桩承式加筋垫层路堤荷载分担改进计算模型  

Improved calculation model of load sharing of pile-supported reinforced cushion embankment

作　　者：何忠明[1,2] 罗仕佳 王盘盘 HE Zhongming;LUO Shijia;WANG Panpan(School of Transportation Engineering,Changsha University of Science and Technology,Changsha 410114,China;National Engineering Research Center of Highway Maintenance Technology,Changsha University of Science and Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学交通运输工程学院,湖南长沙410114 [2]长沙理工大学公路养护技术国家工程研究中心,湖南长沙410114

出　　处：《中南大学学报（自然科学版）》2024年第6期2286-2294,共9页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51978084)。

摘　　要：桩承式加筋垫层路堤中的关键荷载传递机制是多种现象的组合,包括路堤填土中的土拱效应、加筋垫层的张拉膜效应和地基土的支撑作用,然而,目前针对此方面的研究尚不完善。本文首先以考虑土体被动土压力发挥程度及桩间土应力非均匀分布改进的Hewlett土拱模型为改进载体;其次,假定加筋垫层为上、下部受均布荷载作用的简支梁,截面拉应力完全由加筋体承担,压应力完全由垫层材料承担,同时考虑地基土反力与梁最大挠度相关,引入地基反应系数,从而建立改进的桩承式加筋垫层路堤荷载分担计算模型;最后,通过工程实例与模型参数分析,验证本文计算模型的可靠性与准确性。研究结果表明:在路堤填筑过程中,土拱效应逐渐完全发挥,促进路堤荷载向桩体转移;随着地基土固结,桩体承担的路堤荷载也在逐渐增大;路堤填土高度、填土内摩擦角、桩间距对桩体荷载分担影响较大,加筋体抗拉模量对其影响较小。The key load transfer mechanism in pile-supported reinforced cushion embankment is a combination of various phenomena,including soil arching effect in embankment filling,tensile membrane effect of reinforced cushion and supporting effect of foundation soil.However,the current research in this aspect is not perfect.In this paper,firstly,the improved Hewlett soil arch model based on the consideration of the degree of passive earth pressure and the non-uniform distribution of soil stress between piles was used as the improved carrier.Secondly,it was assumed that the reinforced cushion was a simply supported beam subjected to uniform load at the upper and lower parts.At the same time,considering the correlation between the soil reaction force and the deformation at the maximum deflection of the beam,an improved load sharing computation model of pile-supported reinforced cushion embankment was set up,and the foundation reaction coefficient was introduced.Finally,the credibility and accuracy of the computation model was proved by engineering examples and model parameter analysis.The results show that in the process of embankment filling,the soil arching effect is gradually fully exerted,thus promoting the transfer of embankment load to the pile.With the consolidation of the foundation soil,the embankment load borne by the pile body gradually increases.The height of embankment fill,the internal friction angle of fill and the pile spacing have great influences on the load sharing of piles,while the tensile strength of reinforcement has little effect on it.

关 键 词：道路工程 桩承式加筋垫层路堤 土拱效应 张拉膜效应 荷载分担计算模型 

分 类 号：TU43[建筑科学—岩土工程]