摘要
为节约水泥资源,响应“双碳”目标,本文探究以工业固废赤泥和钢渣粉与水泥复合固化流态土,对不同赤泥和钢渣粉掺量下流态固化土的工作性能、抗压强度、电化学阻抗谱和微观结构进行试验研究。结果表明,改变赤泥-钢渣粉掺量可以调控流态固化土工作性能,坍落度随赤泥掺量的增大呈先增大后减小的趋势,赤泥掺量为10%(质量分数)时,坍落度达到最大值,为203.0 mm,凝结硬化时间随赤泥掺量的增大逐渐缩短,初凝时间为250~285 min。流态固化土的抗压强度主要由水化反应生成的水化硅酸钙(C-S-H)凝胶和钙矾石构成,赤泥掺量为20%(质量分数)时,28 d龄期的抗压强度达到最大值,为4.67 MPa,赤泥和钢渣粉存在协同作用,复掺赤泥和钢渣粉使C-S-H凝胶的生成量增加,流态固化土的力学性能得到了提升。随着赤泥掺量的增大,容抗弧半径、阻抗模值和相位角峰值、孔溶液电阻R_(e)和凝胶中双电层电容Q均呈先增大后减小的趋势,当赤泥、钢渣粉和水泥的质量比为2∶3∶5时均达到最大值,电化学阻抗谱及其等效电路拟合结果与抗压强度变化规律一致,电化学阻抗谱技术用于流态土固化效果的无损测试具有可行性。
In order to save cement resources and respond to the goal of“double carbon”,the use of industrial solid waste red mud and steel slag powder combined with cement to solidified fluid soil were explored.The working performance,compressive strength,electrochemical impedance spectroscopy and microstructure of the fluidized solidified soil with different red mud and steel slag powder content were investigated.The results show that the working performance of fluidized solidified soil can be regulated by changing the red mud and steel slag powder content.The slump increases first and then decreases with the increase of red mud content,when the red mud content is 10%(mass fraction),the slump reaches the maximum value of 203.0 mm.The setting and hardening time decreases with the increase of red mud content,the initial setting time ranges from 250 to 285 min.The compressive strength of fluidized solidified soil is mainly composed of hydrate calcium silicate(C-S-H)gel and ettringite generated by hydration reaction.At the age of 28 d,the compressive strength reaches the maximum value of 4.67 MPa,when the red mud content is 20%(mass fraction).There is a synergistic effect between red mud and steel slag powder,the addition of red mud and steel slag powder increases the production of C-S-H gel,and improves the mechanical properties of fluidized solidified soil.With the increase of red mud content,the arc radius of capacitive reactance,impedance modulus and phase angle peak,pore solution resistance R_( e )and double electric layer capacitance Q all increase first and then decrease,and they all reach the maximum value when the mass ratio of red mud,steel slag powder and cement is 2∶3∶5.The results of electrochemical impedance spectrum and its equivalent circuit fitting are consistent with the variation law of compressive strength,electrochemical impedance spectrum technology is feasible in non-destructive testing of curing effect of fluidized solidified soil.
作者
王聪聪
刘茂青
宋红旗
庚利民
杜红秀
WANG Congcong;LIU Maoqing;SONG Hongqi;GENG Limin;DU Hongxiu(College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanxi Sixth Construction Group Co.,Ltd.,Taiyuan 030024,China)
出处
《硅酸盐通报》
CAS
北大核心
2023年第7期2488-2496,共9页
Bulletin of the Chinese Ceramic Society
基金
横向科研基金资助项目(RH2100004072)。
关键词
流态固化土
赤泥
钢渣粉
工作性能
抗压强度
电化学阻抗谱
fluidized solidified soil
red mud
steel slag powder
working performance
compressive strength
electrochemical impedance spectroscopy
