为了从更深层次理解土拱效应的工作性状,在总结桩承式路堤土拱效应中等沉面、桩体荷载分担比等问题的基础上,比较了几种桩体荷载分担比的计算方法,阐述了动荷载在桩承式路堤中的传递机理,分析了土拱效应发挥程度对动应力的影响,最后给出桩承式路堤中动应力的计算方法。研究结果表明:等沉面与土拱高度可用临界填土高度进行归一化描述,临界填土高度与桩间净距呈线性关系;桩体荷载分担比的大小与工况有关,几种计算方法有各自的适用条件;陈云敏的计算方法与实测值拟合度较高;动荷载的传递也受土拱效应的影响,随着动荷载循环次数的增加,土拱效应存在先强化后弱化的现象。
In order to understand the characteristics of soil arching effect deeply, on the basis of summarizing equal settlement plane and pile efficacy in the soil arching effects of pile-supported embankments, the several calculation methods on pile efficacy were compared. The transfer mechanism of dynamic load in pile-supported embankment was elaborated, and the influence of degree of soil arching effect on dynamics stress was analyzed. Finally, the method for calculating the dynamic stress in pile-supported embankments was given. The results show that the equal settlement plane and soil arch height can be normalized description with critical filling height, and the critical filling height is linear with the spacing between piles. The values of pile efficacy are related to the working conditions, and the calculation methods have their applicable conditions. The calculation method of Chen is fitting with measured value. The dynamic loads are also affected by the soil arching effects, and the soil arching effect appears strengthened firstly and then weakened with the increase of cycle number of dynamic loads.