粗骨料品种对C55耐久混凝土性能的影响  

Effect of Coarse Aggregate on Durability of C55 Concrete

作　　者：苏祖平[1,2] 叶小吁[1,2] 陈露一[1,2] 欧阳华林[1,2] 

机构地区：[1]中铁大桥局集团桥科院有限公司,湖北武汉430034 [2]桥梁结构安全与健康湖北省重点实验室,湖北武汉430034

出　　处：《世界桥梁》2014年第4期79-82,共4页World Bridges

摘　　要：黄韩侯铁路上的桥梁设计为后张法预应力混凝土T形简支梁,主梁在制梁场预制,要求混凝土强度等级为C55,56d混凝土的电通量≤1 000C。考虑碎石的技术指标、运距和成本因素,选取了黑云母花岗闪长岩碎石和结晶灰岩碎石2种粗骨料。为优选出满足要求的碎石,配制满足工程要求的混凝土,采用这2种粗骨料配制C55混凝土,对混凝土的拌合物工作性、力学性能及抗氯离子渗透性能等进行试验,并采用光学显微镜对2种粗骨料的微观结构进行了分析。结果表明:使用黑云母花岗闪长岩碎石配制的C55耐久混凝土的弹性模量及电通量不能满足铁路规范要求,而使用结晶灰岩碎石配制的C55耐久混凝土的弹性模量及电通量均能满足铁路规范要求。The bridge on the Huangling-Hancheng-Houma Railway is a post-tensioned pres-tressed concrete simply supported T-shaped girder bridge .The main girder was prefabricated in the workshop ,the strength of concrete was required being C55 and the electric flux of the concrete aging 56 d being no less than 1 000 C .Given the technical indexes ,transportation distance and cost of the crushed stones ,the biotite granodiorite gravels and crystalline limestone gravels were con-sidered .In order to select out the type of gravels that can meet the requirements so as to prepare the concrete which suits the project demands ,the two kinds of aggregates aforementioned were used to prepare C55 concrete ,with the intention of testing the properties of the mixing materials , mechanical behavior and resistance to chloride ion penetration of the concrete .In addition the opti-cal microscope was used to analyze the microstructure of the two kinds of aggregates ,The results indicate that the elastic modulus and electric flux of the C55 concrete with biotite granodiorite gravels can not meet the railway code requirements ,but those of the C55 concrete with crystalline limestone gravels can meet the railway code requirements .

关 键 词：混凝土 粗骨料 配合比 耐久性 工作性 强度 弹性模量 电通量 试验 

分 类 号：TU528[建筑科学—建筑技术科学]