考虑盐度影响的粉煤灰固化软土直剪试验  

Direct shear test of fly ash-stabilized soft soil with considering salinity effect

作　　者：殷杰[1] 邱文杰 田雪晨 YIN Jie;QIU Wenjie;TIAN Xuechen(Faculty of Civil Engineering and Mechanics,Jiangsu University,Zhenjiang,Jiangsu 212013,China)

机构地区：[1]江苏大学土木工程与力学学院,江苏镇江212013

出　　处：《江苏大学学报（自然科学版）》2025年第1期120-124,共5页Journal of Jiangsu University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51978315)。

摘　　要：采用粉煤灰作为固化剂,制备了多组粉煤灰固化软土试样,其孔隙水中盐度分别为0%、2%、4%和6%,养护龄期分别为3 h、7 d和28 d.通过开展室内直剪试验,探讨盐度对粉煤灰固化软土强度特性的影响.试验结果表明:竖向固结压力为50 kPa时,粉煤灰固化软土的剪应力与剪切位移关系曲线呈现软化型,而在竖向固结压力为200 kPa时曲线呈现硬化型;高盐度试样具有较低的峰值剪应力和残余强度,表明高盐度对粉煤灰固化软土强度特性具有不利的影响;随着盐度增加,各养护龄期下软土试样的抗剪强度、黏聚力和内摩擦角的曲线均呈现近似线性下降的趋势,主要原因在于盐度的增加抑制了粉煤灰中活性成分的水化反应.Using fly ash as curing agent,the multiple groups of fly ash-stabilized soft soil samples were prepared with pore water salinity levels of respective 0%,2%,4%and 6%and curing times of respective 3 hours,7 days and 28 days.Through laboratory direct shear tests,the influence of salinity on the strength characteristics of fly ash-stabilized soft soil was investigated.The test results show that at the vertical consolidation pressure of 50 kPa,the relationship curve between shear stress and shear displacement of the fly ash-stabilized soft soil exhibits softening behavior,while at the vertical consolidation pressure of 200 kPa,the curve shows hardening behavior.The high salinity samples exhibit lower peak shear stress and residual strength,which indicates that high salinity has adverse effect on the strength characteristics of the fly ash-stabilized soft soil.As the salinity is increased,the shear strength,cohesion and internal friction angle of soft soil samples at all curing times show approximately linear decreasing trend,which is mainly due to the inhibition of hydration reaction of the active components in the fly ash caused by the increased salinity.

关 键 词：粉煤灰 软土 固化剂 盐度 养护龄期 室内直剪试验 

分 类 号：TU411[建筑科学—岩土工程]