Portland cement for high-temperature geothermal applications typically includes 35 to 40 percent crystalline quartz by weight of cement (BWOC) to avoid strength retrogression, which is defined as an increase in permeability and a decrease in compressive strength. Also, because of the reactivity of Portland cement at elevated temperatures, relatively expensive cement-hydration retarders are requ...

Cement-based materials have often been used for infrastructure construction and repair. The production of conventional Portland cement is energy-consuming and environmentally unfriendly. For example, production of one ton of Portland cement generates approximately one ton of carbon dioxide (CO 2 ) from calcining limestone and fuel use. It is estimated that cement production contributes 7% of to...

The climatic change such as the global warming is one of important international problem. On field construction materials, environmental-conscious concrete which are CO2 reduction from materials advance development and practical application. Mostly these techniques use equivalent for type C blended cement that used a large amount mineral admixtures substitution cement. However, only underground...

Copolymer latexes based on 2-hydroxy ethyl acrylate (2-HEA) and 2-hydroxy ethylmethacrylate (2HEMA) were synthesized with different molar ratios (95/ 05, 90/10 and 85/15) using azo-bisisobutyronitril(ABIN) as initiator and alcoholic solution as solvent. Different molar ratios of monomers was designed to investigate the effect of latexes on the physico-mechanical properties of Portland cement mo...

A rapid, reliable and accurate method for the determination of hexavalent chromium in Portland cement is developed. The proposed method includes direct spectrophotometric determination of Cr (VI) in Portland cement with 1, 2, 5, 8 Tetrahydroxyanthraquinone, (Quinalizarin, QINZ) at pH 1.5. The European Directive (2003/53/EC) limits the use of cements so that it contains no more than 2 mg·Kg of w...

This study was carried out in 2011 to investigate the suitability of date palm midribs (Phoenix dactelifera L.) as a lignocellulosic material for the production of wood-cement composite panels, in addition to enhancement their compatibility with cement using various pretreatments and chemical additives. Materials used for this study were midribs of fronds of different date palm varieties availa...

Properties of cement pastes with fine-ground ceramics used as an alternative binder replacing Portland cement up to 20% of its mass are investigated. At first, the particle size distribution of cement and fine-ground ceramics is measured using laser analyser. Then, the material properties are studied in the early hardening period up to 28 days. The hydration process of studied materials is moni...

This paper deals with the issues of air entraining and water/cement ratio in Portland Cement Concrete as related to its freeze thaw durability. Practices have been in place for nearly thirty years which demanded high early strengths in Portland Cement Concrete pavements. This paper looks at those practices, investigates the correlation between water/cement ratio and air entraining, and presents...

AIM To evaluate the biocompatibility of mineral trioxide aggregate and accelerated Portland cement and their eluants by assessing cell metabolic function and proliferation. METHODOLOGY The chemical constitution of grey and white Portland cement, grey and white mineral trioxide aggregate (MTA) and accelerated Portland cement produced by excluding gypsum from the manufacturing process (Aalborg ...