摘要
利用改性玄武岩粉(MBP)、复合矿渣粉(CSP)、普通硅酸盐水泥(C)、石膏(G)等为原材料,设计一种适用于路面基层的复合胶凝材料,通过调整胶凝材料各组分相对比例,保证不同龄期强度满足工程需求。结果表明:CSP和MBP的加入可有效延长路面基层胶凝材料的初凝和终凝时间,初凝时间大于4 h,终凝时间6~10 h;路面基层胶凝材料90 d力学强度随MBP掺量的增加而提高;随组分中SO_(3)含量的增加,路面基层胶凝材料的干燥收缩速率和总收缩值呈降低的趋势;胶凝材料中硫酸盐含量的增加有利于水化产物的生长,可以提高试件的强度;SO_(3)与铝酸盐矿物发生水化生成钙矾石,具有一定的膨胀性,可以补偿干燥收缩,降低材料早期干燥收缩速率和总收缩值,进而降低路面基层发生干缩开裂的可能。
The short setting time and high early strength of ordinary Portland cement make it difficult to match the usage requirements of highway pavement base materials.The composite cementitious material suitable for pavement base is designed using modified basalt powder(MBP),composite slag powder(CSP),ordinary Portland cement(C),gypsum(G)as raw materials,and the relative proportions of each component in the cementitious material are adjusted to meet the engineering requirements of the strength at different ages.The results shows that,the initial and final setting time of pavement base cementitious materials are effectively prolonged with the addition of CSP and MBP,with an initial setting time greater than 4 hours and a final setting time of 6 to lo hours.The mechanical strength of pavement base cementitious material for 90 d increases with the increase of MBP content.With the increase of SO_(3)content in the hydration products,the dry shrinkage rate and total shrinkage value of the pavement base cementitious material present a decreasing trend.The increase in sulfate content facilitates the growth of hydration products and improves the strength of the specimen.SO_(3)hydrates with aluminate minerals to produce ettringite,which has certain expansibility,can compensate for drying shrinkage,reduce the early drying shrinkage rate and total shrinkage value of the material,and thus reduce the possibility of dry shrinkage cracking in the pavement base.
作者
杜留现
王光明
郭炎飞
郅真真
DU Liu-xian;WANG Guang-ming;GUO Yan-fei;ZHI Zhen-zhen(Ruyang Transportation Development Center,Luoyang 471200,China;School of Materials Science and Engineering,Luoyang Institute of Science and Technology,Luoyang 471023,China)
出处
《公路》
北大核心
2025年第8期309-315,共7页
Highway
基金
国家自然科学基金项目,项目编号52102024
河南省本科高校青年骨干教师培养计划项目,项目编号2023GGJS163。
关键词
路面基层
复合胶凝材料
总收缩值
干燥收缩速率
pavement base course
composite cementitious material
total shrinkage value
drying shrinkage rate
