石膏掺量对硫铝酸钙改性硅酸盐水泥性能影响

The Effect of Gypsum Admixture on Properties of Sulphoaluminate Modified Portland Cement

研究了石膏掺量对硫铝酸钙改性硅酸盐水泥(SMP)物理力学性能、凝结硬化、体积稳定性等影响,并借助XRD、SEM等测试技术手段研究分析了其机理。结果表明,混合材种类不同,石膏掺量对SMP水泥强度影响程度则不同。即水泥中SO3由4%增至8%时,不掺混合材的SMP水泥石体积虽存在略大膨胀,但水泥强度仍有较大提高;而掺加矿渣、粉煤灰等混合材后,石膏的掺量至8%时,水泥石存在有害体积膨胀,且尤以掺粉煤灰最为突出。在SMP高硫高碱水化体系中,矿渣、粉煤灰对水泥石力学性能、体积膨胀性、水化产物结构及发展的影响存在较大差异,应根据混合材种类对SMP水泥中石膏掺量进行合理控制,以利于其合理应用。

Research on the effect of gypsum admixture on properties of sulphoaluminate modified Portland Cement（SMP）,such as physics and mechanics,hardening,volume stability.Testing technology research and analysis of its mechanism was analyzed by XRD,SEM etc.Research results show that with the admixture of gypsum increase（SO3 increased by 4% to 8%）,if without cement additive,SMP strength would improve,the volume would become larger,but no damage.But mixing slag and fly ash,strength decreased.And if gypsum admixture increases to a certain degree,cement may exist harmful volume expansion of the potential threat,especially when mixed fly ash.In the system of high sulphate and high alkali SMP,when adding slag and fly ash,there is big difference on mechanical properties of cement hydration expansion,volume,product structure and development.So gypsum admixture should be reasonably controlled according to different type of cement additive,thus will be helpful to its properly used.