Analysis of macro-fine cracking characteristics of Butun rock asphalt concrete under repetitive loading at multiple frequencies
To address the problem related to the service life of Butun rock asphalt concrete pavement under different operating condi-tions,the fatigue damages of Butun rock asphalt concrete,matrix asphalt concrete,and SBS modified asphalt concrete were ana-lyzed under five types of road environments and different frequencies of repetitive loads by three-point bending repetitive loading tests of Butun rock asphalt concrete beam specimens combined with digital image correlation(DIC)technique.The fatigue damage of Butun rock asphalt concrete,matrix asphalt concrete and SBS modified asphalt concrete in five road environments were analyzed by DIC technique.The results show that the fatigue life under different road environments and multi-frequency is in the order of SBS-modified asphalt concrete>Butun rock asphalt concrete>base asphalt concrete.The fatigue performance of asphalt concrete is improved by the addition of Butun rock,but the sensitivity to the change of vehicle speed is strong.The fatigue cracking resistance of asphalt concrete is enhanced by the addition of Butun rock.The degree of damage same material under the same number of repetitive loading action decreases with the increase in loading frequency.Butun rock admixture can improve the mixture's resistance to dam-age and delay the asphalt concrete appeared accelerated cracking time point.Macroscopic cracks appeares when the repetitive loads accounted for 70%of the role of the number of times for Butun rock asphalt concrete.The findings herein can be conducive to the developments of appropriate prevention and control measures in advance in practical projects.
NETL
NSTL
万方数据
