在役泡沫沥青冷再生混合料性能变化规律

Study on the Property Variation Law of the Cold Recycled Mixture of In-service Foam Asphalt

结合贵阳市新东路改扩建工程项目试验段,基于硬路肩、行车道、超车道处钻芯取样试验,测试服役9年期间泡沫沥青冷再生结构层劈裂强度、动态回弹模量和抗剪切强度,分析在役泡沫沥青冷再生混合料的力学性能、抗剪切性能及泡沫沥青冷再生混合料内泡沫沥青分布状况的变化规律。结果表明:随着服役年限增加,泡沫沥青冷再生路面结构层芯样的劈裂强度、动态回弹模量及黏聚力均不减反增;服役期间泡沫沥青冷再生混合料强度的增长,与新旧沥青浸润融合后旧沥青重新发挥出黏结强度及泡沫沥青冷再生内部新旧沥青重分布等因素相关。

The splitting strength,dynamic resilience modulus and shear strength of cold recycled foam asphalt structural layer during its service period of 9 years were tested based on core sampling tests at hard shoulder,carriageway and overtaking lane combined with the test section of the Xindong Road reconstruction and expansion project in Guiyang City.The mechanical properties,shear resistance and distribution of the cold recycled mixture of in-service foam asphalt were analyzed.The results show that with the increase of service life,the splitting strength,dynamic resilience modulus and cohesiveness of the core of the cold recycled foam asphalt pavement structure are not decreased but increased.The increase of the strength of cold recycled mixture of foam asphalt during service is related to factors such as the bond strength of old and new asphalt after infiltration and fusion and the redistribution of old and new asphalt in cold recycled foam asphalt.