水泥品种对水泥基材料热膨胀性能影响的研究

针对不同品种水泥基材料在高温下体积稳定性问题,采用差示热膨胀仪对普通硅酸盐水泥、高铝水泥和硫铝酸盐水泥分别制成的水泥石的热膨胀性能进行了测试,并用DTA/TG对影响水泥石高温热性能的原因和机制进行了分析。结果表明：3种水泥石的热膨胀率均随着温度的升高先增加后显著降低,到达一定温度后趋于稳定。分析热膨胀随温度变化的规律获知,3种水泥在高温状态下应用时,高铝水泥体积稳定性最佳、硫铝酸盐水泥次之、普通硅酸盐水泥石最差。水泥石的热膨胀均是由其固相组分的受热膨胀与主要水化产物的脱水收缩共同作用的结果,而水泥品种不同,其水化产物中主要脱水组分截然不同。

Investigation on Behavior of Thermal Expansion of Cementitious Materials

According to volume stability in high temperature of different varieties cementitious materials,the thermal expansions of hardened cement paste of three types of cement（Portland cement,calcium aluminate cement and sulphoaluminate cement） were tested through equipments NETZSCH D/L 402EP,the mechanism were analyzed and quested.the result shows that thermal expansion curve increases at first,then decreases as temperature continued to rise,and finally becomes stable at certain temperature.According to the thermal shrinkage rate and temperature which the thermal expansions becomes stable,we have known the volume stabilization of calcium acuminate cement is best,sulphoaluminate cement is better,and Portland cementis is worst in the high temperature.Thermal Expansion causes by thermal expansion of solid-phase components and syneresis of main hydration product,and main components of dehydration are quite different with cement variety.