关键词: 水泥砂浆;增稠剂;力学性能;孔结构;电阻率;

Abstract: In order to explore the influence of thickener on performance of air-entrained cement mortar, Arabic gum and xanthan gum were used to compare and analyze the flexural strength, compressive strength, air pore content and pore structure of cement mortar with the same air content under different dosage of thickener. Electrodeless resistivity method was used to continuously monitor the whole process of early hydration of cement mortor before and after adding thickener at the same water-cement ratio, and the mechanism of thickener on the performance of air-entrained cement mortar was discussed. The results showed that an appropriate amount of thickener can improve the mechanical properties of air-entrained cement mortar, but too much thickener would make the mortar strength deteriorate. The addition of thickener made it more difficult to entrained bubbles into the fresh mixed cement mortar system, but it could reduce the air bubbles loss in the process from bubbles to pores, and increase the air pore content of the hardened air-entrained cement mortar. The pore structure of air-entrained cement mortar could be optimized with a certain dosage of thickener. The influence of thickener on the hydration process of cement was the fundamental reason for the different effects of thickener on performance of cement mortar.

Key words: cement mortar; thickener; mechanical property; pore structure; resistivity