Measurement of pile uplift forces due to soil heave in expansive clays
Measurement of pile uplift forces due to soil heave in expansive clays
复制标题
膨胀粘土中土体隆起引起的桩举力测量
DOI：
10.1139/cgj-2021-0079
复制
发表时间：
2022
影响因子：
3.6
通讯作者：
Burke T
中科院分区：
文献类型：
--
作者：
Burke T
桩基础是膨胀土地基中广泛采用的限制基础位移的基础。当粘土膨胀时，这些桩承受大的上举力（当粘土收缩时，这些桩承受下拉力）。估计这些力的适当方法还没有得到很好的理解，文献中提出的各种方法的估计值会导致很大的变化。桩土隆起产生的上拔力来自全尺寸现场试验中的应变测量，其中桩安装在高度膨胀土剖面中，并被淹没了几个月。将结果与现有的理论估计值进行比较，以评价估算桩中产生张力的最适当程序。结果表明，使用的弹性解决方案与预期的土壤隆起相结合的限制轴摩擦估计从总应力能力的方法提供了最合适的匹配的测量结果，无论是在桩中的发展张力的大小和形状的张力剖面沿着桩的深度。
Piled foundations are widely used to limit the movement of foundations in expansive clays. These piles are subjected to large uplift forces as the clay swells (and downdrag forces when it shrinks). The appropriate method to estimate these forces is not well understood, and estimates from various methods presented in literature result in large variations. The uplift force generated in piles by soil heave was derived from strain measurements in full-scale field tests where a pile was installed in a highly expansive soil profile and flooded for several months. The results were compared to available theoretical estimates to comment on the most appropriate procedure to estimate the generated tension in the pile. The results showed that the use of an elastic solution related to the expected soil heave combined with a limiting shaft friction estimated from total stress capacity methods provided the most appropriate match to the measured results both in terms of the magnitude of the developed tension in the pile and shape of the tension profile along the depth of the pile.