复杂状态下桥用高强混凝土收缩徐变性能试验  

Creep and shrinkage of high strength concrete for bridges under complex condition

作　　者：赵启林[1] 陈立[1] 翟可为[1] 杨洪[1] 宋建国[1] 

机构地区：[1]解放军理工大学工程兵工程学院,江苏南京210007

出　　处：《解放军理工大学学报（自然科学版）》2011年第5期459-465,共7页Journal of PLA University of Science and Technology(Natural Science Edition)

基　　金：国家863计划资助项目(2007AA11Z120)

摘　　要：针对大量大跨度预应力混凝土桥梁长期变形难以准确预测的现状,分析了多种高强混凝土收缩徐变预测模型分别在实验室和实际桥梁工程条件下的适用性,指出了现有预测模型并没有考虑大跨度预应力桥梁桥用混凝土早期受循环荷载作用等特点。制作了7组不同应力比、不同荷载循环周期的试件,对混凝土的收缩徐变性能进行了测试与分析。研究结果表明,高强混凝土早期遭受的循环荷载作用将明显加大混凝土徐变,而且徐变值受到应力比、循环周期等影响。Given that the long-time distortion of most big span prestressed concrete bridges could not be predicted accurately,the applicability of several creep prediction models of high strength concrete in the respective conditions of laboratory and real bridge engineering was studied,and the specialties of the existing prediction models such as excluding the effect of repeated load affected on the concrete at early age for big span prestressed concrete bridges were illuminated.Then 7 groups of concrete specimens for different stress ratios and different loading periods were made,and their creep performances tested and analyzed.The research shows that the repeated load affected on high strength concrete at early age will aggravate its creep remarkably,and the creep value is influenced by stress ratio,loading periods,and etc.

关 键 词：桥梁 收缩徐变 高强混凝土 循环荷载 

分 类 号：U448.35[建筑科学—桥梁与隧道工程]