阳离子乳化沥青对硅酸盐水泥砂浆力学性能影响分析

Mechanism and Influence of Asphalt Emulsion on Mechanical Performance of Cement Mortar

针对乳化沥青掺量对水泥砂浆力学性能的影响,采用不同质量百分比的乳化沥青与水泥(AE/C)制备乳化沥青改性水泥砂浆,测试其抗压强度和抗折强度等力学性能,并采用扫描电镜(SEM)分析微观结构,解析乳化沥青对水泥砂浆力学性能影响机理.结果表明:乳化沥青含量大于5%时,砂浆的抗压强度显著下降,抗折强度提高;当含量达10%时,砂浆的韧性最佳.乳化沥青对水泥砂浆力学性能的改善机理为沥青胶浆填充在水化产物的空隙中,起到吸收荷载、为水化产物失稳破坏提供缓冲的作用.当沥青用量过大时,沥青膜厚度大于水化硅酸钙(C-S-H)长度,水化产物未穿过沥青膜生长,无法形成连续的网络结构,导致砂浆韧性降低.

This paper is intended to analyze the influence of dosages of asphalt emulsion on the mechanical performance of cement mortar. Different mass percentages of asphalt emulsion and cement （AE/C） were ap- plied to make asphalt emulsion cement mortar. The compressive strength and flexural strength of asphalt emul- sion cement mortar were tested. Finally, mechanism of asphalt emulsion on mechanical performance of cement mortar was analyzed by scanning the microscopic structures using scanning electron microscope （SEM）. The results show that when the content of asphalt emulsion is more than 5% , compressive strength of the mortar decreases significantly while the flexural strength increases. When AE/C comprises 10% , the mortar shows the greatest toughness. Asphalt emulsion dosage is a main factor that affects the mechanical performance of ce- ment mortar. When the thickness of asphalt film is larger than the length of hydrated calcium silicate （C - S - H） , cement hydration products neither grow through the asphalt membrane nor form a continuous network structure, which leads to lower toughness of the cement mortar.