海上深厚淤泥层大直径钢管桩竖向抗压承载性能现场试验研究  

Field experimental study on vertical bearing capacity properties of large diameter steel pipe piles in marine deep thick muck stratum

作　　者：于海鹏 张震 罗震 Yu Haipeng;Zhang Zhen;Luo Zhen(Huaneng Zhejiang Clean Energy Branch,Hangzhou 310014,China)

机构地区：[1]华能国际电力股份有限公司浙江清洁能源分公司,杭州310014

出　　处：《工程勘察》2020年第10期29-34,共6页Geotechnical Investigation & Surveying

摘　　要：与码头、围填海等常规型式海洋工程不同,海上风电场多选址于开阔海域,风机所承受的风浪流作用更大且结构重心更高,因此风机所承受的倾覆力矩更大,风机基础刚度要求更高。本文基于杭州湾海域某海上风电场实际试桩工程,通过高应变动力检测及竖向抗压静载试验,得出该工程大直径钢管桩的极限承载力及承载力恢复系数。通过分析在不同桩顶荷载作用下桩的轴力分布及侧摩阻力变化情况,确定深厚淤泥层属摩擦桩不利地质条件,其产生的侧摩阻力作用较小且随深度变化不大;粉砂层属摩擦桩主要持力层,其埋深越大,侧摩阻力的作用发挥越充分。因此,在风电场风机机位微观选址时应尽量避免深厚淤泥层区域,并适当增加桩长以提高桩基础承载力。Compared with the conventional marine engineering such as the wharf and sea reclamation projects,the offshore wind farms are located in open sea,and the effects of wind,wave and current on the wind turbine are greater.As the center of the gravity of the structure is higher,the overturning moment of the wind turbine is larger;the rigidity requirement of the foundation is much higher.Based on the actual pile test project of the offshore wind farm in Hangzhou Bay,through the dynamic test method and the static loading tests,the bearing capacity behavior is studied in detail and the ultimate bearing capacity of the large diameter steel pipe pile is obtained.Through the analysis of the axial force and shaft resistance distribution of piles under different loads on the pile top,the unfavorable geological condition of the friction pile in the deep thick muck stratum is obtained,and the exerted shaft resistance is relatively small and few variation with the depth.The silt stratum is the main bearing layer of friction pile,and the deeper of the pile is buried,the more full the shaft resistance is exerted.So the micro site selection of the wind farm needs to avoid the deep thick muck stratum,and adding the pile length can increase the bearing capacity of pile foundation.

关 键 词：深厚淤泥层 大直径钢管桩 高应变动力测试 抗压静载 侧摩阻力 

分 类 号：TU473[建筑科学—结构工程]