经济型低胶粉掺量橡胶沥青混合料路用性能研究

Pavement Performance of Asphalt Mixtures with Economical Low Content Crumb Rubber Modified Asphalt

为了评价低胶粉掺量橡胶沥青对连续密级配混合料性能的影响,采用储存稳定性试验、车辙试验、低温弯曲试验、水稳定性试验和疲劳试验,分别对采用基质沥青、外掺7%和18%胶粉的橡胶沥青混合料工程特性进行了评价。结果表明:外掺7%胶粉制成的橡胶沥青混合料相比于18%胶粉掺量橡胶沥青混合料高温性能、低温性能和疲劳性能均有一定程度衰减,但比普通沥青混合料仍有明显提高;低胶粉掺量沥青混合料试件浸水残留稳定度高于普通沥青混合料和常规胶粉掺量沥青混合料,而冻融劈裂比略低于普通沥青混合料,但高于常规胶粉掺量沥青混合料试样;同时,低胶粉掺量橡胶沥青储存稳定性优于常规胶粉掺量橡胶沥青,且沥青用量降低,具有良好的技术经济性。

In order to evaluate the effect of low content crumb rubber modified asphalt on the pavement performance of continuous graded asphalt mixtures,the storage stability test,wheel track test,low temperature bending test,moisture susceptibility test and fatigue test were carried out to compare the engineering properties of asphalt and mixtures prepared with base binder,7%(by mass of asphalt)and 18%((by mass of asphalt)crumb rubber modified asphalt.The results show that the high temperature stability,low temperature performance and fatigue life of asphalt mixtures modified with 7%crumb rubber are reduced to a certain extent compared with those of mixtures produced with 18%crumb rubber modified asphalt,but they are still significantly improved compared with ordinary asphalt mixtures.In addition,the immersion residual stability of specimens made with low content crumb rubber modified asphalt is higher than that of ordinary asphalt mixture and conventional rubber powder content asphalt mixture,while freeze-thaw splitting ratio is slightly lower than that of ordinary asphalt mixture,but higher than that of conventional rubber powder content asphalt mixture.Meanwhile,the storage stability of rubber asphalt with low rubber powder content is better than that of rubber asphalt with conventional rubber powder content,and when the asphalt content decreases,it has good technical economy.