桩承式加筋路堤荷载传递效率计算方法研究

Investigation of the calculation method of efficacy for geogridreinforced pile-supported embankments

鉴于土拱效应和张拉膜效应对路堤荷载传递及路堤沉降变形性状有重要影响,进行了室内模型试验,基于PIV技术分析路堤填料沉降分布规律从而研究土拱形态特征,试验结果表明路堤中的土拱可用高度为0.8倍桩净间距的抛物线描述.之后,基于新的土拱模型,提出了相应的路堤荷载传递效率计算方法.新方法在计算路堤荷载传递效率时同时考虑了土拱效应、张拉膜效应及地基土反力作用.最后,通过现有文献中模型试验结果及数值模拟结果对所提计算方法的正确性进行了验证.

Soil arching effect and tensioned membrane effect,have significant influences on load-transfer behavior and embankment settlement.Laboratory model tests were carried out to investigate the features of soil arching by analyzing the distribution of embankment fill settlement by PIV（particle image velocimetry）technique.It is showed that soil arching in embankments can be described with parabola with the height of 0.8 times of cap beam clear spacing.Then,based on the new soil aching model,the corresponding calculation method of efficacy was proposed.The major load-transfer mechanisms,namely soil arching effect,tensioned membrane effect and ground reaction were all taken into account at the same time when calculate the pile efficacy.Finally,the presented method was verified with laboratory model tests data and numerical simulation results of the publication to investigate its validity.