多跨连续梁在桩板路基承载板设计中的应用  

Application of Multi-span Continuous Beam Model in the Bearing Plate Design of Pile-blank Subgrade

作　　者：郭帅杰 GUO Shuaijie(China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308

出　　处：《铁道工程学报》2022年第10期24-29,共6页Journal of Railway Engineering Society

基　　金：中国铁设科技开发计划项目(2019YY222101,2020YY241004,2021A241011);2019-2021年度铁道学会青托项目(2019QNRC001)。

摘　　要：研究目的:桩板路基在高速铁路、重载铁路、并线帮宽、车站路基、路桥过渡段等应用场景中得到广泛应用,具有自重轻、承载强、结构可靠的技术特征,但其结构设计仍严重依赖于工程经验和仿真分析。为解决桩板结构承载板内力分布解析计算问题,基于多跨连续梁模型,开展桩-土-板共同作用下的桩板路基承载板解析理论研究,确定承载板横断面及纵断面方向内力与挠度变形分布特征。研究结论:(1)桩板路基上部荷载通过承载板主要传递至桩基,承载板变形一般不超过0.5 mm, 1 m厚承载板已具备足够截面刚度,可满足一般设计工况;(2)承载板横断面承载以双向行车为最不利荷载因素,桩顶位置的承载板截面负弯矩数值远高于跨中正弯矩;(3)承载板纵断面内力分布更为复杂,边跨内力及变形远高于中间跨,宜采用纵断面不等跨布桩方式;(4)本研究成果可应用于桩板路基结构的承载板设计及配筋检算。Research purposes: Pile-blank subgrade is widely used in actual application scenarios, such as high-speed railway, heavy haul railway, side widening, station subgrade and road-bridge transition section, and has the technical characteristics of light weight, strong bearing capacity and reliable structure. However, its technical design still seriously depends on empirical method and simulation analysis. In order to obtain the analytical solution for the internal force distribution of bearing plate, multi-span continuous beam model was applied in the condition of pile-soil-plate joint action to determine the distribution characteristics of internal force and deflection deformation in transverse and longitudinal direction.Research conclusions:(1) Upper load is mainly transmitted to the pile top through bearing plate, and the bearing plated deformation is generally no more than 0.5 mm, and 1.0-meter-thick bearing plate has sufficient section stiffness during general design conditions, which can meet the general design conditions.(2) The bidirectional driving is the most unfavorable load factor in latitudinal direction, and the negative bending moment at pile top is much higher than the one at the span middle.(3) Internal force distribution in longitudinal direction is more complex, and the internal force and deformation at the side span are much higher than that at the middle span, so unequal pile layout in longitudinal direction is more reasonable.(4) The research results can be applied in the bearing plate design and reinforcement calculation for pile-blank subgrade structure.

关 键 词：桩板路基 多跨连续梁 承载板 弹性地基梁 内力分析 

分 类 号：TU470.3[建筑科学—结构工程]