Showing papers in "Construction and Building Materials in 2015"

TL;DR: An overview of advances in geopolymers formed by the alkaline activation of aluminosilicates is presented along with opportunities for their use in building construction as mentioned in this paper, with respect to fresh and hardened states, interfacial transition zone between aggregate and geopolymer, bond with steel reinforcing bars and resistance to elevated temperature.

TL;DR: In this article, the theoretical principles, raw materials, mixture design methods, and preparation techniques for UHPC are reviewed, including reduction in porosity, improvement in microstructure, enhancement in homogeneity, and increase in toughness.

TL;DR: Foamed concrete possesses characteristics such as high strength-to-weight ratio and low density as discussed by the authors, which reduces dead loads on the structure and foundation, contributes to energy conservation, and lowers the labor cost during construction.

TL;DR: In this article, the effect of the addition of steel and polypropylene fibers on the mechanical and some durability properties of high-strength concrete (HSC) was investigated, and the results showed that the incorporation of 1% steel fiber significantly enhanced the splitting tensile strength and flexural strength of concrete.

TL;DR: In this article, the theoretical principles, raw materials selection, mixture design and preparation techniques for UHPC were reviewed, including hydration, microstructure, mechanical properties, dimensional stability and durability.

TL;DR: In this paper, the authors provide a comprehensive and updated report on the temperature dependency of such parameters as the compressive strength, modulus of elasticity, strength in indirect tension (bending and splitting tests), stress-strain curves and spalling, but the roles played by the water-binder ratio (w/b), aggregate type, supplementary cementitious materials (SCMs) and fibres are investigated as well.

TL;DR: In this paper, the mechanical properties of two types of commercially available products (scrimber and laminated bamboo sheets) were investigated and compared to wood and engineered timber products, and it was shown that engineered bamboo products have properties comparable to or surpass that of timber and timber-based products.

TL;DR: A review of the research done during the last years in the area of the cement-based composites reinforced with cellulose fibers is presented in this article, where the main achievements found have been the development of durable cement composites with optimized fiber-matrix adhesion.

TL;DR: In this article, a review of the previous work involving mechanical properties of kenaf fibre reinforced polymer composites is presented to provide a perfect source of literature for doing further research in this topic to explore it as construction and building materials.

TL;DR: In this article, the authors present a concise review of the current studies on the utilization of industrial by-products as the primary binder materials in the fabrication of geopolymer concrete.

TL;DR: In this paper, the effect of Xanthan gum on the performance of soil treatment in construction engineering has been investigated and it was shown that the effect depends on the type of soil, hydration level, and mixing method of the soil.

TL;DR: In this article, the effects of some admixtures including silica nanoparticles, silica fume and Class F fly ash on different properties of high performance self compacting concrete (HPSCC) were presented.

TL;DR: In this article, the effects of sodium hydroxide and sodium silicate solutions on the properties of fly ash (FA)-granulated blast furnace slag (GBFS) geopolymer were investigated.

TL;DR: In this paper, the use of agricultural wastes as a supplementary cementitious material in the production of concrete is discussed, with the aim to minimize the negative impact of the concrete industry through the explosive usage of raw materials, the source of which are both reliable and suitable for alternative preventive solutions promotes the environmental sustainability of the industry.

TL;DR: In this article, the authors analyzed the application of basalt and glass fibers as fiber reinforcement in high strength concrete and found that there was no significant effect of fiber inclusion on the compressive strength and modulus of elasticity of concrete.

TL;DR: In this paper, the effects of activator modulus (SiO2/Na2O from 1.0 to 1.8) and slag/fly ash mass ratios (between 90/10 and 50/50) on reaction kinetics, gel characters and compressive strength were investigated.

TL;DR: In this paper, the authors developed a bacteria-based self-healing concrete by adding the microbial selfhealing agent, which has the potential to improve self-repair capacity mainly by bacteria induced mineral precipitations.

TL;DR: The use of macro plastic fibres to reinforce concrete has attracted widespread attention from both scientists and construction industry due to the multiple sustainability benefits they offer, compared to steel fibres and steel reinforcing mesh as mentioned in this paper.

TL;DR: In this article, the microstructure and compressive strength of Portland cement reinforced with multwalled carbon nanotubes (MWCNTs) was investigated, and it was found that the pore size distribution tilted in favor of gel pores, pores that have a positive influence on mechanical strength.

TL;DR: In this article, the authors investigated the transport characteristics of graphene oxide reinforced cement composites that can be translated to concretes made with similar constituents, and showed that incorporation of very low fraction of a graphene oxide (0.01%) can effectively hinder the ingress of chloride ions.

TL;DR: In this paper, the effects of nano-silica/SiO 2 (NS) and nano-limestone/CaCO 3 (NC) on the flowability, strengths and microstructure of ultra-high-performance concrete (UHPC) matrix under different curing conditions were investigated.

TL;DR: In this article, the authors analyzed the durability performance of concrete with recycled aggregates (RA) from construction and demolition waste (CDW) from various locations in Portugal and concluded that the use of RA is highly detrimental.

TL;DR: In this paper, a procedure for generating two-dimensional heterogeneous meso-scale concrete samples is developed, in which the multi-phasic features including the shape, size, volume fraction and spatial distribution of aggregates and pores are randomised.

TL;DR: In this article, a study of the mechanical behavior of 3D printed structures using cementitious powder is presented, in which compressive and flexural tests are conducted to determine the mechanical properties and failure characteristics of such materials.

TL;DR: In this paper, a number of UHPC mixtures with varying steel fiber lengths (8mm (0.31in), 12mm ( 0.47in) and 16mm(0.62in) were tested and the results showed an increase in mechanical properties as the fiber dosage increased.

TL;DR: In this paper, the influence of nano-TiO 2 on the properties of cement-based materials, the hydration process, the compressive strength development, and the drying shrinkage of concrete-like materials with nano-SiO 2 of 25-nm size was investigated.

TL;DR: In this paper, the feasibility of use of unoiled PVA fibers and hybrid polyvinyl alcohol (PVA) fibers in ECC was studied, and the mix proportion was redesigned through parametric analysis.

TL;DR: In this article, high compressive and flexural tensile strength of alkali activated fly ash geopolymer mortars were presented, where NaOH was used as alkali medium that provides high pH value.

TL;DR: In this paper, a critical review on self-compacting concrete (SCC) mixture design methods is presented, which can be classified into five categories including empirical design method, compressive strength method, close aggregate packing method and methods based on statistical factorial model and rheology of paste model.

TL;DR: In this article, the self-healing effect of a crystalline admixture in four types of environmental exposure comparing with a reference concrete was analyzed by means of permeability tests on cracked specimens and physical closing of the crack was observed by optic microscope and quantified through crack geometrical parameters.