柠檬酸钠对普通硅酸盐水泥与硫铝酸盐水泥复配体系的性能研究

Performance Impact Study of Sodium Citrateon the Compound System of Ordinary Portland Cement and Sulphoaluminate Cement

本文通过水泥净浆、砂浆试验,研究了柠檬酸钠对普通硅酸盐水泥与硫铝酸盐水泥复配体系净浆的凝结时间、砂浆流动度和拉伸粘结强度、水泥水化产物的影响。研究表明,柠檬酸钠通过抑制铝酸钙、硫铝酸钙的早期水化,延缓复配体系的凝结时间、改善砂浆流动性,柠檬酸钠掺量为1.2%时,初凝时间与终凝时间分别为106 min、118 min,砂浆的流动度达到最大值为157 mm;柠檬酸钠使水泥后期水化更充分,增加钙矾石的生成量,提高砂浆拉伸粘结强度,柠檬酸钠掺入量为1.0%时,砂浆拉伸粘结强度为0.54 MPa。

In the paper, the effects of sodium citrate on the setting time, mortar fluidity and tensile bond strength, cement hydration of compound system paste of ordinary portland cement as well as sulphoaluminate cement system arestudied, throughthe cement paste and mortar test. The study shows that sodium citrate inhibits the early hydration of calcium aluminate and calcium sulphoaluminate, in this way to delay the setting time of the compound system and improve the fluidity of the mortar. When the dosage of sodium citrate is 1.2%, the initial setting time and the final setting time are 106 min and 118 min, respectively, and the fluidity of the mortar reaches a maximum of 157 mm;Sodium citrate has deepened hydration process of the cement in the later stage, Which increases the amount of ettringiteand the tensile bond strength of the mortar. When the dosageof sodium citrate is 1.0%, the tensile bond strength of the mortar is 0.54 MPa.