Showing papers in "Advanced Cement Based Materials in 1997"

TL;DR: In this paper, the authors used a model of concrete in which the aggregates are spherical, but with an arbitrary size distribution, to accurately give the total interfacial transition zone (ITZ) volume for any width ITZ and any volume fraction of aggregates.

TL;DR: Raman spectra of single-phase calcium-silicate hydrate (C-S-H) samples with C/S ratios between 0.88 and 1.45 are consistent with a defect tobermorite model for the structure of these materials, in agreement with previously published nuclear magnetic resonance (NMR) spectroscopic data for the same samples.

TL;DR: In this article, a review deals with the recent progress of developments in concrete-polymer composites, which are classified into three types: polymer-modified (or cement) mortar (PMM) and concrete (PMC), polymer mortar and concrete, and polymer-impregnated concrete (PIC).

TL;DR: The properties of the fiber/matrix interface are of primary significance for the overall behavior of fiber reinforced cement based composites as discussed by the authors, and an overview of the current knowledge regarding characterization and engineering of the interface is given.

TL;DR: In this article, three different series of mortars with variable sand volume contents were cast in two different laboratories to study the influence of the interfacial transition zones (ITZ) on the transport coefficient of chloride ions.

TL;DR: In this paper, the interaction mechanisms of the cement paste hydration products with chloride were investigated for various systems, including water/binder ratio (0.25 and 0.45), type of cement (ASTM type I, III, and V), use of silica fume (6%), and chemical composition of the chloride solution.

TL;DR: In this paper, the authors introduce a new type of high performance concrete, which replaces 25% by volume of the aggregates by prewetted lightweight aggregates, which creates water storage inside the concrete and supports continuous wet curing.

TL;DR: In this article, analytical modeling of chloride diffusion is used to study the relative influence of the skin thickness on the relative concentration of chloride in the cover of a concrete cover of reinforcements, and it is shown that if the diffusivity of the surface skin and the bulk concrete are very different, an error is introduced when the skin effect is not accounted for.

TL;DR: In this paper, the authors present an experimental investigation on the hot-water durability of glass fiber reinforced cement composites (GFRC) and show that the blended cement consisting of synthetic pozzolan metakaolin significantly improves the durability of GFRC composite.

TL;DR: In this article, the effectiveness of transition zone densification on the fiber-cement paste system was investigated, and it was concluded that the transition-zone densification technique should be effective in fiber-cement systems in which bond strength is controlled by cohesive failure of the transition zone material.

TL;DR: The early strength development of ordinary Portland cement (OPC)/calcium aluminate cement (CAC) pastes (92.5/7.5, 80/20, and 20/80) was studied in this paper.

TL;DR: In this paper, a computationally efficient method for analyzing the performance of short-fiber reinforcement in cementitious composites is presented, where each fiber is modeled as a discrete entity.

TL;DR: In this paper, the DLVO theory and relevant basic concepts are reviewed and applied to determine the state of floculation for cement pastes, and it is shown that normal, neat cement suspensions are either flocculated or coagulated.

TL;DR: In this paper, a new testing method has been developed which yields pure mode II, which can be used in predicting a size effect in concrete members under shear action, which is demonstrated by numerical analysis as well as by analytical treatment.

TL;DR: In this article, the effect of both initial temperature and subsequent high curing temperature on the degree of hydration of normal strength concrete at the age of 28 days was investigated through a difference in the hydration state in relation with the initial mixing and curing conditions.

TL;DR: In this article, controlled rate thermal analysis (CRTA) was applied to the thermal curing of a reactive powder concrete, which was adjusted to keep the rate of gas evolution constant and in dynamic equilibrium at a pressure of 3 Pa.

TL;DR: In this article, the peak-load method was applied to splitting tension tests to determine fracture parameters of the two-parameter fracture model from the measured peak loads, and the results showed that a hole drilled at the axis of splitting tension cylinder can largely expand the specimen distinction.

TL;DR: In this article, the authors investigated the rebar-concrete interface properties by conducting the single rebar pullout test using a combination of the stress approach and fracture mechanical theory, the corresponding material parameters were obtained and the model was verified as being suitable for reinforced concrete composite material Advanced Cement Based Materials 1997, 5, 57-65

TL;DR: In this article, a model system consisting of a polycarbonate box with electrodes at each end, divided into two compartments by a poly-carbonate barrier with a single hole, and filled with electrolyte solution, simulates the impedance response in young cement pastes.

TL;DR: In this paper, a filament winding system was developed for manufacturing cross-ply cement based composites using continuous fibers, which was used for manufacturing composite laminates, pipes, and pultruded sections.

TL;DR: In this paper, the degradation of shredded rubber immersed in different chemicals was monitored by observing the changes in mass, swelling, tensile strength, and microstructure of the rubber.

TL;DR: In this article, the porosity and relative humidity in the pores of hardened cement paste were measured and the measured results showed a strong relationship between porosity of the cement paste and the moisture permeability.

TL;DR: In this article, a set of equations based on mass and energy balance are presented to predict when reinforcement corrosion induced by deleterious substances reaching the embedded reinforcement bars, where the flow properties of the pollutant in concrete must be known.

TL;DR: In this article, a new analytical model for predicting the elastic modulus of discontinuous fiber reinforced cement composites in uniaxial tension is presented, which depends on the macroscopic and microstructural parameters (interfacial bond modulus, matrix porosity, and so forth).

TL;DR: In this article, the chemical characteristics of a calcium aluminate-phenol resin composite with very high flexural strength are discussed and a cross-linking mechanism assumed to occur in processing and during curing is proposed.

TL;DR: In this paper, the influence of microwave treatment on the properties of glass-fiber reinforced composites was examined by means of three-point flexure tests and microstructure analysis using differential thermal analysis, infrared spectrometry, and scanning electron microscopy.

TL;DR: In this paper, the authors used the boiling water procedure of ASTM C 684 to evaluate this test method for use in the routine quality control of concrete made of local materials with particular emphasis on the use of blended cements and in the prediction of potential quality and strength of concrete at later ages.

TL;DR: In this article, microstructural change of hardened cement paste and mortar under various stresses was studied to obtain the basic data for judging the safety of concrete structure repeatedly receiving the stress.