摘要
钢渣粗集料体积安定性不良且变异性大,容易造成钢渣沥青混凝土在长期服役过程中出现体积膨胀和耐久性风险。为此,通过压蒸试验分析钢渣粗集料的体积安定性,利用钢渣-辉绿岩粗集料单掺或混掺方式进行5种沥青混凝土配合比设计。以辉绿岩沥青混凝土和压蒸后稳定的钢渣粗集料制备的沥青混凝土作为基准,开展60℃不同浸水时间下钢渣沥青混凝土体积膨胀特性、间接拉伸强度和耐疲劳性能衰减规律研究,通过不同钢渣掺量与浸水时间建立了钢渣沥青混凝土长期浸水体积膨胀率预估模型,利用浸水时间和钢渣掺量提出了残留强度与残留疲劳寿命预估模型以分析力学性能衰减规律。结果表明:压蒸试验可快速检验钢渣粗集料不良体积安定性;钢渣沥青混凝土长期浸水后的间接拉伸强度、模量及疲劳寿命均呈明显衰减趋势;钢渣沥青混凝土的间接拉伸强度与疲劳试验结果具有良好的线性相关性,利用间接拉伸强度残留率可实现钢渣沥青混凝土使用耐久性的快速评价;钢渣沥青混凝土体积膨胀与强度损失、模量损失及疲劳寿命损失呈指数下降关系;不良钢渣颗粒体积膨胀破坏对钢渣沥青混凝土力学性能劣化具有决定性作用,应在钢渣源头与选材上控制钢渣稳定性。
The steel slag coarse aggregate has poor volumetric stability with large variability,which could result in volume expansion and durability risk for steel slag asphalt concrete during long-term service period.For this purpose,the volumetric stability of steel slag coarse aggregate was tested by using autoclave test.Five different types of asphalt concrete were designed by using the single or hybrid addition of steel slag and diabase coarse aggregate.The asphalt concrete,prepared with diabase asphalt concrete and stabilized steel slag coarse aggregate after autoclaving,was used as the reference.This study investigated the volume expansion characteristics,indirect tensile strength,and fatigue resistance attenuation rule of steel slag asphalt concrete at 60℃with different immersion periods.The prediction model of volume expansion rate for steel slag asphalt concrete was established based on the different steel slag contents and water immersion periods.The prediction models of residue strength and fatigue life were proposed due to the water immersion and steel slag content to analyze the mechanical property attenuation rule.The result indicates that the autoclave test can quickly examine the poor volumetric stability of steel slag coarse aggregate.After long-term water immersion,the indirect tensile strength,modulus and fatigue life of steel slag asphalt concrete show the obvious attenuation trend.The results obtained from indirect tensile strength and fatigue tests on steel slag asphalt concrete show the good linear correlation.By using the indirect tensile strength residual rate can quickly evaluate the service durability of steel slag asphalt concrete.The steel slag asphalt concrete volume expansion shows the exponential decay relations with strength loss,modulus loss,and fatigue life loss.The volume expansion destruction of poor quality steel slag particles has a decisive effect on the deterioration of mechanical properties of steel slag asphalt concrete.The steel slag stability should be controlled at the source and in material selection.
作者
李想
王利波
吕维前
磨炼同
肖月
LI Xiang;WANG Li-bo;L Wei-qian;MO Lian-tong;XIAO Yue(State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan,Hubei 430070,China;Henan Anyang-Luoshan Expressway Co.,Ltd.,Zhengzhou,Henan 475002,China;School of Material Science and Engineering,Chang’an University,Xi’an,Shaanxi 710061,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2024年第11期2-13,共12页
Journal of Highway and Transportation Research and Development
基金
山西省交通运输厅科技项目(2021-1-7)
中交二公局科技项目(G19SLLX030-QT083)
山西路桥建设集团科研项目(D03(201911)01)。
关键词
道路工程
力学衰减机理
长期浸水
钢渣粗集料
混凝土
耐久性
road engineering
mechanical attenuation mechanism
long-term water immersion
steel slag coarse aggregate
concrete
durability
作者简介
李想(2000-),男,黑龙江黑河人,硕士研究生,330994@whut.edu.cn;通讯作者:磨炼同(1979-),男,广西南宁人,博士,副研究员,molt@whut.edu.cn。
