摘要
为研究道路混凝土微观结构与其耐磨性之间的相关性,基于道路混凝土路表砂浆层对其耐磨性的影响,提出以砂浆体积分数作为道路混凝土耐磨性设计参数,对不同砂浆体积分数和水灰比条件下的道路混凝土进行抗压强度和耐磨性试验,借助数字图像处理技术、压汞试验和扫描电镜研究了不同设计参数条件下的道路混凝土气孔结构、孔结构及微观形貌的变化规律,并对其微观结构与耐磨性之间的相关性进行了分析。研究结果表明:道路混凝土的抗压强度及耐磨性会随着砂浆体积分数增大而提高,而减小水灰比也可提高混凝土的抗压强度和耐磨性,且砂浆体积分数对耐磨性的影响更为显著;砂浆体积分数从0.52增大至0.58时,道路混凝土抗压强度提高23%,耐磨性增强50%;水灰比从0.46减小至0.40时,道路混凝土抗压强度提高21%,耐磨性增强41%;随着砂浆体积分数增大和水灰比减小,混凝土内部孔结构和气孔结构特征参数均逐渐减小,小于100 nm的孔占比增大,道路混凝土微观结构得到改善,混凝土内部结构趋于密实,有利于增强道路混凝土耐磨性;道路混凝土磨耗量与其气孔结构和孔结构相关性具有一定差异,其中磨耗量与平均气孔孔径相关性最强,与气孔间距系数相关性次之,与总气孔率相关性较弱;而磨耗量与50~100 nm的孔占比相关性最强,与各孔结构特征参数相关性次之,与大于200 nm的孔占比相关性较弱。
In order to study the correlations between the microstructure and abrasion resistance of concrete pavement,the influence of mortar layer on the abrasion resistance of concrete pavement was considered,and the mortar volume component was used as an important design parameter for the abrasion resistance of concrete pavement,the compressive strength test and abrasion resistance test were used for the concrete pavement with different mortar volume components and water-cement ratios,in addition,the digital image processing technology,mercury intrusion porosimetry and scanning electron microscope have been used to study the change laws of the stomatal structure,pore structure and micro topography under different design parameters,and the correlations between microstructure and abrasion resistance of road concrete have been analyzed.The results show that the compressive strength of road concrete improves with the increase of the mortar volume component or the decrease of water-cement ratio,and the abrasion resistance of road concrete improves with the increase of mortar volume component or the reduction of water-cement ratio,and the effect of mortar volume component on abrasion resistance is more significant.When the mortar volume component increases from 0.52 to 0.58,the compressive strength of road concrete improves by 23% and the abrasion resistance increases by 50%.When the water-cement ratio decreases from 0.46 to 0.40,the compressive strength of road concrete improves by 21%and the abrasion resistance increases by 41%.With the increase of the mortar volume component and the decrease of water-cement ratio,the parameters of stomatal structure and pore structure of concrete reduce gradually,and the percentage of<100 nm pores increases,so the microstructure of concrete improves and internal structure of concrete tends to be dense,which is conducive to enhance the abrasion resistance of road concrete.The correlations between abrasion value and stomatal structure is different from that between abrasion value and pore structure.Further,the abrasion resistance has strongest correlations with the average stomatal size,followed by the correlations with the stomatal spacing coefficient,and has weak correlations with the total stomatal rate.However,the abrasion value has the strongest correlations with the percentage of 50 to 100 nm pores,followed by the characteristic parameters of each pore structure,and has weak correlations with the percentage of>200 nm pores.
作者
郭寅川
申爱琴
翟超伟
李鹏
GUO Yin-chuan;SHEN Ai-qin;ZHAI Chao-wei;LI Peng(School of Highway,Chang'an University,Xi'an 710064,Shaanxi,China;Louisiana Transportation Research Center,Louisiana State University,Baton Rouge LA70803,Louisiana,USA;Henan Provincial Communications Planning&Design Institute Co.Ltd,Zhengzhou 451464,Henan,China)
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2019年第6期1-11,共11页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(51608047,51778061)
关键词
道路工程
耐磨性
压汞试验
砂浆体积分数
微观结构
相关性
road engineering
abrasion resistance
mercury intrusion porosimetry
mortar volume component
microstructure
correlation
