岩层设承力盘的DX嵌岩桩承载特性模型试验  

Model test on bearing characteristics of DX rock-socketed pile with bearing plate in strata

作　　者：武鹏 张德华 刘勇 李航 王玉超 WU Peng;ZHANG Dehua;LIU Yong;LI Hang;WANG Yuchao(China Highway Engineering Consultants Corporation,Beijing 100048,China;Tunnel and Underground Engineering Research Center of Ministry of Education,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]中国公路工程咨询集团有限公司,北京100048 [2]北京交通大学隧道及地下工程教育部工程研究中心,北京100044

出　　处：《北京交通大学学报》2023年第3期26-34,共9页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家自然科学基金(51478035);国家重点研发计划(2019YFC1509700)。

摘　　要：针对DX嵌岩桩承载特性研究相对比较滞后的问题,通过设置4组模型试验,分别研究嵌岩深度、承力盘盘径比、承力盘盘位对桩极限承载力、桩顶沉降的影响,并结合DX嵌岩桩与直孔嵌岩桩承载特性对比,对DX嵌岩桩承载力影响因素及承载机理进行分析.研究结果表明:承力盘盘径对DX嵌岩桩的承载特性影响最为显著,最优盘径比为2.5~3.0;竖向荷载作用下,DX嵌岩桩是一种摩擦端承桩,在荷载增加的过程中,DX嵌岩桩承力盘盘上侧摩阻力、盘阻力、盘下侧阻力、端阻力依次发挥作用;同等桩长,岩层设置承力盘的DX嵌岩桩承载特性优于同等条件的直孔嵌岩桩,DX嵌岩桩的承载力约为直孔嵌岩桩的1.5~1.7倍,且沉降控制效果更佳.The research on the bearing characteristics of DX rock-socketed piles is relatively limited.In this study,four sets of model tests are conducted to examine the effects of rock-socketed depth,bear⁃ing disk diameter,and bearing disk position on the pile’s ultimate bearing capacity and pile top settle⁃ment.By comparing the bearing characteristics between DX rock-socketed piles and straight-hole rock-socketed piles,the influencing factors and bearing mechanism of DX rock-socketed piles are ana⁃lyzed.The results show that the bearing disk diameter has the most significant impact on the bearing characteristics of DX rock-socketed piles,and the optimal disk diameter ratio is 2.5~3.0.Under verti⁃cal load,DX rock-socketed piles act as friction end-bearing piles.During the load increase process,DX rock-socketed piles play different roles in turn,including upper lateral friction resistance,disk re⁃sistance,lower lateral resistance,and end resistance.The bearing capacity of DX rock-socketed piles with the same pile length and bearing disk is superior to that of straight-hole rock-socketed piles under the same conditions.The bearing capacity of DX rock-socketed piles is about 1.5 to 1.7 times higher than that of straight-hole rock-socketed piles,and the settlement control effect is better.

关 键 词：岩土工程 DX嵌岩桩 极限承载力 嵌岩深度 模型试验 

分 类 号：TU473[建筑科学—结构工程]