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High early strength

Accelerator in Ready-Mix Concrete. Calcium chloride accelerates the set time of concrete giving it a high early strength development. It is not an antifreeze, but by using it duriag cold weather protection can proceed in a timely manner (31—34). In Russia, calcium chloride forms a component of several antifreeze admixtures (33). Reviews of the concerns and possible remedies of calcium chloride corrosion problems in concrete are available (21,35). There is no consensus on what the safe levels of calcium chloride in concrete are. [Pg.416]

Concrete, Mortar, and Plaster. Citric acid and citrate salts are used as admixtures in concrete, mortar, and plaster formulations to retard setting times and reduce the amount of water requited to make a workable mixture (172—180). The citrate ion slows the hydration of Portland cement and acts as a dispersant, reducing the viscosity of the system (181). At levels below 0.1%, citrates accelerate the setting rate while at 0.2—0.4% the set rate is retarded. High early strength and improved frost resistance have been reported when adding citrate to concrete, mortar, and plaster. [Pg.186]

Class C Intended for use from surface to 6,000 ft (1,830 m) depth, when conditions require high early strength. Available in ordinary and moderate (similar to ASTM C 150, Type III) and high-sulfate-resistant types. [Pg.1182]

High deviation alarm, 20 672 High dust plant, 10 101 High early strength cements, 5 498t, 500-501... [Pg.434]

High early strengths at reduced costs (use of lower cement contents, alternative cement) are attained so that forms are stripped earlier and rapid delivery time is ensured. [Pg.507]

Type III High-early-strength (HES) cements are made from raw materials with a lime-to-silica ratio higher than that of Type I cement and are ground finer than Type I cements. They contain a higher proportion of calcium silicate than regular portland cements. [Pg.156]

Anchoring systems are materials used mainly for securing bolts, bars, tendons or dowels in drilled or formed holes in concrete, masonry or natural rock. Polyester anchors are widely used because of their fast curing property and high early strength (Fosroc International, undated a). Epoxy anchors are applied in areas where there is a risk of alkaline hydrolysis. [Pg.18]

High-early-strength portland cement as specified in JIS R 5210 (Portland Cement) was used in all the mortar mixes for artificial woods. [Pg.128]

Two types of pulp sand mortar were used as the core plate of sandwich specimens. Mortar of Type M was made by mixing high-early-strength Portland cement, silica fume and pulp sand. Mortar of Type P was made directly with pulp sand. Mix proportions of each type of mortar are shown in Table 1 and Table 2. Pressurized forming was used to produce mortar plates of each type, whose pressure was lOMPa. Then specimens were put in a moist room of 20 C for about one day. After steam curing at 50 C for 24 hours, they were autoclave-cured on condition of 180 C for 3 hours. Finally they were dried out in an electric oven of 110 C for 24 hours. The geometry of the specimen was 50x10x200 (mm). [Pg.195]

Portland cements are available commercially in many different forms, including varieties for high early strength and for sulfate resistance and very finely ground materials called microfines. [Pg.129]

There are four distinctly different types of Portland cement. Only types I and II are used for grouting, type I (often referred to as ordinary Portland cement), almost exclusively. Type II (high early strength cement) differs from type I primarily in its finer particle size. This provides more reactive surface area, and thus more rapid setting, often desirable in structural work. Grouters, however, are more interested in the finer particle size, which permits penetration into finer voids and cracks. Typical grading analysis of various cements are shown in Figure 9.1. [Pg.130]


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See also in sourсe #XX -- [ Pg.403 ]




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