多孔沥青混合料的疲劳特性试验研究

采用应力控制模式对不同材料组成的多孔沥青混合料进行疲劳试验,分析了空隙率、油石比和浸水状态对混合料疲劳特性的影响,并比较了不同油石比的沥青混合料在不同浸水时间下的疲劳特性差异.结果表明:多孔沥青混合料的抗疲劳性能随空隙率的增大而减小;随着油石比的增大,多孔沥青混合料疲劳寿命的应力敏感性降低,存在着最佳油石比,在最佳油石比下混合料的抗疲劳性能最好;浸水状态对多孔沥青混合料的疲劳特性影响与油石比大小密切相关,当油石比适中或偏大时,浸水3～10 d对其疲劳特性影响较小.

Study on the Fatigue Characteristic of Porous Asphalt Concrete

Porous asphalt concrete with different material composition were studied by the fatigue test of stress control model, effect of air voids, asphalt aggregate ratio and saturation condition on the fatigue characteristic were investigated. The fatigue characteristics of porous asphalt concrete with different asphalt aggregate ratio and saturation time were compared by saturation fatigue tests. The results of the study show that the anti fatigue performance of porous asphalt concrete is decreased with the increase of the air voids; and the stress sensitivity of porous asphalt concrete was decreased as the value of asphalt aggregate ratio increased. There exist an optimum asphalt aggregate ratio which provides a best fatigue characteristic. Effects of saturation condition on the fatigue characteristic of porous asphalt concrete were closely related to the value of asphalt aggregate ratio, there will be only little influence when the value of asphalt aggregate ratio is moderate or larger.