椅式桩板墙加固土质高边坡地段高填方路基模型试验研究  

Model Test Study of High Embankment in High Soil Slope Reinforced by Chair-shaped Pile Retaining Wall

作　　者：李婷 苏谦[2] 崔雅莉[2] 郭惠芹 LI Ting;SU Qian;CUI Yali;GUO Huiqin(School of Civil Engineering,Shijiazhuang Tiedao Univercity,Shijiazhuang 050043,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]石家庄铁道大学土木工程学院,河北石家庄050043 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《铁道学报》2021年第5期153-159,共7页Journal of the China Railway Society

基　　金：欧盟“玛丽居里学者”人才计划(101025354)。

摘　　要：西部山区地形起伏大,高边坡地段高填方路基工程需要采用新型支挡结构进行加固。为研究椅式桩板墙在土质高边坡地段高填方路基中加固的受力变形特性,进行缩尺模型试验。根据相似原理制作椅式桩板墙和土体模型,通过分级施加外部荷载,分别对结构位移、结构内力和土压力进行了测试和分析。结果表明:椅式桩板墙水平位移随加载推力的增大而增大,当加载推力大于40 kPa时,换算得到的水平位移值超过规范限值;主桩弯矩从上至下近似呈顺时针旋转90°后的“M”状分布,副桩弯矩自桩顶至岩土交界面近似呈三角形分布,岩土交界面以下呈倒梯形分布;挡土板土压力沿深度方向呈先轻微减小后增大的变化趋势,当加载推力大于40 kPa后,挡土板与主桩间出现了明显的土拱效应;由于主桩承受的土压力和弯矩值均大于副桩值,因而主桩成为椅式桩板墙的主要承载结构。该试验结果可为椅式桩板墙在土质高边坡地段高填方路基中的加固应用提供参考价值。Due to the undulating terrain of mountainous area in western China,the high embankment works in high soil slope area need to be reinforced with a new type of retaining structure named chair-shaped pile retaining wall.In order to study the characteristics of stress and deformation of chair-shaped pile retaining wall at the high-filled subgrade in high soil slope,a scale model test was performed.The model of chair-shaped pile retaining wall and soil was made according to the similarity principle.The landslide thrust was simulated by the graded loading to measure and analyze structural displacement,structural internal force and earth pressure respectively.The results show that the horizontal displacement of chair-shaped pile retaining wall increases with the increase of the loading thrust.When the loading thrust is more than 40 kPa,the converted horizontal displacement value exceeds specification limit.The bending moment of the main pile is distributed in the shape of M that rotates 90 degrees in clockwise along the pile depth.The bending moment of the auxiliary pile is distributed in the shape of triangle above the interface between rock and soil,and in the shape of inverted trapezoid below the interface between rock and soil.The earth pressure of retaining plank decreases slightly at first before increasing along the depth direction.When the loading thrust is more than 40 kPa,a significant soil arching effect occurs between the retaining plank and the main pile.Since the earth pressure and bending moment of the main pile are greater than the value of the auxiliary pile,the main pile of chair-shaped pile retaining wall becomes the main bearing structure.This test can provide some reference for the application of chair-shaped pile retaining wall in high embankment in high soil slope.

关 键 词：土质高边坡 高填方路基 椅式桩板墙 模型试验 受力变形特性 

分 类 号：TU443[建筑科学—岩土工程]