淤泥土细观渗透固结实验研究  

Test study on microscopic permeation and consolidation of mud soil

作　　者：张明鸣 李荣玉 张剑 周先齐[3] 

机构地区：[1]中交水运规划设计院深圳有限公司,广东深圳518067 [2]深圳市大铲湾港口投资发展有限公司,广东深圳518032 [3]厦门理工学院土木工程与建筑系,福建厦门361025

出　　处：《水运工程》2011年第4期140-144,共5页Port & Waterway Engineering

摘　　要：吹填淤泥粘粒含量高,细观结构的高孔隙比却表现为宏观的小渗透系数两个矛盾的组合。为了研究吹填土固结问题,对其细观结构及细观渗流本质进行试验研究。以深圳大铲湾吹填淤泥为样本进行了微观试验研究,研究指出：吹填淤泥土为明显絮状结构,孔隙率大,孔洞较多,颗粒边界强结合水水膜明显;地基处理后的淤泥大孔径孔隙明显减少,小孔隙也被堵塞,结构变得更致密;而渗透试验的结果表明其渗透系数在10-7~10-8量级,渗透系数极低,因此不能认为众多贯通孔隙即为渗流通道;通过电场作用下淤泥土的渗透系数试验发现渗透系数随着电压的变化而变化,进而验证淤泥渗透系数受结合水含量和有效孔径控制。A microscopic test study was carried out by taking the mud soil of Shenzhen Dachanwan as the sample.The study reveals that the dredged mud soil is obviously flocculent structure with a high void ratio and multiple holes,as well as an obvious water film of strong bound water at the particle boundary;Large aperture holes of mud after foundation dispose decrease obviously,and the small holes are also jammed,forming a more compact structure;The mud holes are of a great amount and rather big,resulting in a high probability of dewatering passageway connecting by holes.It is indicated from the permeation test that the osmotic coefficients are in the magnitude of 10-7~10-8 and with a low osmotic coefficient.So,if the continuous pores are thought to be the seepage passageway,there is a natural contradiction between the high porosity ratio and low osmotic coefficient;Holes in mud are in the majority of 5 μm and below,especially 2 μm and below.Water in holes is in the majority of weak bound water and capillary water;Osmotic coefficients of mud soil under electric field are changing along with voltage;Osmotic coefficients after foundation dispose are less than that before foundation dispose.Furthermore,the osmotic coefficients of mud under the control of effective aperture and bound water content are checked.

关 键 词：淤泥土 细观 渗透系数 电镜扫描 

分 类 号：TU472.9[建筑科学—结构工程]