摘要
采用自主改装的变压头黏土渗透仪,模拟疏浚淤泥脱水过程中水分在淤泥颗粒多孔介质中的迁移运动过程,通过测定疏浚淤泥脱水过程中渗透系数与过滤常数、渗水量与滤液量、泥饼含水率与孔隙率,探究了负载压力为100 kPa时,不同负载方式（负载时间及负载压力梯度变化）对疏浚淤泥脱水过程中过滤和渗流规律的影响。研究发现：负载下的过滤和渗流同时进行,负载1 h期间,前期0-40 min内过滤占主导地位,后期40-60 min内渗流起关键作用。负载压力梯度由原来1 h内间隔变化1次,变为以20 kPa为梯度递增变化5次,随着压力变化梯度减小,渗透系数、过滤常数增加,淤泥脱水性能得到较明显的改善,并且前期负载压力越小,脱水效果越好。
An improved variable-water head permeameter is used to simulate the water migration in dredged sludge during the dewatering process. By determining the permeability coefficient and the filtration constant, the seepage volume and the filtrate volume, the water content and the porosity of the mud cake, the influences of different vacuum loading methods （with different durations and loading gradients） are examined on the filtration and seepage of the dredged sludge during the dewatering process under the vacuum load level of 100 kPa. It is found that the filtration and seepage occur simultaneously under the vacuum loading condition. During the 1 h loading, the filtration prevails for 40 minutes, whereas the seepage dominates in the following 20 min. When the vacuum loading gradient increases from 1 time/ 1 h （gradient： 100 kPa） to 5 times/ 1h （gradient： 20 kPa）, as the vacuum loading gradient decreases, the permeability coefficient and filtration constant increase, and the dehydration of dredged sludge is significant. The smaller the vacuum loading in the early stage is, the more effective the dehydration is.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2015年第11期3187-3192,共6页
Rock and Soil Mechanics
