围海造地软基加固试验研究-《郑州大学学报(工学版)》

文章信息/Info

作者:: 朱群峰; 赵士文; 杨守华; 等.; 南京水利科学研究院岩土工程研究所,江苏南京,210024, 南京瑞迪建设科技有限公司水科院勘测设计院,江苏南京,210029

Author(s):: ZHU Qunfeng; ZHAO Shiwen; YANG Shouhua; etc;; 1. Geotechnical Engineering Department of Nanjing Hydraulie Research Institute, Nanjing 210024, China; 2. Design and Consulting Department of Nanjing R&D Tech Group Co. Ltd., Nanjing 210029, China

Keywords:: dredger fill; degree of vacuum ; post-construction settlement; bearing capacity; geotechnical water box

摘要:: 围海造地形成的吹填淤泥地基具有含水率高、压缩性高、强度极低等特点,对工程使用极其不利,必须进行加固处理.结合某工程,采用真空预压法对吹填淤泥地基进行加固,同时布置原观仪器进行现场试验研究.位移监测结果表明试验区实测地表沉降量达1 616 mm,地基加固结束时的平均固结度达86％,工后沉降小于300 mm;水平位移小于10 mm;吹填淤泥单位厚度的压缩量达267 mm/m,属于大变形的范畴；真空度和孔隙水压力监测结果表明真空度在吹填淤泥地基中的传递存在较大的沿程损失;地基加固效果检测结果表明加固后的吹填淤泥平均十字板强度达15.2 kPa;吹填淤泥的土性指标得到了不同程度的改善；地基承载力大于60 kPa;地基加固达到了预期的效果.探讨了真空预压加固吹填淤泥地基存在的问题,建议进一步开发土工水箱来改进吹填淤泥地基加固方法.

Abstract:: The dredger fill of reclamation projects is characterized by high water content, high compressionand low strength, etc. , and it must be reinforced because of its adverse effects on projects, Based on a practi.cal projeet, the dredger fill is consolidated by means of the vacuum preloading method, Field tests are per.formed by arranging in-situ instruments. Aecording to the results of displacement monitoring, the ground sur.face settlement is 1616 mm, the average degree of consolidation may reach 869 at the end of foundation rein-forcement, and the post-construction settlement is less than 300 mm, The horizontal displacement is less than10 mm. The compressive deformation of dredger fill per unit thickness is 267 mm/m, and it belongs to largedeformation. Aecording to the results of degree of vacuum and power water pressure monitoring, the degree ofvacuum which transmits in the dredger fill foundation has larger frictional loss. The average vane strength ofthe dredger fill after construction is 15. 2 kPa. The indices of the dredger fill are improved to some extent, Thebearing capacity of the foundation is more than 60 kPa, and the foundation consolidation is satisfactory. Theexisting problems in consolidating the dredger fill by use of the vacuum preloading method are discussed. lt issuggested that the consolidation method for the dredger fill should be improved by developing the geotechnicalwater Dox.