多通道负压排水动力夯实技术试验

应用多通道组合低位负压动力夯实法对南通滨海园区通州湾科教城场地进行加固地基研究,分析水位、表面沉降、土体深层水平位移、孔隙水压力、真空度的变化过程和特性,对处理后地基土的物理性质、强度和承载力进行了检测和评价。结果表明,持续降雨下场地内水位可快速降至3 m以下,非密封条件下抽真空在7 m深度内形成负压,强夯引起的超静孔压可在2~3 d内快速消散;夯实以沉降压缩为主,侧向位移小,土体物理力学性质明显改善,有效影响深度达到6.5 m,地基承载力特征值达到80 k Pa;多通道负压排水动力夯实技术能够增强降排水和超静孔压连续快速消散能力,对地下水丰富、降雨充沛区域的适应性强。

Experimental study of new technology of multi-channel vacuum drainage dynamic compaction

The multi-channel combined with low negative pressure dynamic compaction method was used to reinforce the ground in the Tongzhou Bay Science and Entrepreneurship Town in the coastal zone of Nantong. The change process and characteristics of ground water level, surface settlement, horizontal displacement of deep soil, pore water pressure, and vacuum degree were analyzed. The main physical properties, soil strength, and bearing capacity of the treated foundation were tested and evaluated. The results show that, the underground water level in the field can quickly drop to less than 3 m under the condition of continuous rainfall, a negative pressure condition was formed within a depth of 7 m using the vacuum method under the non-seal condition, and super static pore pressure caused by dynamic compaction can rapidly dissipate in 2 to 3 days. Influence of dynamic compaction was mainly based on settlement compression, the lateral displacement was small, and the physical and mechanical properties of soil were improved significantly, with the effective depth reaching 6. 5 m and the characteristic value of bearing capacity of foundation reaching 80 kPa. The new technology can enhance the ability of water drainage and the rapid dissipation of super static pore pressure. It is worth popularizing and applying in areas of abundant groundwater and rainfall.