海洋平台桩基安装过程对土阻力的影响分析  

Analysis of Influence of Offshore Pile Driving Process on Soil Resistance

作　　者：李飒[1] 贾志远[1] 康思伟 孙振平 LI Sa JIA Zhi-yuan KANG Si-wei SUN Zhen-ping(School of Civil Engineering, Tianjin University, Tianjin 300072, China China National Offshore Oil Corporation Shanghai Branch, Shanghai 200335, China)

机构地区：[1]天津大学建筑工程学院,天津300072 [2]中海油上海分公司,上海200335

出　　处：《船舶工程》2016年第12期63-68,共6页Ship Engineering

基　　金：国家973项目(2014CB046800);国家重大专项(2011ZX05056-002-01);自然科学重点基金(51239008)

摘　　要：影响桩基可打入性分析结果的因素有很多,很多学者对此进行了研究,但受到各种因素的限制,对于打桩过程的影响鲜有涉及。文章针对某海域现场两根试验桩的实测数据、室内试验数据和现场CPT(静力触探试验)结果,采用波动方程方法,研究在砂土中打桩时的打桩过程对打桩土阻力(SRD)的影响。分析结果显示,在砂土中,即使桩径达到2.438 m,仍然可以形成闭合的土塞;相同土质条件下,打桩过程中不同的锤击能量导致了不同的锤击数,并进一步产生了SRD的差异,这说明打桩所导致的侧阻退化程度与打桩过程有关。研究结果表明使用波动方程方法评价砂土中打桩的SRD精度要优于传统方法;在本次试验条件下,对于形成土塞的情况,英国帝国理工桩基(ICP)方法的计算结果偏小。Many factors affect the results of pile drivability analysis and many researchers have made some works on it, but the influence of pile driving process on it is rarely involved. Based on the in situ tests of two piles, CPT results and the results from indoor tests, the influence of pile driving process on soil resistance to driving in the sand is studied by wave equation method. The analysis results show that the soil plug could form in the pile even if pile diameter is 2.438 m when pile driving in sand. Under the same soil condition, different impact energy in driving leads to the difference of blow counts and then the difference of SRD. This means that the degradation of pile friction caused by pile driving is related to the pile driving process. The CPT-based method used to evaluate the accuracy of SRD in sand is better than traditional methods. In this analysis, the calculation results of the ICP method are smaller in the case of soil plug closure.

关 键 词：打桩过程 CPT 承载力 土阻力 

分 类 号：TU473.1[建筑科学—结构工程]