CONCRETE IN HOT ENVIRONMENTS - CHAPTER 2 pot

... Calorimetrier, (19 82) , pp. 2/ 41 2/ 48 (in French). 2. 18. ACI Committee 20 7, Effect of restraint, volume change, and reinforcement on cracking of massive concrete (ACI 20 7.2R–73) (Reaffirmed 1986). In ACI Manual ... accelerated, its initial and final setting Fig. 2. 15. Effect of placing tempera- ture on temperature rise in mass concrete containing 22 3 kg/m 3 of type I c...

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... grains and, thereby, reduce the spacing between the solids. Hence, on subsequent hydration, the resulting capillary pores in the silica-fume- containing paste are much finer than the pores in ... prohibited altogether, in reinforced concrete. The effect of pozzolans and of other admixtures on possible corrosion of the reinforcing steel in concrete is discussed in some detail in...

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... not indicated by the data of Fig. 8.13 implying, in turn, that some other mechanisms may be involved. 8.4 .2. 4. Mineral Admixtures In discussing the effect of mineral admixtures on drying shrinkage ... load, shrinkage occurs simultaneously. Accordingly, creep is the increase in deformation with time under a sustained load excluding drying shrinkage. This is demonstrated in Fig. 8.1 f...

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... 9. 12 in which the intensity of the reaction is measured by the resulting expansion. Indeed, this effect is utilised in determining the potential alkali reactivity of cement-aggregate combinations ... with the alumina-bearing phases of the hydrated cement to give a high- sulphate form of calcium aluminate (3CaO.Al 2 O 3 .3CaSO 4 .32H 2 O, i.e. C 3 A.3CS¯.H 32 ), known as ettringite...

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... Cement 1.1 Introduction 1 .2 Major constituents 1 .2. 1 Alite 1 .2. 2 Belite 1 .2. 3 Tricalcium aluminate 1 .2. 4 Celite 1 .2. 5 Summary 1.3 Minor constituents 1.3.1 Gypsum (CaSO 4 · 2H 2 O) 1.3 .2 Free lime ... Spon 2 Setting and Hardening 2. 1 Introduction 2. 2 The phenomena 2. 3 Hydration 2. 4 Formation of structure 2. 5 Effect of temperature on the hydration process 2. 5.1 Ef...

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... W.H., Factors influencing concrete strength. J. ACI, 47 (2) (1951), 417– 32. 1.9. ACI Committee 22 5, Guide to selection and use of hydraulic cements. (ACI 22 5R-85). In ACI Manual of Concrete Practice ... materials containing lime (CaO), silica (SiO 2 ), alumina (Al 2 O 3 ) and iron oxide (Fe 2 O 3 ), and grinding the resulting clinker with a few percent of gypsum. The cement...

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... May (19 82) , 429 – 32. 4 .20 . Ravina, D., Slump loss of fly ash concrete. Concrete Int., 6(4) (1984) 35–9. 4 .21 . ACI Committee 305, Hot- weather concreting (ACI 305R-89). In ACI Manual of Concrete ... of concrete containing high-range water- reducing admixtures in hot weather. In Development in the Use of Superplasticizers (ACI Spec. Publ. SP 68). ACI, Detroit, MI, USA,...

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... Shrinkage and creep of mortar and concrete as affected by hot humid environment. In Proc. RILEM 2nd Int. Symp. on Concrete and Reinforced Concrete in Hot Countries, Haifa, 1971, Vol. II, Building ... kg/m 3 cement), and 2 and 6 (10 min mixing time, 340 kg/m 3 cement). In fact, the effect of fly-ash was quite significant, increasing, in the case of 10 min mixing, plastic...

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... frame, and steel. All-aluminum gang forms consist of aluminum sheathing supported by an aluminum frame along with intermediate stiffen- ers. The aluminum sheathing can be plain or take the shape ... carry out such work as form stripping and cleaning, setting of reinforce- ment, and other wall maintenance in preparation for the next pour. A 30 in. (7 62 mm) wide working platform also allow...

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... humidities indicated (wind velocity 20 km/h), on shrinkage of concrete containing 350 kg/m 3 ordinary Portland cement. Drying at 20 °C and 50% RH from the age of 28 days to the age of 425 days. ... RILEM 2nd Int. Symp. on Concrete and Reinforced Concrete in Hot Countries, Haifa, 1971, Vol. I. Building Research Station—Technion, Israel, Institute of Technology, Haifa, pp. 309 21 ....

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