脱硫石膏晶须对水泥基材增强行为的研究

以合成脱硫石膏晶须为增强、增韧剂,以水泥砂浆为研究对象,检测了脱硫石膏晶须掺量 (占水泥质量百分比为:0、0.5wt%、1wt%、2wt%、3wt%)对水泥砂浆试件不同龄期(3 d、7 d、28 d)抗压、抗折强度的影响;通过脱硫石膏晶须在碱性水泥基质中的分布和微观形貌的分析,进一步探讨了脱硫石膏晶须添加水泥基材的增强、增韧机理.结果表明:添加1wt%脱硫石膏晶须的水泥砂浆试件的抗折、抗压强度比未添加晶须试件的分别提高了28.41%、45.65%;脱硫石膏晶须在水泥砂浆试件中能保持原有形貌而稳定存在;脱硫石膏晶须在水泥基质中微缝处具有的架桥、连接作用阻碍了水泥基质中微裂纹的产生与扩展,从而提高了水泥砂浆试件的抗折、抗压强度.

Enhancement Performance of Desulfuration Gypsum Whisker on Cementitious Materials

Mortar samples were prepared by using different desulfuration gypsum whisker(0,0.5wt%,1wt%,2wt%,3wt%) as toughening agent.The samples' mechanical properties at different ages(3 d,7 d,28 d), microstructure of gypsum whisker and it distribution in cement matrix were detected.It was found that the flexural strength and compression strength of sample added with 1wt% desulfuration gypsum whisker were increased by 28.41% and 45.65%, respectively.The mechanisms of the reinforcement of desulfuration gypsum whisker on cement were also discussed, the mechanical improvement can be explained by the energy-dissipating processes owing to crack bridging, crack deflection, and whisker pull-out at the crack tips.