摘要
管桩复合地基法在处理高速公路高填方桥头深厚软基时造价较高。在管桩间设置水泥搅拌桩,加大管桩间距,同时使桩间土的承载力适当提高,形成长短桩复合地基。详细介绍了长短桩复合地基在加固桥头深厚软基的具体方法,并对加固效果进行了分析。结果表明,经过长短桩复合地基处理后,通过减少总沉降量来控制工后沉降,减少幅度超过90%;填土荷载向管桩桩帽与搅拌桩桩顶集中,桩帽平台上的平均土压力是桩间土压力均值的4.5倍,搅拌桩桩顶平均压力是桩间土压力均值的1.7倍,路堤产生了土拱效应,使桩的高承载能力特性得以发挥。提高桩体承载比例的主要途径是提高桩的置换率,增大桩帽面积。
Pipe pile composite foundation is used to strengthen deep soft ground at the end of bridge,and its cost is very high.Cement mixing piles are put into the interval of pipe pile to form composite foundation long-short piles.This composite foundation can improve the bearing capacity of piles and reduce cost.Construction technology of the composite foundation in strengthening deep soft ground at the end of bridge is introduced,and the strengthening effect is also present.Results show that deep soft ground strengthened by composite foundation with long-short piles reduce the total settlement to control post-construction settlement by 90%.The fill load concentrate toward to the pipe pile cap and mixing pile top,average earth pressure on the pile cap platform is 4.5 times as large as that on the soilarea between piles,and on the mixing pile top is 1.7 times. Soil arching effect of embankment will appeare.Replacement ratio is the main factor for increasing proportion of pile bearing load and the sizes of pile cap.
出处
《施工技术》
CAS
北大核心
2009年第10期90-93,共4页
Construction Technology
关键词
桥头
深厚软基
长短桩
复合地基
土拱效应
工后沉降
end of a bridge
deep soft ground
long-short piles
composite foundation
soil arching effect
post-construction settlement
