氧化镁质和硫铝酸钙膨胀剂对工程水泥基复合材料性能的影响

本文研究了氧化镁质和硫铝酸钙膨胀剂对工程水泥基复合材料水化产物及微观结构的影响。结果表明:两种膨胀剂均会引起工程水泥基复合材料流动性能、力学性能的下降;掺入氧化镁质膨胀剂使得材料体系中大量生成富镁硅钙石,而掺入硫铝酸钙膨胀剂使得材料体系中钙矾石含量增大,两种水化产物均可以细化材料的孔结构,改善试样的抗氯离子渗透性能,5%(质量分数)掺量下硫铝酸钙膨胀剂试样的孔径比氧化镁质膨胀剂试样的更小,结构更加稳定。

Effects of Magnesia and Calcium Sulfoaluminate Expansive Agents on Properties of Engineered Cementitious Composites

The effects of magnesia and calcium sulphoaluminate expansive agent on hydration products and microstructure of engineered cementitious composites were studied.The results show that the two expansive agents decrease the fluidity and mechanical properties.The addition of magnesia expansion agent makes a large amount of magnesium-rich calcium-silicate in the material system,while the addition of calcium sulfoaluminate expansion agent increases the content of ettringite in the material system.The two hydration products refine the pore structure of the material and improve the impermeability of the samples.The pore diameter of the sample dope with 5%(mass fraction)calcium sulfoaluminate expansion agent is smaller than that with magnesia expansive agent,and the structure of sample with calcium sulfoaluminate expansion agent is more stable.