盐溶液与高温耦合作用下沥青混合料性能衰变规律及防治措施

Decay Regularity and Improvement Measures of Road Performance and Mechanical Properties of Asphalt Concrete under Salt-Wet-Heat Condition

为准确评价盐-湿-热循环作用对沿海含盐高湿区沥青混合料路用性能和疲劳性能的损伤规律,针对沿海高温多雨地区沥青路面在荷载、高温、海盐水冻融循环作用下剩余弯拉强度和疲劳寿命进行研究,制定了适宜的盐-湿-热循环试验方案,分析给出了盐-湿-热循环作用下沥青混合料路用性能、疲劳性能的损失率计算模型。进而对比分析了硅藻土、岩沥青、木质素纤维、聚酯纤维、玄武岩纤维、抗剥落剂ARM、消石灰对含盐高湿环境沥青混凝土路用性能和疲劳性能的改善效果。试验结果表明:在盐-湿-热循环过程中沥青混合料的车辙试验动稳定度、弯曲应变、弯拉强度、疲劳寿命能衰变规律符合logistics生长曲线模型。沥青混合料各项路用性能、力学性能、抗疲劳性能劣化程度随着盐溶液浓度增大而增大,当盐溶液溶度超过10%后,继续增大盐溶液浓度沥青混合料性能劣化速率减小;前20次盐-湿-热循环作用下沥青混合料路用性能衰变劣化程度较为明显,继续增大盐-湿-热循环次数后沥青混合料高低温和水稳定性能劣化速率减小,可采用10%盐溶液浓度和盐-湿-热循环20次来模拟盐-湿-热侵蚀环境对沥青路面的负面影响;纤维类添加剂对含盐高湿环境沥青混合料抗疲劳性能、低温性能及高温性能改善效果最优,硅藻土对沥青混合料水稳定性改善效果最好,抗剥落剂和消石灰对沥青混合料在盐-湿-热循环作用后路用性能改善效果最差,建议在沿海含盐高湿地区优先采用玄武岩纤维来提高沥青混合料的水稳定性和抗疲劳耐久性能。

In order to accurately evaluate the damage law of salt- weet-ance and fatigue performance of asphalt mixture in coastal salt and high-humidity high temperature and sea salt water freezing-thawing cycle Wet-heat cycle , and the loss-rate calculationmodel of asphalt mixture under salt- wet-heat cycle is given and analyzed. The resultscan be used to calculate the fatigue life of the asphalt mixture. The effects of diatomite , rock asphalt , lig-nin fiber , polyester fiber , basalt fiber , anti-stripping agent ARM and slaked lime on road performance and fatigue properties of asphalt concrete with salt and high humidity were compaexperimental results show that the dynamic stability , flexural strain , flexural strength and fatigue life de-cay of asphalt mixture in the salt - wet - heat cycle process are in accordance with the logistics growthcurve model. ; asphalt mixture road performance, mechanical properties, fatigue performance degradation with the salt solution concentration increases, when the salt solution of more than 1 0 %, continue to in-crease the concentration of salt solution asphalt mixture performance degradation Andof road asphalt mixture under the first 20 salt-＇ wet-heat cycles is more obvious, and tion of the asphalt mixture is decreased after increasing the number of saused to simulate the negative effect of salt- wet-thermal erosion environment on asphalt pavement by using10% salt solution concentration and salt-＇ wet-heat cycle 20 times. The effect of fiber additives on anti- fa-tigue properties of asphalt mixture containing salt and high humidity Diatomite has the best effect on im-proving the water stability of asphalt mixture. The anti-stripping agent and slaked lime have the poorestimprovement effect on the asphalt mixture after salt-＇ wet-heat cycle, It is suggbe given priority to improve the water stability and fatigue resistance of the asphalt line and wet areas.