太原理工大学学报2025，Vol.56Issue(2)：199-206,8.DOI:10.16355/j.tyut.1007-9432.20230459
阶梯桩竖向承载性能模型试验研究
Model Test Study on Vertical Bearing Capacity of Stepped Piles
摘要
Abstract
[Purposes]The stepped pile with variable cross-section is a new pile type that is im-proved on the basis of the pile with equal cross-section,but its loading and deformation are relatively complex,and the processes of exerting lateral friction resistance,end resistance at variable section,and pile end are not understood.[Methods]In this paper,the vertical bearing capacities of ordinary pile and stepped pile were studied by indoor model tests with the graded load application method.[Findings]Under identical conditions,the settlement of the stepped pile is reduced by 33%,and its bearing capacity of unit volume is increased by 19%compared with those of the pile with equal cross-section,indicating that the stepped pile has the advantage of reducing the settlement and better bearing capacity of unit volume.The axial force of the stepped pile decreases sharply at the position of the vari-able cross-section.It is shown that the existence of a variable section affects the axial force transfer of the stepped pile.In the initial stage of loading,as the load on the pile top increases,the ratio of the lat-eral friction resistance to the load on the pile top gradually increases,and the ratio of end resistance at the variable cross-section and the end to the load on the pile top gradually decrease;When the lateral frictional resistance reaches its limit,the ratio of the lateral frictional resistance to the pile top load gradually decreases,and the ratio of the end resistance at the variable cross-section and the end gradu-ally increases,but the ratio of the end resistance at the variable cross-section tends to be stable first,which indicates that the soil at the variable cross-section is destroyed first.According to the Terzaghi theory,the formula for calculating the end bearing capacity at the variable cross-section of stepped piles has been revised,and the reliability of this theoretical method has been verified by comparing it with experimental results.关键词
阶梯桩/承载力/载荷试验/变截面端阻力/P-S曲线Key words
stepped pile/bearing capacity/load test/end resistance at variable section/P-S curve分类
建筑与水利引用本文复制引用
刘书杰,刘正,王腾,贺武斌,崔永强..阶梯桩竖向承载性能模型试验研究[J].太原理工大学学报,2025,56(2):199-206,8.基金项目
国家自然科学基金资助项目(52078483) （52078483）
