长效自减排改性沥青材料制备及其功效评价

Preparation and Efficacy Evaluation of Long-lasting Self-emission-reduction-modified Asphalt Materials

为减少沥青路面建设-运营-养护期沥青有害物排放,实现道路沥青全寿命周期自减排,提出了减排剂定向合成目标,设计并研制了兼具“微孔-介孔-大孔”多级孔径结构及自发极化效应的新型沥青减排剂,制备了长效自减排改性沥青材料,明确了其路用性能;提出了“建设-运营-养护”全寿命周期自减排改性沥青材料减排功效测试评价方法,深入研究了自减排沥青材料全寿命周期减排功效演变规律,揭示了自减排改性沥青减排功效协同增强作用机理。结果表明:与普通沥青胶浆相比,自减排改性沥青材料高、低温流变及疲劳性能均有不同程度的提升;全寿命周期内,自减排改性沥青材料实现了对CO_(2)、CO、SO_(2)、NOx、H_(2)S、TVOC、PM2.5及PM10等各项有害物主要成分的高效均衡减排,其减排功效随减排剂掺量增加而增强。针对各项有害物主要成分,自减排改性沥青的建设期减排率均超过54%(TVOC减排率最高,达70%);运营期减排率均超过48%(TVOC减排率最高,达64%);养护期,老化后自减排改性沥青减排率变异系数均小于5%。自减排改性沥青混合料/混凝土的建设期减排率均超过54%(PM10减排率最高,达75%),运营期减排率均超过48%(NOx减排率最高,达62%)。自减排改性沥青及其混合料/混凝土的全寿命周期减排功效长效持久。减排剂借助多孔结构及静电场作用吸附了沥青有害物,而后依靠晶体内部电荷迁移原理还原降解了孔内有害物,物理吸附及电荷迁移作用协同增强了自减排改性沥青减排功效。

The purpose of this study was to reduce the emissions of harmful asphalt substances from asphalt pavements during the construction,operation,and maintenance periods and achieve self-emission reduction throughout the full life cycle of road asphalt.A directional synthesis target for an emission-reduction agent was proposed.A new type of emission-reduction agent with a“micropore-mesopore-macropore”multi-level pore structure and a spontaneous polarization effect was designed and developed.A modified asphalt material with long-lasting self-emission reduction was prepared,and its road performance was evaluated.A test and evaluation method for the emission reduction efficacy of self-emission-reduction-modified asphalt materials during the full life cycle consisting of construction,operation,and maintenance was proposed.The evolution of the emission reduction efficacy of self-emission-reduction-modified asphalt materials over their full life cycle was thoroughly studied.A synergistic enhancement mechanism of the emission reduction efficacy of the self-emission-reduction-modified asphalt was revealed.The results show that compared with common asphalt mortar,self-emission-reduction-modified asphalt materials exhibit varying degrees of improvement in their high-and low-temperature rheological and fatigue properties.Over their full life cycle,self-emission-reduction-modified asphalt materials achieved efficient and balanced emission reductions of various harmful components such as CO_(2),CO,SO_(2),NOx,H_(2)S,TVOC,PM2.5,and PM10.The emission reduction effect increased with an increase in the dosage of the emission-reduction agent.During the construction period,the emission reduction rate of the self-emission-reduction-modified asphalt exceeded 54%for all major pollutant components,and the TVOC emission reduction rate was the highest,reaching 70%.During the operation period,the emission reduction rate exceeded 48%and the TVOC emission reduction rate was the highest,reaching 64%.During the curing period,the variation coefficients of the emission reduction rates of the self-emission-reduction-modified asphalt after aging were<5%.During the construction period,the emission reduction rate of the self-emission-reduction-modified asphalt mixture/concrete exceeded 54%,and the emission reduction rate of PM10 was the highest at 75%.During the operation period,the emission reduction rate exceeded 48%and the NOx emission reduction rate was the highest,reaching 62%.The emission reduction efficacy of self-emission-reduction-modified asphalt and its mixtures/concrete was long term and continuous throughout its entire life cycle.The emission-reduction agent absorbed harmful asphalt substances through its porous structure and electrostatic field action.Harmful substances in the pores were reduced and degraded based on the principle of charge transfer within the crystal.The synergistic effects of physical adsorption and charge transfer enhanced the emission reduction efficacy of the self-emission-reduction-modified asphalt.