基于水基发泡的温拌沥青混合料压实性能试验研究

Research on Compaction Performance of Warm Mix Asphalt Mixture Based on Water-based Foaming

为探究泡沫温拌沥青混合料的压实特性,基于灰色关联理论分析了沥青温度和发泡用水量对沥青发泡效果的影响。并基于最佳发泡条件,通过室内试验研究了压实温度对泡沫沥青混合料力学性能的影响;采用变击实功马歇尔击实试验探究了压实参数随击实次数的变化规律。研究结果表明,发泡用水量对沥青发泡效果影响较大,当用水量为3.6%时,混合料内部残留水最少,压实效果最好;与普通热拌沥青混合料相比,泡沫温拌沥青混合料的压实温度可降低30℃,减少了约14.3%的CO2和5.6%的苯可溶物排放;随着击实次数的不断增加,压实度和稳定度分别呈幂函数与线性增长,当连续击实次数>100次时,试件变得较难以击实;基于压实系数模型计算得到,泡沫沥青混合料达到最佳密实度所需的最小击实次数为155次。

To explore the compaction properties of foamed Warm-Mix Asphalt(WMA),the influences of foaming temperature and water content on bitumen foaming effect have been investigated based on the grey correlation method,and as per the optimal foaming conditions,the compaction temperature is studied through laboratory tests.The variable compaction power Marshall compaction test is used to explore the changing law of compaction parameters with compaction times.The research results show that the foaming water content has a great influence on the foaming effect of asphalt.When the water consumption is 3.6%,the residual water in the mixture is the least and the compaction effect is the best.Compared with ordinary HMA,the compaction temperature of the foamed warm-mix asphalt mixture can be reduced by 30℃,which reduces the emission by about 14.3%of CO2and 5.6%of benzene solubles.With the continuous increase of the number of compaction,the compactness and the stability increase in the form of power function and linear respectively.When the number of continuous compaction N>100times,the specimen becomes more difficult to be compacted.Based on the definition model of compaction coefficientν,it is calculated that the minimum number of compaction required for the foamed asphalt mixture to achieve the best compactness is 155.