深圳地铁五号线海积淤泥地层基坑围护桩插入深度的研究

摘要

海积淤泥地层具有天然含水量高、渗透性低、压缩性高及抗剪强度低等特点,因此在海积淤泥地层修建地铁车站时,车站基坑围护结构的稳定性对安全施工至关重要。采用FLAC程序对海积淤泥地层地铁车站基坑围护结构桩体插入深度进行研究,分析桩体最大位移、最大剪力及基坑周边地表沉降等与插入深度的关系,给出适合于海积淤泥地层的桩体插入深度,并提出插入深度不足时的应对措施。%Marine mud formation has the characteristics of high natural water content,low permeability,high compressibility and low shear strength.Therefore,when building subway station in marine mud formation,the stability of retaining structure for foundation pit plays a vital role in safe construction.In this paper,the depth of penetration of retaining pile for the foundation pit of subway station in marine mud formation was studied using FLAC program,and then the relationship between the depth of pile penetration and the maximum displacement,maximum shear strength and surface settlement around foundation pit were separately analyzed.Finally,the depth of pile penetration for marine mud formation was provided and the countermeasures for insufficient penetration were put forward.