摘要
为系统研究桩体类型对复合地基支承路堤破坏模式及整体稳定性的影响,基于三维有限元分析方法开展了桩体破坏特性及地基剪切应变演化规律研究。采用全生命周期成本-效益分析方法对不同类型复合地基经济性进行了评估,以确定具备最优经济效益的复合地基设计方案。结果表明:路堤荷载作用下,桩体类型显著影响复合地基支承路堤破坏模式,随着桩体刚度增加,破坏模式从剪切破坏转变为弯曲破坏,破坏发展由同时破坏转变为渐进破坏;碎石桩复合地基塑性剪切应变沿路堤中心线呈渐进式发展趋势,而素混凝土桩复合地基剪切应变分别在路堤中心与坡脚区域呈渐进式与倒退式发展特征,最终形成贯通性临界滑动面;相较于同时提升全区域桩体强度,仅在路堤坡脚至坡肩之间设置高强度桩体即可显著提升路堤整体稳定性,表现出更优投资回报率与经济性。
To systematically investigate the influence of different pile types on the failure modes and overall stability of embankment supported by composite foundations,a three-dimensional finite element analysis method was employed to study pile failure characteristics and the evolution patterns of shear strain in foundation soils.A full lifecycle cost and benefit analysis framework was applied to evaluate the economic performance of various composite foundation configurations,thereby identifying the optimal design strategy with the highest cost efficiency.The results demonstrate that under embankment loading conditions,pile type significantly alters the failure mode of embankment supported by composite foundations.As pile stiffness increases,the failure mode transitions from shear failure to flexural failure,and the failure development pattern shifts from simultaneous failure to progressive failure.Specifically,in gravel pile composite foundations,the plastic shear strain in soils exhibits progressive development along the embankment centerline.In contrast,the shear strain evolution in plain concrete pile composite foundations displays distinct forward propagation at the embankment center and backward propagation at the slope toe region,ultimately forming a continuous critical sliding surface.Compared to strengthening piles across the entire area,installing high-strength piles only beneath the embankment slope toe to the shoulder of the embankment can significantly enhance the overall stability of the embankment,demonstrating superior return on investment and cost-effectiveness.
作者
刘剑
夏博洋
郑刚
Liu Jian;Xia Boyang;Zheng Gang(Cangzhou Qugang Expressway Construction Co.Ltd.;School of Civil Engineering,Tianjin University)
出处
《河海大学学报(自然科学版)》
北大核心
2026年第1期94-101,共8页
Journal of Hohai University(Natural Sciences)
基金
国家自然科学基金青年科学基金项目(52408385)
河北省交通运输厅科技项目(201405)。
关键词
路堤
复合地基
碎石桩
素混凝土桩
破坏模式
成本效益
embankment
composite foundation
gravel pile
plain concrete pile
failure mode
cost and benefit
