路堤下刚性桩复合地基的经验设计方法  

Experimental Research on Design Method for Rigid Pile Composite Foundation under Embankment

作　　者：娄炎[1] 何宁[1] 娄斌[1] 

机构地区：[1]南京水利科学研究院,南京210029

出　　处：《铁道工程学报》2011年第9期17-22,共6页Journal of Railway Engineering Society

摘　　要：研究目的:路堤下刚性桩复合地基的设计目前大都是沿用刚性基础复合地基设计方法进行,设计结果与实际出入很大,造成刚性桩复合地基造价很高,影响它广泛使用。为了使刚性桩在复合地基中成为路堤荷载承担的主力及刚性桩的高承载能力特性得到较好发挥,本课题开展了大规模的现场试验研究。研究结论:研究表明刚性桩复合地基经验设计方法遵循两条基本原则,一要发挥桩的主导作用,二要充分发挥桩高承载特性。为此,确定桩、土荷载承担比确定为3,扩大桩间距和提高置换率,是实现这两条原则的有效途径。按建议的方法设计刚性桩复合地基时,桩只要打到持力层,路堤的沉降变形是可以控制的,能满足规范对桥头工后沉降的要求,其造价也是可以大大降低的。Research purposes： The design method for the rigid composite foundation is commonly used for the rigid composite foundation under embankment and the design result is big different from the actual situation. It brings about the high cost of the rigid pile composite foundation to cause the impact on the wide application of the rigid pile composite foundation. In order to better application of the rigid pile in the composite to enhance the bearing capacity of the embankment and bring the good bearing capacity of the rigid pile into play, the experimental research is done in large - scale on the design method for the rigid pile composite foundation under embankment.Research conclusions：The research shows the design method for the rigid pile composite foundation under embankment should follow the two basic principles： one is to bring the rigid pile into the major play and the other is to bring the good bearing capacity of the rigid pile into play. In order to achieve these targets, the effective way is to determine the bearing ratio between the pile and as three, enlarge the distance between piles and enhance the replacement rate. If the rigid composite foundation is designed with the proposed method and the pile reaches at the supporting course, the settlement deformation of the embankment can be controlled to meet the specification requirement of the post - construction settlement for the bridgehead and the cost can be largely reduced .

关 键 词：高速公路 路堤.冈巾f生桩复合地基 土拱效应 工后沉降 设计方法 

分 类 号：TU443[建筑科学—岩土工程]