Showing papers in "Cement and Concrete Research in 2004"
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TL;DR: In this paper, the authors discuss the practicality of replacing portland cements with alternative hydraulic cements that could result in lower total CO 2 emissions per unit volume of concrete of equivalent performance.
1,521 citations
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TL;DR: In this paper, a two types of calcium-silicate-hydrate (C-S-H) exist in cement-based materials, but less is known about how the two types affect the mechanical properties.
960 citations
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TL;DR: In this article, the applicability of the tobermorite-jennite (T/J) and T/CH viewpoints for the nanostructure of C-S-H present in real cement pastes is discussed.
847 citations
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TL;DR: In this paper, a family of solubility curves for poorly crystalline calcium silicate hydrate (C-S-H) phases were derived from 29Si magic-angle spinning (MAS) NMR data and by charge balance calculations.
715 citations
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TL;DR: In this paper, the thermodynamic and kinetic factors influencing crystallization pressure are reviewed for cases including capillary rise and evaporation, cyclic wetting and drying, and hydration of cement.
714 citations
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TL;DR: In this article, the influence of moisture states of natural and recycled aggregates on the properties of fresh and hardened concretes was investigated, and the results suggested that an AD aggregate that contains not more than 50% recycled aggregate is optimum for producing normal strength recycled aggregate concrete.
678 citations
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TL;DR: Sulfate attack is defined as deleterious action involving sulfate ions; if the reaction is physical, then, it is physical sulfate attack that takes place as discussed by the authors.
609 citations
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TL;DR: In this article, the properties of high-volume fly ash high-strength concrete incorporating nano-SiO2 (SHFAC) were compared with those of control Portland cement concrete (PCC) and of high volume fly-ash high strength concrete (HFAC) based on short and long-term performance.
606 citations
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TL;DR: In this article, a fine glass powder (GLP) was used for incorporation into concrete as a pozzolanic material to suppress the alkali reactivity of coarser glass particles as well as that of natural reactive aggregates.
544 citations
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TL;DR: In this paper, waste glass is used as coarse aggregates in the concrete and shown to have no significant effect on the workability and strength of the concrete with fresh and hardened concrete tests.
513 citations
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TL;DR: In this paper, a review relates to the models describing the structural evolution of calcium silicate hydrate (C-S-H) at the crystal-chemical level as a function of composition in terms of calcium to silicon ratio.
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TL;DR: In this paper, the results of an experimental investigation dealing with concrete incorporating high volumes of Class F fly ash Portland cement was replaced with three percentages (40, 45, and 50%) of Class-F fly ash Tests were performed for fresh concrete properties: slump, air content, unit weight, and temperature Compressive, splitting tensile, and flexural strengths, modulus of elasticity, and abrasion resistance were determined up to 365 days of testing.
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TL;DR: In this paper, the mechanical properties and self-monitoring capability of nano-SiO2 or nano-Fe2O3 were experimentally studied and compared with that of plain cement paste.
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TL;DR: In this article, an extension of this technique to a pilot study of the hydration of a typical Portland cement was described. But the results were compared with independent measures of the same materials by the analysis of backscattered electron images (BSE/IA) and thermogravimetric analysis.
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TL;DR: In this article, pullout tests were carried out to evaluate the effects of corrosion on bond and bond-slip behavior, for a series of specimens with varying reinforcement corrosion levels between 0% and 9%, and for specimens with and without stirrups that provide confinement.
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TL;DR: In this paper, the effect of silica fume on the bond characteristics of steel fiber in matrix of reactive powder concrete (RPC), including bond strength, pullout energy, etc., are presented.
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TL;DR: In this paper, the possibilities of recycling waste glasses (crushed waste glasses from Korea such as amber, emerald green, flint, and mixed glass) as fine aggregates for concrete were analyzed through basic experimental research.
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TL;DR: In this article, the physical and mechanical properties along with their freeze-thaw durability of concrete produced with concrete aggregates were investigated and test results presented, and it was observed that the unit weight, workability, and durability of the concretes produced through WCA decreased in inverse proportion to their endurance for the freezing and thaw cycle.
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TL;DR: In this article, the influence of fineness of fly ash on water demand and some of the properties of hardened mortar are examined and it is suggested that the fine fly ash is more reactive and its use resulted in a denser cement matrix and better mechanical properties of mortar.
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TL;DR: In this paper, the authors introduce a set of relationships linking the distribution of reinforcement corrosion and the width of cover crack that results from such corrosion, based on experimental results obtained on the longitudinal reinforcements of two beams naturally corroded over periods of 14 and 17 years.
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TL;DR: In this paper, the mix design nomogram (MDN) is used to compare properties and behaviors of different concretes, and the results show that the family concrete with the highest pore volume and with the same compressive strength of 20, 30, and 40 MPa (2900, 4350, and 5800 psi) did not always correspond to the concrete family with high degree of carbonation.
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TL;DR: In this article, a test program was carried out to develop information about the mechanical properties of rubberized concretes with and without silica fume, which were obtained by partially replacing the aggregate with rubber contents varying from 2.5% to 50% by total aggregate volume.
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TL;DR: In this article, the effects of elevated temperatures on the compressive strength stress-strain relationship (stiffness) and energy absorption capacities (toughness) of concretes are presented.
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TL;DR: In this paper, the relationship between the composition of pore solution in alkali-activated slag cement (AAS) pastes activated with different alkaline activators, and the composition and structure of the main reaction products has been studied.
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TL;DR: In this article, the effect of waste tire resources (car tires or truck tires) on the strength and stiffness of concrete was evaluated experimentally, and a hybrid fiber reinforcement using waste tire fiber and polypropylene (PP) fiber was also investigated.
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TL;DR: In this article, the complex nature of recycled concrete aggregates that are susceptible to damage due to recycling was evaluated using microstructural assessment techniques beyond the standard testing methods normally specified for aggregates.
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TL;DR: In this article, the residual strength of HSC and hybrid-fiber-reinforced high-strength concrete (HFRHSC) after exposure to high temperatures was investigated.
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TL;DR: In this paper, the effects of hydrating a white Portland cement (wPc) in 030 and 050 M solutions of sodium aluminate (NaAlO2) at 5 and 20 °C were investigated by 27Al and 29Si magic-angle spinning (MAS) NMR spectroscopy.
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TL;DR: In this article, the compressive strength and ultrasonic pulse velocity (UPV) of concrete with high-volume fly ash (FA), blast furnace slag (BFS), and FA+BFS were evaluated at 3, 7, 28, and 120-day curing period.
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TL;DR: In this paper, the authors present four innovative utilizations of calcium sulfoaluminate (CSA) cement: development of concrete with high early strength: 40 MPa, 6 h after its preparation, and higher than 55 MPa after 24 h.