摘要
针对冲击荷载作用下橡胶混凝土的损伤问题,利用自动冲击球压仪对橡胶混凝土的动态冲击损伤行为进行研究,并应用激光共聚焦扫描显微镜(LSCM)和扫描电子显微镜(SEM)分析了其冲击损伤形貌及机理特征。结果表明:冲击荷载下橡胶混凝土抗冲击能力优于基准混凝土,且随橡胶粒径的减小抗冲击能力增强;随着冲击荷载的不断增加,橡胶混凝土的压痕增长速率小于基准混凝土,极限荷载值却大于基准混凝土,而橡胶粒径的减小,使压痕增长速率呈减小趋势,极限荷载值增大,表面抗塑性变形能力及试样表面动态力学性能增强;冲击荷载下材料表面形成球冠状小坑,压痕边缘出现不同程度的材料堆积,80目的橡胶在混凝土中分布更加均匀,且损伤区较为连续无明显微裂纹。研究结果为冲击荷载作用下对橡胶混凝土材料损伤研究提供依据。
Aiming at damage problems of rubber concrete under impact loads,an automatic impact ball pressure instrument was used to study dynamic impact damage behavior of rubber concrete.Morphology and mechanism features of impact damage were analyzed with a laser scanning confocal microscopy(LSCM)and a scanning electron microscope(SEM).Results showed that impact resistance ability of rubber concrete under impact loads is stronger than that of normal concrete,and its impact resistance ability is enhanced with decrease in rubber particle diameter;with continuous increase in impact loads,indentation growth rate of rubber concrete is smaller than that of normal concrete,while its ultimate load value is larger than that of normal concrete;with decrease in rubber particle diameter,its indentation growth rate tends to decrease,while its ultimate load value increases,and its anti-plastic deformation ability and its specimen surface’s dynamic performance are enhanced;under impact loads,coronal pits are formed on its surface,different degrees of material accumulation appear at indentation edges,80-mesh rubber is distributed more uniformly in concrete,and damage zones are more continuous and there are no obvious micro-cracks;the results provide a basis for studying damage of rubber concrete under impact loads.
作者
郝贠洪
樊磊
韩燕
李慧
田旭乐
郝庆丽
HAO Yunhong;FAN Lei;HAN Yan;LI Hui;TIAN Xule;HAO Qingli(School of Civil Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Inner Mongolia Key Lab of Civil Engineering Structure and Mechanics,Inner Mongolia University of Technology,Hohhot 010051,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2019年第17期73-80,共8页
Journal of Vibration and Shock
基金
国家自然科学基金(11162011
11662012
51468049)
内蒙古自治区人才开发基金项目
关键词
冲击荷载
损伤机理
冲击球压
橡胶混凝土
压痕形貌
impact load
damage mechanism
impact ball pressure
rubber concrete
indentation morphology
