摘要
针对公路预应力桥梁在预制构件施工过程中周期长、成本高的问题,为了满足快速高质量施工的要求,系统研究了不同原材料种类和掺量、砂率、水胶比等因素对混凝土的工作性能及力学性能的影响规律,通过掺入早强超分散减缩外加剂调控混凝土性能,确定了预应力T梁C70混凝土采用低掺量粉煤灰和矿粉复掺,总胶凝材料控制在540kg/m^(3),砂率0.38,水胶比0.24。为缩短施工周期可采用蒸养促进早期强度提高减少服役期间收缩,探究了非蒸汽养护和蒸汽养护时,C70混凝土体积稳定性,通过SEM等测试手段分析混凝土早强与收缩时微结构演变。
In order to meet the requirement of rapid and high quality construction,highway prestressed bridge is faced with the problem of long period and high cost in the construction process of prefabricated components.The effects of different raw material types,mixing amount,sand ratio and water-cement ratio on the working performance and mechanical properties of concrete were systematically studied.It is determined that the prestressed T-beam C70 concrete is mixed with low fly ash and mineral powder,and the total cementitious material is controlled at 540 kg/m^(3),the sand ratio is 0.38,and the water-cement ratio is 0.24.In order to shorten the construction period,steam curing can be adopted to promote early strength improvement and reduce shrinkage during service.The volume stability of C70 concrete during non-steam curing and steam curing is explored,and the microstructure evolution of concrete of early strength and shrinkage was analyzed by SEM.
作者
黄祥
李宏斌
丁庆军
HUANG Xiang;LI Hong-bin;DING Qin-jun(Guangdong Changda Experimental Technology Development Limited Company,Guangzhou 511430,China;State Key Laboratory of Silicate Materials for Architectures,Wuhan University of Technology,Wuhan 430070,China)
出处
《武汉理工大学学报》
CAS
北大核心
2019年第7期55-62,共8页
Journal of Wuhan University of Technology
关键词
先张法
T梁
早强
体积稳定性
pretensioning method
T-beam
early strength
volume stability
