分级真空预压法加固淤泥质黏土的试验分析  

An Experimental Analysis of Mucky Clay Strengthened by Stepped Vacuum Preloading

作　　者：张恒 张炯 ZHANG Heng;ZHANG Jiong(School of Civil Engineering and Architecture,Wuyi University,Jiangmen 529020,China)

机构地区：[1]五邑大学土木建筑学院,广东江门529020

出　　处：《五邑大学学报(自然科学版)》2025年第1期1-7,共7页Journal of Wuyi University(Natural Science Edition)

基　　金：五邑大学博士科研启动基金(BSQD2404);五邑大学创新创业基金(2022CX47)。

摘　　要：针对真空预压法处理细微颗粒含量高的黏土效果差的问题,开展了分级真空预压法和常规真空预压法的室内模型试验,从排水量、抗剪强度、颗粒形态等宏微观角度分析了分级真空预压法的加固机制与优势.结果表明:高初始真空负压(-80 kPa)会促使细微颗粒向排水管迁移聚集,导致排水通道淤堵,不利于中后期土体排水固结;采用分级真空预压法可以有效减少细微颗粒的迁移,并形成稳定的排水通道,但最终排水固结效果与真空加载方式有关;采用2级加载方式(-40 kPa—-80 kPa)的排水固结效果最好,相较于常规真空预压法,土体排水量提高了17.0%,承载力提高了14.9%,且土颗粒形态更加均匀.Aiming at the problem of poor effect of vacuum preloading method in treating clay with high content of fine particles,laboratory model tests of the fractional vacuum preloading method and the conventional vacuum preloading method were carried out.The strengthening mechanism and advantages of the fractional vacuum preloading method are analyzed from the macro and micro perspectives such as displacement,shear strength and particle morphology.The results show that the high initial vacuum negative pressure(80 kPa-)will promote the migration and aggregation of fine particles to the drainage pipe,resulting in the silting of the drainage channel,which is not conducive to the soil drainage and consolidation in the middle and late period.The fractional vacuum preloading method can effectively reduce the migration of fine particles and form a stable drainage channel,but the final drainage consolidation effect is related to the vacuum loading method.The two-stage loading method(40 kPa--80 kPa-)has the best drainage consolidation effect.Compared with the conventional vacuum preloading method,the soil displacement is increased by 17.0%,the bearing capacity is increased by 14.9%,and the soil particle shape is more uniform.

关 键 词：分级真空预压法 排水固结 抗剪强度 微观结构 颗粒分布 

分 类 号：TU411.93[建筑科学—岩土工程]