摘要
由于集料与水泥石变形的不一致,导致混凝土内部结构缺陷几率增大。因此,强度超过150MPa的超高强水泥基材料,如无宏观缺陷水泥基材料(MDF)、活性粉末混凝土(RPC)及工程粘性材料(ECC)等制备时必须剔除粗集料。本文在不剔除粗集料的情况下,采用普通工艺和常规材料,制得了365天龄期时抗压强度为178.3MPa,坍落度210mm的超高强高性能混凝土,同龄期、同配比下的砂浆强度达到178.2MPa,净浆强度达到179.5MPa,混凝土、砂浆及水泥石强度均超过所用粗集料的母岩强度。以此为基础,分析了混凝土各组成结构的微观结构及微观力学特征,探讨了不剔除粗集料的情况下,制备超高强混凝土的理论基础。
Coarse aggregate is removed as a common practice when super high strength cement-based materials of 150MPa or over, such as RPC, MDF, and ECC, are prepared, this is because the deformation of harden paste is different from that of coarse aggregate, which gives rise to defect increasing of the concrete product. Without removing coarse aggregate, this paper focused on the preparation of super high strength concrete, which had compressive strength of 178. 3MPa at 365 days and slump of 210 mm when common technology and ordinary materials were used. It is discovered that the strength of concrete, mortar and harden paste were higher than strength of coarse aggregate. The micro-structure and micro-mechanics of harden paste, interracial transition zone (ITZ) and aggregate of concrete are discussed, and the fundamental of mechanical properties of super high strength concrete is analyzed.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2008年第4期516-519,共4页
Journal of Materials Science and Engineering
基金
国家自然科学基金"高强与高性能混凝土的结构与力学性态研究"重点资助项目(59338120)
关键词
超高强混凝土
强度机理
制备
粗集料
super high strength concrete
fundamental of mechanical properties
preparation
coarse aggregate