CFG桩复合地基加固桥头深厚软基  

Improvement of deep and thick soft foundation at the end of a bridge by using CFG pile composite foundation

作　　者：何宁[1] 娄炎[1] 娄斌[1] 

机构地区：[1]南京水利科学研究院,江苏南京210029

出　　处：《水利水运工程学报》2010年第4期89-94,共6页Hydro-Science and Engineering

摘　　要：深厚软基经过CFG桩复合地基处理后,能够满足高路堤桥头控制工后沉降的要求.路堤预压期间桩间土压力总体呈上升趋势,预压期间桩间土与桩顶承受的荷载在不断地调整,桩土应力比呈下降趋势,直到预压后期基本稳定在18.7.路堤下刚性桩复合地基在桩土应力比、桩土荷载分担上与刚性基础下刚性桩复合地基有较明显的差异.本工程实测资料表明桩、土承载能力仅仅发挥20%,尚有较大潜力.对于刚性桩复合地基,扩大桩间距的同时在桩顶设置足够面积和刚度的桩帽,增大桩的置换率,以保证刚性桩复合地基刚度是发挥桩、土承载能力的有效途径.By using CFG pile composite foundation to improve the deep and thick soft foundation at the end of a bridge,the post-construction settlement can be controlled and meet the requirements of the relevant criterion.During the preloading period,the load acting on the soil of the composite foundation increases,and the load acting on the pile and the soil of the composite foundation continuously adjusts.The ratio of the load acting on the pile and the soil decreases.Finally,it reaches a steady value of 18.7.It is the basic characteristic of the rigid pile composite foundation.The experimental data from a case of CFG pile composite foundation show that only 20% carrying capacity of piles and soil is used,and their potential carrying capacity is great.For the rigid pile composite foundation,it is important to expand the spacing between piles and construct a sufficient size and stiffness pile cap to increase the rate of replacement of piles.It is an effective measure to utilize the high carrying capacity of rigid piles and soil by increasing the rigidity of the embankment and foundation.

关 键 词：CFG桩 复合地基 高速公路 桥头 深厚软基 工后沉降 

分 类 号：U416.1[交通运输工程—道路与铁道工程] TU471.8[建筑科学—结构工程]