养护温度对碱渣-矿渣-电石渣固化淤泥强度性质的影响机制  

Influencing mechanism of curing temperature on strength properties of silt solidified with soda residue,ground granulated blast furnace slag and carbide slag

作　　者：何俊 吕晓龙 朱元军 HE Jun;LYU Xiaolong;ZHU Yuanjun(School of Civil,Architectural and Environment,Hubei University of Technology,Wuhan 430068,China)

机构地区：[1]湖北工业大学土木建筑与环境学院,湖北武汉430068

出　　处：《水利水电科技进展》2023年第5期58-65,共8页Advances in Science and Technology of Water Resources

基　　金：国家自然科学基金项目(41772332)。

摘　　要：为揭示养护温度对固化疏浚淤泥强度性质的影响机制,利用碱渣、矿渣、电石渣进行疏浚淤泥固化处理,开展无侧限抗压强度(UCS)、加州承载比(CBR)和三轴压缩等试验研究固化淤泥强度性质,并结合X射线衍射和扫描电镜测试探讨养护温度对固化淤泥的作用机理。结果表明:固化淤泥UCS与养护温度之间可用指数函数描述,当养护温度从35℃升高至50℃时UCS大幅提升,50℃与20℃固化淤泥UCS之比为2.4~6.8,养护温度和龄期对低含水率固化淤泥强度的影响更为显著;对于初始含水率为44%的固化淤泥,养护温度升高时CBR随养护龄期的增幅显著,其值满足高速公路和一级公路路基填料的最小CBR要求;当养护温度从20℃升高至50℃时,固化淤泥应力-应变曲线由软化型变为硬化型,50℃与20℃时固化淤泥黏聚力之比为3.8~8.4,内摩擦角之比为1.1~1.2;随着养护温度的升高,水化氯铝酸钙和水化硅酸钙等产物增多,颗粒团聚现象更显著,从而提升固化淤泥的强度。To reveal the influencing mechanism of curing temperature on the strength properties of solidified dredged silt,the dredged silt was solidified with soda residue,ground granulated blast furnace slag and carbide slag.Unconfined compressive strength(UCS),California bearing ratio(CBR)and triaxial compressive tests were conducted to investigate the strength properties of solidified silt.The microstructural mechanism was discussed based on X-ray diffraction and scanning electron microscopy.The results show that the relationship between the UCS of solidified silt and curing temperature can be described by an exponential function.The UCS of solidified silt increases significantly when the curing temperature increases from 35℃to 50℃and the UCS ratio between 50℃and 20℃varies from 2.4 to 6.8.The curing temperature and time have more significant influence on the strength of solidified silt with low water content.For the solidified silt with an initial water content of 44%,the increase of CBR with curing time is significant at high curing temperature,and its value meets the minimum CBR requirement for highway and primary road base.When the curing temperature increases from 20℃to 50℃,the stress-strain curve of the solidified silt changes from strain-softening to strain-hardening.The ratio of cohesion for the solidified silt at 50℃to 20℃varies from 3.8 to 8.4,and the friction angle ratio varies from 1.1 to 1.2.With the increase of curing temperature,the hydration products such as calcium chloroaluminate hydrates and calcium silicate hydrate increase,and the particle agglomeration phenomenon is more significant,leading to the strength increase of the solidified dredged silt.

关 键 词：养护温度 疏浚淤泥 碱渣 矿渣 强度 微观结构 

分 类 号：TU411[建筑科学—岩土工程]