基于乳化沥青pH值对ξ电位的影响,研究了乳化沥青pH值对CA砂浆流动度、可工作时间、分离度、含气量、表观密度及浆体体系pH值的影响.结果表明:乳化沥青pH值在2.5～9.5时,CA砂浆流动度处于稳定状态；pH＜2.5,pH＞9.5时,CA砂浆流动度均增加,且后者增加显著；pH=11.5时,其流动度达到最高；pH=9.5时,60 min后CA砂浆流动度经时损失最大,达到26.09％.pH=2.5时,CA砂浆表观密度随时间的延长逐渐减小；pH=9.5时,CA砂浆表观密度随时间的延长而增大.pH=1.5,9.5时,CA砂浆的分离度最小.乳化沥青pH值对CA砂浆浆体体系pH值的影响不大.为提高CA砂浆的综合性能,乳化沥青的合适pH值为1.5或9.5.%Influence of pH value of emulsified asphalt on work performance of CA mortar was studied by measuring the effect of pH on zeta potential. Results show that the pH of emulsified asphalt has great influence on the fluidity, working time, separating degree, air content and apparent density and pH of CA mortar, which results in the influence of pH of emulsified asphalt on zeta potential. When pH = 2. 5 -9. 5, the fluidity of CA mortar keeps in a stable level, while pH＜2. 5, the fluidity increases, and it increases significantly when pH＞9. 5, the fluidity reaches a maximum value when pH = ll. 5. The loss of fluidity with time reaches to 26. 09% when pH = 9. 5. The apparent density decreases with time when pH =2. 5, and it increases when pH = 9. 5. Separating degree has no effect on the symbols of the ζ potential, but it has influence on its absolute value. The bigger the absolute value, the smaller the separating degree and vice versa. When pH = l. 5 and 9. 5, the separating degree was small. pH of asphalt has a little influence on the pH of CA mortar. The appropriate pH of asphalt for CA mortar is 1. 5 or 9. 5.
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