真空联合堆载预压加固处理效果沿深度的分布规律研究  

Distribution law of reinforcement effect of vacuum combined urcharge preloading along depth

作　　者：肖时辉 王虎 周岳 李胜伟 李伟鹏 周波 Xiao Shihui;Wang Hu;Zhou Yue;Li Shengwei;Li Weipeng;Zhou Bo(Zhuhai Da Heng Qin Company Limitied,Zhuhai 510089,China;Zhuhai Institute of Urban Planning&Design,Zhuhai 518037,China;CRCC Hatbour and Channel Engineering BureauGroupCo.Ltd,Zhuhai 510089,China)

机构地区：[1]珠海大横琴股份有限公司,广东珠海510089 [2]珠海市规划设计研究院,广东珠海518037 [3]中国铁建港航局集团有限公司,广东珠海510089

出　　处：《建筑科学》2023年第11期159-165,共7页Building Science

基　　金：住房和城乡建设部科技示范项目(2021-S-058);广东省住房和城乡建设厅科技创新计划项目(2022-K4-231814);珠海市科技计划项目(ZH22036204200009PWC)。

摘　　要：真空联合堆载预压法作为一种大面积深厚软土常用处理方法,加固效果受到了广泛关注。为研究真空联合堆载预压加固处理效果和处理后软土层物理力学性能沿深度的分布规律,通过不同深度处试样的室内土工试验和原位测试获得处理前后软土的物理力学指标和原位力学性能,系统对比分析了处理后物性、力学参数沿深度的变化和分布规律。结果表明:真空联合堆载预压法加固效果随深度递减,对路基填土层底下15m处土体物性参数的改善仅为5%左右;表征黏性土稠度状态的液性指数在未处理深厚淤泥层中沿深度方向呈现递减规律,处理后不同深度处液性指数稳定在1.2,液性指数与淤泥层加固效果密切相关,可作为判断排水固结法对土体加固是否有效的重要依据;处理后深厚淤泥层物理力学参数沿深度分布趋于一致,为均匀土层。As a common treatment method of large-area and deep soft foundation,the reinforcement effect of vacuum combined surcharge preloading method has attracted extensive attention.In order to study the distribution law of physical and mechanical properties of deep soft soil along the depth after vacuum combined surcharge preloading treatment,the physical and mechanical indexes and in-situ mechanical properties of soft soil before and after reinforcement treatment are comprehensively compared through the indoor geotechnical test and in-situ test system of soft soil at different depths,and the distribution law of strength and deformation parameters of soft soil along the depth after treatment is analyzed.The results show that:The consolidation effect of vacuum combined with surcharge preloading method decreases with the depth,and the improvement of physical parameters of soil at 15m depth is about 5%;The liquid index representing the consistency state of cohesive soil shows a decreasing law along the depth direction in the untreated deep silt layer.After treatment,the liquid index at different depths is stable at 1.2.There is an upper limit value for the influence of vacuum surcharge preloading method on the liquid index of soft soil;After treatment,the distribution of strength and deformation parameters of deep silt layer along the depth tends to be consistent,which can be considered as a homogeneous soil layer.

关 键 词：深厚软土 排水固结 加固效果 物性参数 力学参数 

分 类 号：TU47[建筑科学—结构工程]