CONCRETE IN HOT ENVIRONMENTS - CHAPTER 8 pot

... 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....

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... ‘hardening’. These stages of setting and hardening are schematically described in Fig. 2.1. The initial and final setting times are of practical importance. The initial setting time determines ... length of time in which cement mixes, including concrete, remain plastic and workable, and can be handled and used on the building site. Accordingly, a minimum of 45 min is specified in most...

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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 ... rise measured in mass concrete. Control mix contained 400 kg/m 3 ordinary Portland cement (OPC). In the fly-ash concrete 30% of the OPC was replaced by fly-ash and in the slag concrete...

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... containing Santorin earth. Cement Concrete Res., 11(4) (1 981 ), 507– 18. 9.19. Dunstan, E.R., Performance of lignite and sub-bituminous fly ash in concrete A progress report. Report REC-ERC-76–1, ... 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...

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... and S.Mindess Concrete in the Marine Environment P.K.Mehta Concrete in Hot Environments I.Soroka Durability of Concrete in Cold Climates M.Pigeon and R.Pleau (forthcoming) High Strength Concrete P.C.Aitcin (forthcoming) ... admixtures 7.5 Shrinkage cracking 7.6 Summary and concluding remarks References 8 Creep 8. 1 Introduction 8. 2 The phenomena 8. 3 Creep mechanisms...

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... heterogeneous material made up of several fine-grained minerals which are formed during the clinkering process. Four minerals, namely Alite, Belite, Celite and a calcium-aluminate phase, make up some 90% ... water, hydration takes place bringing about setting and subsequent hardening in a few hours. If not allowed to dry, the resulting solid gains strength with time mainly during the first...

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... on Concrete (ASTM Spec. Tech. Publ., STP 85 8). ASTM, Philadelphia, PA, USA, 1 985 , pp. 66 87 . 4.24. Tipler, T.J., Handling. In Proc. Intern. Seminar on Concrete in Hot Countries. Helsingor, 1 981 , ... May (1 982 ), 429–32. 4.20. Ravina, D., Slump loss of fly ash concrete. Concrete Int., 6(4) (1 984 ) 35–9. 4.21. ACI Committee 305, Hot- weather concreting (ACI 305R -8 9 )....

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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 ... and hardened concrete in the Arabian Gulf environment. Cement Concrete Res., 18( 4) (1 988 ), 561–70. 5.14. Dahl, A.P., Influence of fibre reinforcement on plastic shrinkage...

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... accessible, since the forms can be up to 16 ft (4 .88 m) high and 44 ft (13.41 m) long. Openings/Inserts Jumps forms are best suited to building designs in which the open- ings are regularly occurring ... made of aluminum (all-aluminum), ply- wood face and aluminum frame, plywood face and steel frame, and steel. All-aluminum gang forms consist of aluminum sheathing supported by an aluminum...

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... 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. I. Building Research Station—Technion, ... opposing effect of the corresponding increase in the modulus of elasticity. (3) Joints should be provided in concrete members in order to reduce the restraining...

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