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本学术报告概括地描述了(美)国内外膨胀水泥混凝土发展的历史,解释有关的术语,并总结美国膨胀水泥的现状。叙述了膨胀水泥的水化反应,并着重指出了形成 E 盐所必需的成分,讨论了选取材料配比的几个重要因素以及反应生成物和水化热。对那些会影响三种类型的膨胀水泥混凝土的膨胀率和膨胀的的各种因素都加以研究,这些因素包括:化学成份、水泥细度和存放时间、水灰比、拌和时间、各种掺料、骨料、养护、温度、约束条件和试件的尺寸及形状等。关于膨胀水泥混凝土的性质是按收缩补偿混凝土和自应力混凝土分开介绍的(收缩补偿混凝土国内亦译称不收缩混凝土或膨胀混凝土——译注),所考虑的性质包括:和易性、析水、凝结时间、单位重和单产量(意即每方混凝土中的水泥用量——译注)、膨胀、蠕变、收缩、抗压强度和粘结强度、弹性模数、泊桑比、热膨胀系数和各种抵抗作用(抗冰冻剥落、抗酸蚀、抗裂和抗磨蚀),还指出了那些现在尚缺乏可靠数据的性质。扼要说明了收缩补偿混凝土的现场施工,对于约束条件、骨料、补加剂、四周温度、模板、稠度、抹面和养护等方面的影响,均加以论述。列举出结构构件的实例,其中有平板、单向槽形板、停车场车库的双向格子板、银行的折板式屋顶、停车场的单丁形予应力面板结构、百货商店货栈的斜板和复面墙板以及工业厂房地坪等。介绍了五条公路的设施,它包括:各种间距的收缩缝,有连续配筋的路面和无筋的路面、自应力混凝土在公路上的一次应用、和二座桥面的使用情况。总结了在试验室进行的17个自应力混凝土结构构件的试验成果,其中包括:管子、平板、梁、框架、柱和双曲抛物线薄壳,并简单评价某些国外经验。本文讨论了各种膨胀水泥的材料性质、功效和用途等方面所需要研究的范围及发展方向。并列出了大量的参考资料。
This report summarizes the history of (US) domestic and international expansion of cement concrete, explains the relevant terminology, and summarizes the current status of US expanded cements. The hydration reaction of expansive cement was narrated. The necessary components of forming E salt were emphatically pointed out. Several important factors of the selection of materials and the reaction products and hydration heat were discussed. Various factors that affect the rate of expansion and expansion of three types of expanded cement concrete are studied, including: chemical composition, cement fineness and shelf life, water-cement ratio, mixing time, , Aggregate, conservation, temperature, constraints and specimen size and shape. The properties of expanded cement concrete are introduced separately from shrinkage-compensated concrete and self-stressing concrete. The properties considered include: workability, water analysis, Setting time, unit weight and unit yield (ie, the amount of cement in each concrete), expansion, creep, shrinkage, compressive strength and bond strength, modulus of elasticity, Poisson’s ratio, coefficient of thermal expansion The resistance (freeze-resistant, freeze-resistant, acid-resistant, crack-resistant and abrasion-resistant) also points to the lack of reliable data. The construction of shrinkage compensated concrete is briefly described, and the influences on the restraint conditions, aggregates, additives, surrounding temperature, formwork, consistency, plastering and curing are all discussed. Examples of structural components are listed, including flat plates, one-way slotted plates, two-way grate plates for parking garage, bent roofs for banks, monobloc prestressed panel structures for parking lots, swash plate and complex of department store shelves Wall panels and industrial floor and so on. The facilities of five highways are introduced. They include: contraction joints of various spacings, pavement with continuous reinforcement and non-reinforced pavement, application of self-stress concrete on the highway, and the use of two decks. The test results of 17 self-stressing concrete structural members carried out in the laboratory were summarized, including: pipes, slabs, beams, frames, columns and hyperbolic parabolic shells, and a brief evaluation of certain foreign experiences. This article discusses the material properties of the various types of expansion of the cement, efficacy and use of the required areas of research and development direction. And lists a lot of reference material.