摘要
结合广州南沙泰山石化成品油库区大面积深厚淤泥软土地基加固处理工程,探讨动力排水固结法处理高含水率、大孔隙比淤泥地基的基本原理、设计参数和施工工艺。对不同区域的孔隙水压力、土压力、分层沉降进行监测,利用标准贯入试验、十字板剪切试验、静力触探试验和载荷试验等原位测试手段对施工过程和加固效果进行检测。根据现场试验数据,分析动荷载作用下淤泥质土的孔隙水压力、土压力和土体沉降的发展规律。测试结果表明:土压力变化、土体沉降与孔隙水压力的变化具有很好的相关性,随着孔隙水压力的消散,土的抗剪强度不断提高,工后沉降大大降低,土体达到超固结状态。研究表明,"动静结合,先轻后重,逐级加能,少击多遍,逐层加固"的施工工艺,结合空间网状排水体系(由水平排水体+竖向塑料排水板+土体微裂隙排水系统组成),对处理大面积深厚淤泥质软土地基加固效果明显,土体的物理力学性能大大改善,各项指标均能达到或超过设计要求,该法在地基处理工程中具有良好的应用前景。
Based on silt ground treatment project of Taishan petrifaction storage area of Nansha,Guangzhou,the basic principle,design parameters and construction technology of dynamic drainage consolidation method（DDCM） for improving the mud ground with high water content and large void ratio are discussed. By using field test methods,the pore water pressure,the soil pressure and the layered settlement are measured;the standard penetration test,vane shear test,static cone penetration test and the load experiment have been used to monitor and test the construction process and consolidation effect. According to the experimental data,the laws of pore water pressure,soil pressure and settlement of soft soils under dynamic loading are analyzed. The test results show the correlation among the variation in vertical settlement,soil pressure and excess pore water pressure is significant. With the dissipation of pore water pressure,the shear strength of soil improves and the post-construction settlement reduces,and the soils reach over-consolidated state. The research results reveal that it is obvious to treatment the large area of deep and thick silt foundation with the new construction technology of ＂static-dynamic combination,the tamping is light first and then becomes larger with energy adds gradually,fewer time and more cycles,consolidation by layer＂;combining mesh drainage system which is composed of the horizontal drainage body,the plastic vertical drainage board and micro-fracture system of soils,the physico-mechanical properties are improved obviously,and physico-mechanical properties are better than expected. DDCM has extensive perspectives for soft ground improvement engineering.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第A02期4000-4007,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
广东省自然科学基金资助项目(6021462)
广东工业大学博士基金资助项目(09033)
关键词
土力学
动力排水固结法
软土地基处理
监测与检测
施工工艺
孔隙水压力
soil mechanics
dynamic drainage consolidation method（DDCM）
soft ground treatment
monitoring and testing
construction technology
pore water pressure
