钢渣粉-水泥复合体系水化热及动力学研究

Heat Evolution and Hydration Kinetics of Steel Slag Powder-Cement Composite Binder

为了研究钢渣粉对水泥水化的影响,通过水化热和水化动力学模拟,研究了钢渣粉掺量及细度对水泥早期水化进程及反应机理的影响。结果表明:与纯水泥相比,细钢渣粉缩短诱导期,粗钢渣粉延长诱导期;细钢渣掺量为15%时,加速期缩短,细钢渣掺量超过15%时,加速期延长;钢渣比表面积增大或掺量增加,第3放热峰提前;总放热量随钢渣掺量增加而降低,随比表面积增大而提高;结晶成核与晶体生长控制加速期,钢渣粉掺入会降低反应阻力,且反应阻力随着钢渣粉掺量的增加,先降低后略微增大;粗钢渣粉-水泥复合体系的反应阻力大于细钢渣粉-水泥复合体系;稳定期反应进程受扩散控制,扩散阻力随着掺量增加先增大后降低;钢渣粉比表面积增大,扩散阻力增大。研究成果为钢渣粉-水泥复合体系水化动力学进一步的研究提供了基础。

A kinetic study by heat evolution is reported to research the influences of the dosages and fineness of steel slag powder on the hydration process and mechanism of cement.Results demonstrate that fine steel slag powder shortens the induction period;on the contrary,coarse steel slag powder delays the induction period.The acceleration period shortens in the presence of 15%dosage of steel slag powder,while elongates when the content of steel slag powder exceeds 15%.Increasing the specific surface area or dosage of steel slag powder brings forward the third exothermic peak.The total heat release declines with the increase of steel slag powder content;but climbs with the increase of specific surface area.The acceleration period is controlled by the nucleation kinetics.In the acceleration period,steel slag powder would cut the reaction resistance;but with the increasing of steel slag powder content,reaction resistance rebounds slightly.Moreover,the reduction of fineness also boosts the reaction resistance.Decay period is controlled by diffusion;diffusion resistance increases and then decreases with the increasing of steel slag powder,and increases with the increasing of specific surface area.The research findings lay a foundation for further studies on the hydration heat and hydrokinetics of steel slag powder-cement composite material.