基于实测的挤密砂桩复合地基沉降算法研究  

Settlement calculation method for sand compaction piles under water based on in-situ measurement

作　　者：寇晓强[1,2,3] 于健 胥新伟[1,2,3] 宋神友 高潮[1,2,3] KOU Xiao-qiang;YU Jian;XU Xin-wei;SONG Shen-you;GAO Chao(CCCC Tianjin Port Engineering Institute,Ltd.,Tianjin 300222,China;Key Laboratory of Port Geotechnical Engineering,Ministry of Transport,PRC,Tianjin 300222,China;Key Laboratory of Geotechnical Engineering of Tianjin,Tianjin 300222,China;Guangdong Highway Construction Co.,Ltd.,Zhongshan 528400,China)

机构地区：[1]中交天津港湾工程研究院有限公司,天津300222 [2]港口岩土工程技术交通行业重点实验室,天津300222 [3]天津市港口岩土工程技术重点实验室,天津300222 [4]广东省公路建设有限公司,广东中山528400

出　　处：《岩土工程学报》2022年第5期820-826,共7页Chinese Journal of Geotechnical Engineering

基　　金：广东省重点领域研发计划资助项目(2019B111105002)。

摘　　要：挤密砂桩作为深水原位处理地基新技术在港珠澳大桥和深中通道工程中得到了大量应用。对挤密砂桩复合地基水下原位载荷试验测试的桩土应力分布情况进行分析,在加载过程中实测桩土应力比始终维持为6左右。对大面积水下堆载过程中的复合地基沉降进行了现场实测,对实测资料进行了统计分析,与现有的理论计算方法进行了比较,认为现有普遍应用的日本规范推荐算法,在置换率低于50%时,其计算结果相对实测值偏大,当置换率高于50%时,该方法不再适用。提出了基于实测的挤密砂桩沉降修正计算方法,并建议桩土应力比取值范围为5~6.3。The sand compaction pile which is an efficient foundation treatment method under water is used in Hongkong-Zhuhai-Macao Bridge and Shenzhen-Zhongshan Link. A large number of in-situ tests such as underwater plate load tests and surcharge preloading tests under water are implemented. The in-situ values of pile-soil stress ratio in the underwater plate load tests are discussed, and the values of pile-soil stress ratio are kept to 6 in the process of loading. The settlement of the sand compaction pile ground in the process of surcharge preloading under water is monitored, and the values of settlement are comparatively analyzed to those by the available calculation method recommended in the Japanese standard. It is illustrated that the available calculation method in the Japanese standard is conservative when the replacement rate is less than 50%, and is not suitable for the practice when the replacement rate is more than or equal to 50%. A modified settlement calculation method based on the in-situ measurement is proposed and illustrated, and the values of pile-soil stress ratio are suggested in the range of 5 to 6.3.

关 键 词：挤密砂桩 沉降算法 桩土应力比 现场实测 沉降折减比 

分 类 号：TU43[建筑科学—岩土工程]