盐分对橡胶沥青及橡胶沥青混合料高温性能的影响∗

摘要

In order to explore the effect of salt on rubber asphalt and rubber asphalt mixture’high temperature performance,asphalt rubber was handled with different conditions of salinity.The softening point test,fail tem-perature and Viscous component creep stiffness of Gv was used to evaluate the changes in rubber asphalt’high temperature properties,and rutting test was used to evaluate the effects of salinity on high temperature per-formance of rubber asphalt mixture.Test results indicate that Three indicators show that rubber asphalt’high temperature performance is improved,salinity does not adversely affect the high temperature properties of rub-ber asphalt.Under the condition of the same soaking time for 7 days,With the increase of salt concentration, the softening point,fail temperature and Gv values Showed a trend of decrease after the first increase,the maxi-mum increase occurred at a salt concentration of 3%,the high temperature performance of asphalt rubber firstly increased and then decreased.The best high temperature performance was achieved in 3% salt concentration. Under the condition of the same salt concentration of 3%,with increasing immersion time,softening point,fail temperature and Gv values Showed a trend of increase,the high temperature performance of asphalt rubber was gradually increased.After soaking in the four kinds of different concentrations of salt water,dynamic stability of rubber asphalt mixture values appeared reduced in different degree,the high temperature performance be-came bad.%为研究盐分对橡胶沥青胶结料及橡胶沥青混合料高温性能的影响,将橡胶沥青试件在不同浓度的盐水中浸泡不同的时间。通过软化点、fail tempera-ture和蠕变劲度的粘性成分Gv 3个不同指标来评价盐分对橡胶沥青高温性能的影响,通过车辙实验评价盐分对橡胶沥青混合料高温性能的影响。结果表明,3个指标均升高,说明经过盐水浸泡之后的橡胶沥青高温性能都有所提升,盐分条件的存在没有对橡胶沥青胶结料的高温性能造成不利影响。在相同浸泡时间7 d的条件下,随着盐分浓度的增加,软化点、fail tem-perature和Gv 值总体上呈现先增大后减小趋势,升高最大值均出现在盐分浓度为3％时,说明橡胶沥青的高温性能先升高后降低,在3％盐分浓度时达到最佳；在相同浸泡盐分浓度3％的条件下,随着浸泡时间的增加,3个指标呈升高趋势,说明橡胶沥青胶结料的高温性能得到提升。在4种不同浓度的盐水中浸泡后,橡胶沥青混合料的动稳定度值出现了不同程度的降低,混合料高温抗车辙能力变差。