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ABSTRACT Amorphous fraction, grains defects and the incongruent dissolution of solid solutions (pegmatite, trachyte, and granite) were used to design high strength geopolymer composites with crystalline content in the range [...]

GRAPHICAL ABSTRACT ABSTRACT Alkali activated lightweight mortars, obtained by room temperature activation of coal fly ash, were studied as passive fire protection systems for steel elements. Physical, mechanical and thermal [...]

ABSTRACT Air--and formulated lime mortars with pulverized brick waste were synthesized with addition of two organic waste-based additives: spent cooking oil and albumen. The addition of spent oil in the [...]

ABSTRACT In construction industry, concrete is the largest synthesized material. Aggregate is one of the constituents in concrete. Enormous studies have been conducted concerning the protection of natural resources, finding [...]

ABSTRACT This study investigated the resistance of municipal solid waste incinerator bottom ash geopolymer concrete (BA), Ca[(OH).sub.2]-modified BA, and Portland cement-modified BA against carbonation using the accelerated carbonation test. The [...]

ABSTRACT This paper investigates the shrinkage and creep of self-compacting concrete prepared with coarse and fine recycled concrete aggregates (up to 40% of total amount of aggregates). Physical properties and [...]

ABSTRACT Glass with different chemical compositions, deriving from separate collection, has been used as fine aggregate to formulate cementitious mortars, substituting natural sand. Glass coming from cathode-ray tube monitors, fluorescent [...]

ABSTRACT The suitability of new lime mortars for restorative rendering applications was investigated. Air-, formulated- and hydraulic-lime mortars were synthesized with inclusion of two different types of spent sunflower cooking [...]

In this work, sulfonated asphalt was chosen as an admixture, and the influence of the quantity (1%, 2%, 3%, 4% of the weight of the cement) of sulfonated asphalt on the mechanical properties of hardened cement slurry was studied. Moreover, the micro-morphology and porous structure characteristics were examined using the SEM and nitrogen adsorption-desorption method, respectively. Studies showed that the addition of asphalt had great potential to improve the tensile strength and toughness of cement paste. The tensile strength of cement paste with 3% sulfonated asphalt increased by 45% at 7 days and 17% at 28 days in comparison with that of specimens without sulfonated asphalt. In addition, 2-3% sulfonated asphalt levels were advantageous for improving the toughness of oil well cement paste. Asphalt particles caused crack bending and deflection as well as toughened oil well cement paste. The addition of 3% asphalt had a positive good effect on the pore size distribution in cement paste. The addition of asphalt decreased the compressive and flexural strength of cement paste at the same curing age. The content of 4% asphalt increased the pore size and caused deterioration of the mechanical properties of cement paste. It is necessary to balance the mechanical properties of cement paste and the amount of asphalt in the range 2-3% to be beneficial for this application. Keywords: Sulfonated asphalt Oil well cement paste Mechanical properties Toughness Micro-morphology Porous structure, 1. Introduction Oil well cementing is the process of placing cement slurry in the annulus space between the well casing and the geological formations surrounding to the well bore, from [...]

ABSTRACT This work investigates the effects of the structure, the bulk chemical composition and amount of the aluminosilicate fines on the strength development, pore refinement, water permeability, moisture control capacity [...]

ABSTRACT Alkali activation of fly ash can be considered as one of the more promising alternative systems to traditional hydraulic binders, particularly if the process can be carried out at [...]

ABSTRACT The effects of bulk composition and microstructure on strengthening mechanisms and fracture resistance were investigated for metakaolin based geopolymers. Crack initiation and propagation under mechanical and environmental stresses were [...]

Most soils contain some sulphate in the form of calcium, sodium, potassium and magnesium. They occur in soil or ground water. Because of solubility of calcium sulphate is low, ground [...]