排水抗液化珊瑚礁砂地基碎石桩成桩工艺  

Construction technology of stone column on coral sand strata for drainage liquefaction mitigation

作　　者：梁小丛[1,2] 井阳 周红星 朱明星[1,2] 徐雄 LIANG Xiao-cong;JING Yang;ZHOU Hong-xing;ZHU Ming-xin;XU Xiong(CCCC Fourth Harbor Engineering Institute Co.,Ltd,Guangzhou 510230,China;Guangzhou Harbor Engineer Quality Examination Co.,Ltd,Guangzhou 510230,China;Second Engineering Company of CCCC Fourth Harbor Engineering Institute Co.,Ltd.,Guangzhou 510230,China)

机构地区：[1]中交四航工程研究院有限公司,广东广州510230 [2]广州港湾工程质量检测有限公司,广东广州510230 [3]中交四航局第二工程有限公司,广东广州510230

出　　处：《水运工程》2022年第3期163-170,共8页Port & Waterway Engineering

摘　　要：基于碎石桩排水抗液化设计要求,成桩后桩间土密实度以及任意深度桩径均应满足设计指标要求。为了验证碎石桩设备在珊瑚礁砂地基成桩能力并获取合适工艺控制参数和质量控制流程,设置了现场试验区对比振冲工艺和振管工艺的成桩质量,分析桩间土挤密效果差异性。结果表明:1)在珊瑚礁砂地基,振冲工艺和振管工艺挤密效果差异不大。2)为了确保桩间土挤密效果和成桩质量,振冲工艺应采用分段填料量、反插密实电流和实时桩径图3个指标控制。3)振管工艺应采用分段填料量控制,结合造孔密实电流识别相对松散层。在松散层成桩时采取增加留振时间、提高反插深度并减缓反插速度等措施。Based on the design requirements for drainage and liquefaction mitigation of stone column, the soil densification between columns and the diameter at any depth should meet the design index requirements after construction. In order to verify constructionability of different equipment on coral reef sand strata and obtain suitable process control parameters and quality control procedures, the field trial test has been performed to compare the pile quality of the vibro-flotation process and the vibrating tube process, and to analyze the difference of soil compaction effect between the piles. The results show that: 1)On coral reef sand strata, there is little difference in the compaction effect between the vibro-flotation process and the vibrating tube process. 2)To ensure the compaction effect of soil between piles and the quality of piles, the vibro-flotation process should be controlled by three indicators: the amount of segmented filler, the reverse-insertion compaction current and the real-time pile diameter chart.3)The vibrating tube process should be controlled by the amount of segmented filler, and the relatively loose layer should be identified in combination with the hole-making compaction current. Measures such as increasing the vibration retention time, increasing the reverse-insertion depth and slowing down the reverse-insertion speed are taken when the loose layer is formed into piles.

关 键 词：珊瑚礁砂地基 排水抗液化 振冲碎石桩 振管碎石桩 

分 类 号：TU471[建筑科学—结构工程] U65[建筑科学—土工工程]