摘要
为解决传统水泥固化土存在高能耗、高碳排、高成本等问题,采用NaOH激发高炉矿渣(GGBS)和粉煤灰(FA)基地质聚合物对黏土质砂进行固化。通过开展无侧限抗压强度(UCS)试验,探究了高炉矿渣与粉煤灰比例、碱激发剂掺量、养护龄期、压实度、固化剂掺量对力学性能的影响;结合扫描电镜试验(SEM)和能谱分析(EDS),分析固化土的微观形貌和固化机理。结果表明:不同矿渣粉煤灰比例下存在不同的最优激发剂掺量,当NaOH掺量为5%~7.5%时激发效果较好;减少粉煤灰掺量、延长龄期、增大压实度和固化剂掺量,有利于提高固化土无侧限抗压强度;固化土的变形模量约为抗压强度的16.88~32.88倍;矿渣-粉煤灰在土体内部发生水化反应产生的C-S-H等凝胶产物填充于土体孔隙之间,增强了结构整体性,有效提高了固化土的力学性能。
In order to solve the problems of high energy consumption,high carbon emission and high cost of traditional cement solidified soil,the clay sand is cured with NaOH excited blast furnace slag(GGBS)and fly ash(FA)base polymer.By carrying out unconfined compressive strength(UCS)test,the influences of slag to fly ash ratio,alkali initiator content,curing age,compaction degree and curing agent content on mechanical properties are explored.The micro-morphology and curing mechanism of solidified soil are analyzed by scanning electron microscopy(SEM)and energy spectrum analysis(EDS).The results show that there are different optimal activator content under different slag and fly ash ratio,and the excitation effect is better when the content of NaOH is from 5%to 7.5%.The reduction of fly ash content,the extension of age,the increase of compaction degree and the addition of curing agent are conducive to the improvement of unconfined compressive strength of solidified soil.The deformation modulus of solidified soil is about 16.88-32.88 times of compressive strength.The gel products such as C-S-H produced by the hydration reaction of slag and fly ash in the soil are filled between the pores of the soil,which enhances the structural integrity and effectively improves the mechanical properties of the solidified soil.
作者
胡建林
董少辉
周永祥
冷发光
杜修力
HU Jian-lin;DONG Shao-hui;ZHOU Yong-xiang;LENG Fa-guang;DU Xiu-li(College of Civil Engineering,Hebei University of Architecture,Zhangjiakou O75000,China;State Key Laboratory of Bridge Safety and Resilience,Beijing University of Technology,Beijing 100124,China;China Academy of Building Research Co.Ltd.,Beijing 100124,China)
出处
《公路》
北大核心
2025年第12期36-44,共9页
Highway
基金
国家自然科学基金面上项目,项目编号52378213
河北省高等学校科学技术研究项目,项目编号QN2024070。
关键词
路基工程
固化土
高炉矿渣
粉煤灰
抗压强度
变形模量
固化机理
subgrade engineering
solidified soil
blast furnace slag
fly ash
compressive strength
deformation modulus
curing mechanism
