上覆硬壳层软土场地的真空预压加固试验研究  

Experimental Study of Challenging Ground with Overlying Crust Improved by Innovative Vacuum Preloading Method

作　　者：王征亮[1] 何洪涛[1] Wang Zhengliang;He Hongtao(CCCC-FHDI Engineering Co., Ltd., Guangzhou Guangdong 510230, China)

机构地区：[1]中交第四航务工程勘察设计院有限公司

出　　处：《港工技术》2019年第B06期132-137,共6页Port Engineering Technology

摘　　要：针对上覆硬壳层下卧深厚软土地基的复杂场地,选取代表性场地作为试验区采用浅层引孔结合开挖换填的真空预压新技术地基处理方案。通过试验区表层沉降、分层沉降、孔隙水压力的监测,研究了地基沉降和孔隙水压力随时间的变化规律;试验区加固前后采用静力触探和十字板剪切等原位试验、现场取土进行室内土工试验,对比分析了土体在加固前后物理力学指标的变化;试验区加固土体经过排水固结,土体的压缩性降低、强度指标提高,物理力学性质得到非常明显的改善,结果表明采用的浅层引孔结合开挖换填的真空预压新技术处理上覆硬壳层复杂场地是成功的。In view of the complex site with hard crust overlying and deep soft soil underlying, the representative site is selected as the test area to adopt the new vacuum preloading technology of shallow hole-leading combined with excavation and filling. Based on the monitoring of surface settlement, stratified settlement and pore water pressure in the test area, the variation law of foundation settlement and pore water pressure with time is studied. In-situ tests such as static cone penetration test and cross shear test were conducted before and after reinforcement in the test area, and in-situ soil samples were taken for indoor geotechnical tests. The changes of physical and mechanical indexes of soil before and after reinforcement were compared and analyzed. After drainage consolidation, the compressibility of soil was reduced, the strength index was improved, and the physical and mechanical properties were obviously improved in the test area. The new vacuum preloading technology combined with hole excavation and filling replacement is successful in treating complex site with overlying hard shell.

关 键 词：上覆硬壳层 软土地基 复杂场地 浅层引孔 开挖换填 真空预压 

分 类 号：TU447[建筑科学—岩土工程]