摘要
针对常规楔形桩桩底进行注浆或夯扩施工形成的扩底楔形桩,具有单位材料利用率高、竖向桩侧摩阻力和桩端阻力较常规等截面桩高的技术优点。然而针对该新型桩竖向承载力提高幅度的定量试验研究相对较少。基于室内模型试验方法,开展两种桩周土(砂性土和黏性土)情况下扩底楔形桩竖向抗压承载力特性试验,测得桩顶荷载-沉降关系曲线,不同荷载等级下桩侧摩阻力、桩端阻力的分布规律及分担比;同时,开展等体积混凝土用量情况下的常规扩底桩的竖向抗压承载力特性试验作为对比分析。研究结果表明,试验条件下,砂性土中,等混凝土用量扩底楔形桩的极限承载力约为常规扩底桩的1.25倍;黏性土中扩底楔形桩和常规扩底桩的极限承载力比砂土中分别提高了11.1%和66.7%。
Belled wedge piles with enlarged wedge base through grouting or ramming present high material usage ratio, and benefit the side friction and tip resistance comparing to those of traditional equal section piles. However, few studies focused on quantitative analysis of improvement ratio of vertical bearing capacity of the new type pile. The vertical bearing capacities of belled wedge piles, the load-settlement curve, the distributions of side friction and tip resistance, and load share ratio were measured in sandy and clayey soils. The vertical bearing capacities of traditional belled pile with the same concrete volume were compared as control. The results show that the ultimate bearing capacity of belled wedge pile is nearly 1.25 times that of traditional belled pile embedded in sand. The ultimate bearing capacities of belled wedge pile and traditional belled pile increase 11.1% and 66.7% when they are embedded in clay than in sand, respectively.
作者
孔纲强
顾红伟
车平
任连伟
彭怀风
KONG Gang-qiang GU Hong-wei CHE Ping REN Lian-wei PENG Huai-feng(Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing, Jiangsu 210098, China , Eastern China Geological ＆ Mining Organization for Non-Ferrous Metals in Jiangsu Province, Nanjing, Jiangsu 210007, China School of Civil Engineering, Henan Polytechnic University, Jiaozuo, Henan 454000, China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2017年第2期361-367,共7页
Rock and Soil Mechanics
基金
国家自然科学基金(No.51278170
No.51306080)
江苏省自然科学基金项目(No.BK2012478)~~
关键词
桩基
压缩
极限承载力
扩底楔形桩
模型试验
pile foundation
compression
ultimate bearing capacity
belled wedge pile
model test
