红黏土地层开口管桩土塞效应模型试验研究

发布时间：2018-11-02 08:24

【摘要】：为研究红黏土上硬下软地层中开口管桩的土塞问题,对3种不同直径的镀锌开口管桩进行室内静压沉桩模型试验,以分析单桩、群桩土塞高度的变化规律和红黏土地层管桩土塞效应的机理。结果表明:土塞高度随着管桩压入深度的增大不断增大,当桩压入到红黏土层上硬下软界面(硬塑层和可塑层交界面)后,土塞高度停止增长,持续到压入可塑层一定深度后土塞高度继续增长直到压桩结束,表明土层类型对土塞效应影响显著;土塞高度与压桩顺序关系并不明显,单桩与群桩的土塞高度基本相同;所有的管桩均在到达红黏土软塑层时出现土塞完全闭合的情况,管桩由硬塑层打入软塑层时,土塞闭塞作用很强;从软塑层打入持力层过程中,土塞增量填充率变大较明显,土塞闭塞作用减弱。
[Abstract]:In order to study the soil plug problem of open pipe pile in hard and soft stratum of red clay, three kinds of zinc-plated open pipe piles with different diameters were tested by static pressure pile model test in order to analyze single pile. The variation law of pile height and the mechanism of tube-pile-soil plug effect in red clay formation. The results show that the height of soil plug increases with the increase of the penetration depth of the pipe pile. When the pile is pressed into the soft interface of the red clay layer (the interface between the hard plastic layer and the plastic layer), the height of the plug stops to increase. The soil plug height continues to increase until the pile is finished after the plastic layer is pressed into a certain depth, which indicates that the type of soil layer has a significant effect on the soil plug effect. The relationship between the height of soil plug and the sequence of pile pressing is not obvious, and the height of soil plug of single pile and group pile is basically the same. When all pipe piles reach the soft plastic layer of red clay, the soil plug is closed completely. When the pipe pile is pushed into the soft plastic layer by hard plastic layer, the blocking effect of soil plug is very strong. During the penetration of the soft plastic layer into the bearing layer, the increasing filling rate of the soil plug is larger and the blocking effect of the plug is weakened.
【作者单位】：广西科技大学土木建筑工程学院;
【基金】：国家自然科学基金项目(51469005) 广西自然科学基金项目(2015GXNSFAA139257;2015GXNSFAA139270) 广西科技大学研究生教育创新计划项目(GKYC201627) 广西高校科研项目(2013YB177)
【分类号】：TU473.1;TU446

【相似文献】