动静力排水固结法加固淤泥地基的技术及效果

Study on the Strengthen Technique and Results of a Silt Foundation with Static-Dynamic Consolidation Method

目的对广州某工程采用的动静力排水固结法处理淤泥地基的加固技术及加固效果进行研究,以期找到合理的动力工序、参数及排水系统的设置.方法通过实时监测超孔隙水压力、土体分层沉降等指标的结果,原位测试静载荷、十字板剪切、静力触探等的结果,对比加固前后土体物理力学性质指标的结果,检验加固效果;对于深厚淤泥地基加固,采用少击多遍、逐层加固的施工工艺并辅助良好的排水系统.结果油罐区和道路区工后承载力特征值分别达到120 kPa和180 kPa,加固前后淤泥的平均含水量、孔隙比及压缩系数分别降低了26.1%、31.6%和45.2%,密度、黏聚力和内摩擦角分别提高11.3%、27.2%和47.1%.结论静动力排水固结法的成功应用不但降低了成本,也为东南沿海地区类似的软土地基处理工程提供了经验.

In order to find out the reasonable dynamic arrangement, parameters and setting of drainage sys- tems, the strengthen technique and results in a silt ground disposal project of Guangzhou with the method of static-dynamic consolidation were studied. The results of extra pore water pressure, settlement of different depth, load test, field vane strength test, cone penetration test, physico-mechanical properties before and after treatment was used to test the result of treatment. Better result was obtained by increasing the number of pas- ses with corresponding decrease in the number of tamping in each pass with a system of horizontal drainage and vertical plastic strip drains,the beating capacity in oil tank area and road area improved to 120kPa and 180kPa. The average water content, void ration and coefficient of compressibility decreased by 26. 1%, 31.6% and 45.2% ,bulk unit weight,cohesion and friction angle increased by 11.3% ,27.2% and 47. 1%. The successful application of dynamic-static consolidation method was not only decrease the cost but also provide success experiences for similar soft soil improvement projects in southern east area.