岩土力学
巖土力學
암토역학
Rock and Soil Mechanics
2015年
11期
3187-3192
,共6页
疏浚淤泥%真空负载%多孔介质%渗流
疏浚淤泥%真空負載%多孔介質%滲流
소준어니%진공부재%다공개질%삼류
dredged sludge%vacuum load%porous media%seepage
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。
採用自主改裝的變壓頭黏土滲透儀,模擬疏浚淤泥脫水過程中水分在淤泥顆粒多孔介質中的遷移運動過程,通過測定疏浚淤泥脫水過程中滲透繫數與過濾常數、滲水量與濾液量、泥餅含水率與孔隙率,探究瞭負載壓力為100 kPa時,不同負載方式(負載時間及負載壓力梯度變化)對疏浚淤泥脫水過程中過濾和滲流規律的影響。研究髮現:負載下的過濾和滲流同時進行,負載1 h期間,前期0~40 min內過濾佔主導地位,後期40~60 min內滲流起關鍵作用。負載壓力梯度由原來1 h內間隔變化1次,變為以20 kPa為梯度遞增變化5次,隨著壓力變化梯度減小,滲透繫數、過濾常數增加,淤泥脫水性能得到較明顯的改善,併且前期負載壓力越小,脫水效果越好。
채용자주개장적변압두점토삼투의,모의소준어니탈수과정중수분재어니과립다공개질중적천이운동과정,통과측정소준어니탈수과정중삼투계수여과려상수、삼수량여려액량、니병함수솔여공극솔,탐구료부재압력위100 kPa시,불동부재방식(부재시간급부재압력제도변화)대소준어니탈수과정중과려화삼류규률적영향。연구발현:부재하적과려화삼류동시진행,부재1 h기간,전기0~40 min내과려점주도지위,후기40~60 min내삼류기관건작용。부재압력제도유원래1 h내간격변화1차,변위이20 kPa위제도체증변화5차,수착압력변화제도감소,삼투계수、과려상수증가,어니탈수성능득도교명현적개선,병차전기부재압력월소,탈수효과월호。
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.