pile technology.The settlement of high embankment is the general concern of the society of the engineering. Based on previous studies, this article researches the settlement of high fill embankment which uses non-sand concrete micro-pile technology and the influence of the parameters change with the law of development. By numerical simulation, the establishment of a small pile of sand concrete post-processing model, a pile length, pile diameter, pile spacing, post-treatment fill platform height fill the finite element model, concluded that:(1) Non-sand concrete micro-pile technology, due to the good drainage of the pile, can speed up the drainage and consolidation, can decrease the total settlement; post-filling load is controlled by the composite foundation;(2) When the pile diameter, pile spacing and the post-processing platform are a fixed value, the greater length of the pile can speed up the consolidation settlement, can decrease the settlement of post-fill amount and can reduce the total settlement amount;(3) When the pile spacing, pile length and the post-processing platform are a fixed value, the greater diameter of the pile can speed up the consolidation settlement, can decrease the settlement of post-fill amount and can reduce the total settlement amount;(4) When the pile diameter, pile length and the post-processing platform are a fixed value, the smaller spacing of the pile can speed up the consolidation settlement, can decrease the settlement of post-fill amount and can reduce the total settlement amount;(5) When the pile diameter, pile length and pile spacing are a fixed value, the increased post-processing platform can reduce the total settlement and the settlement of post-fill amount.更多还原