摘要
目的研究橡胶混凝土在盐冻环境作用下的抗冻耐久性并分析冻融后橡胶混凝土的抗弯强度变化,为完善橡胶混凝土抗冻耐久性.方法采取三种不同粒径、三种不同掺量的橡胶粉等体积取代细骨料砂制作橡胶混凝土试件,对其进行质量分数为5%Na 2SO 4溶液侵蚀下的冻融循环试验.结果试验结果表明,随着橡胶掺量的不断增加,橡胶混凝土的相对动弹性模量、抗冻性和抗弯强度都会不断下降.掺量10%、粒径0.18 mm的橡胶混凝土相对动弹性模量降低最少,100次冻融循环后降至96.1%,且高于基准混凝土的92.8%.掺量30%、粒径0.38 mm的橡胶混凝土相对动弹性模量降低最多,降至85%.在抗弯方面,100次冻融循环后基准混凝土的抗弯强度最高,为3.77 MPa,降幅5.51%.橡胶混凝土中,掺量10%、粒径0.25 mm的混凝土强度最高,强度为3.55 MPa,降幅10.17%.结论掺入橡胶粉能改善混凝土的抗冻性,但是会降低混凝土的抗弯强度,橡胶混凝土的抗硫酸盐冻融性能和抗弯强度的最佳取代率为10%.
In order to improve the frost-resistant durability of rubber concrete,the frost resistance durability and flexural strength of rubber concrete under salt-frozen environment are studied in this paper.Rubber concrete specimens,made by mixing rubber with three types of grain size and three contents to replace the fine aggregate in the Portland cement concrete,were used for freeze-thaw cycle test under the erosion of 5%Na 2SO 4 solution.The test results show that the relative dynamic elasticity modulus,frost-resistance and flexural strength decrease with the increasing rubber content.The relative dynamic elastic modulus of rubber concrete was reduced the least by the rubber concrete with 10%,0.18 mm,and it was decreased to 96.1%after 100 freeze-thaw cycles,which was higher than 92.8%of the reference concrete.The relative dynamic elastic modulus of rubber concrete decreases with the addition of 30%,0.38 mm,and it fell to 85%.In bending aspect,after 100 freeze-thaw cycles,the flexural strength of the reference concrete is the highest,3.77 MPa,a decrease of 5.51%.The strength of rubber concrete with 10%,0.25 mm is the highest,and the strength is 3.55 MPa,a drop of 10.17%.The addition of rubber powder can improve the frost resistance of this concrete,however,the flexural strength of concrete will be reduced.The optimum substitution ratio of rubber concrete for the resistance to sulfate solution freeze-thawing and the flexural strength after the freeze-thaw cycle circulations is 10%.
作者
闻洋
崔浩
薛刚
WEN Yang;CUI Hao;XUE Gang(School of Civil Engineering,Inner Mongolia University of Science and Technology,Baotou,China,014010;Beijing Werkhart International Design and Engineering Consulting Ltd,Beijing,China,100097)
出处
《沈阳建筑大学学报（自然科学版）》
CAS
CSCD
北大核心
2020年第2期247-254,共8页
Journal of Shenyang Jianzhu University：Natural Science
基金
国家自然科学基金项目(51768056,51868063)
内蒙古自治区自然科学基金项目(2019MS05038)。
关键词
橡胶混凝土
冻融循环
耐久性
抗弯强度
rubber concrete
freeze-thaw cycles
durability
flexure strength
作者简介
闻洋(1976-),男,教授,博士,主要从事组合结构和混凝土材料方面研究。
