海上大直径超长钢管桩打桩贯入特性及竖向静载试验分析  

Analysis of the Penetration Characteristics and Vertical Static Load Test of Large-diameter and Ultra Long Steel Pipe Piles Driven at Sea

作　　者：洪赛伟 HONG Sai-wei(CRCC Harbour and Channel Engineering Bureau Group Co.,Ltd.,Ningbo 315000,China)

机构地区：[1]中国铁建港航局集团有限公司,宁波315000

出　　处：《价值工程》2024年第9期129-132,共4页Value Engineering

摘　　要：针对海上大直径超长钢管桩承载力恢复时间长以及现场试验匮乏等问题,依托浙江省宁波舟山港六横公路大桥项目二期工程,对2.0m直径、113m长钢管桩进行初打和复打高应变测试以及静载测试,研究了大直径钢管桩沉桩贯入特性以及不同休止时间的承载力恢复特性。钢管桩沉桩后承载力存在显著的时间效应,沉桩6天后根据复打检测承载力恢复系数达到1.41,沉桩21天后根据轴向抗压试验承载力恢复系数达到2.22,比单桩设计极限值大22.15%。同时实测发现大直径钢管桩内外泥面高差较小,没有明显的土塞效应。该工程现场试验成果可为类似海上大直径钢管桩设计和施工提供技术参考。In response to the problems of long recovery time and lack of on-site testing for the bearing capacity of large-diameter and ultra long steel pipe piles at sea,relying on the second phase of the Liuheng Highway Bridge project in Ningbo Zhoushan Port,Zhejiang Province,high strain testing and static load testing were conducted on 2.0m diameter and 113m long steel pipe piles during initial and repeated driving.The penetration characteristics of large-diameter steel pipe piles and the bearing capacity recovery characteristics at different rest times were studied.There is a significant time effect on the bearing capacity of steel pipe piles after pile sinking.After 6 days of pile sinking,the recovery coefficient of bearing capacity reached 1.41 according to the re driving test,and after 21 days of pile sinking,the recovery coefficient of bearing capacity reached 2.22 according to the axial compression test,which is 22.15%higher than the design limit value of a single pile.At the same time,it was found through actual testing that the height difference between the inner and outer mud surfaces of large-diameter steel pipe piles is small,and there is no obvious soil blockage effect.The on-site test results of this project can provide technical reference for the design and construction of large-diameter steel pipe piles similar to those on the sea.

关 键 词：大直径钢管桩 高应变测试 贯入特性 时间效应 

分 类 号：TU473.1[建筑科学—结构工程]