This paper aims at investigating the influence of partial replacement of Portland cement with ultrafine fillers compared to limestone powder on the durability and mechanical characteristics of concrete. For this purpose, ultrafine calcium carbonate materials with different specific surface areas of 9.7 and 15.1 m2/g and limestone powder (0.72 m2/g) were used. The results indicate that the ultra...

Organic matter isolated from the Florida Everglades caused a dramatic increase in mercury release (up to 35 μM total dissolved mercury) from cinnabar (HgS), a solid with limited solubility. Hydrophobic (a mixture of both humic and fulvic) acids dissolved more mercury than hydrophilic acids and other nonacid fractions of dissolved organic matter (DOM). Cinnabar dissolution by isolated organic ma...

The present study concerns a development of calcium aluminate cement (CAC) concrete to enhance the durability against an externally chemically aggressive environment, in particular, chloride-induced corrosion. To evaluate the inhibition effect and concrete properties, CAC was partially mixed with ordinary Portland cement (OPC), ranging from 5% to 15%, as a binder. As a result, it was found that...

This study is descriptive - cross sectional and  during  the 8 months from  winter of 2012 to spring and summer 2013 was performed . In this study at first, with preparation and organization the questionnaire, information about  usage, type and functionality of household treatment systems were collected. Then from 20 Household water treatment ،after water treatment, the samples were taken. samp...

The research reported herein studied the permeability of concrete containing recycled-concrete aggregate (RA), superfine phosphorous slag (PHS), and ground granulated blast-furnace slag (GGBS) with and without stress. Test results showed that the chloride diffusion coefficient of RA concrete (RAC) without external loads decreased with time, and the permeability of RAC is much lower than that of...

The role of F− in the corrosion stainless steel at stage occluded cell a mixture chloride, fluoride, and sulfate ions was investigated. A simulated designed using an elaborate rust layer. Composite electrodes were used to monitor variation concentration ions, pH, dissolved oxygen solution. results show that influence on 304 steel, stage, is dependent. When F−/Cl− ratio higher than 2, can be sig...

Concrete is usually highly alkaline (pH around 12), thus protecting reinforcement against corrosion. The occurrence of oxides is favored when the medium pH surrounding the bar is in values near to 9 or lower. Aggressive substances for reinforcements generally enter concrete through its pore structure, and cracks tend to decrease pH, stimulating corrosion process. There are several causes for cr...

This paper presents a study on the behavior of concrete produced from multi-component blended cements. These blends were prepared by blending 20 percent to 60 percent ASTM Type I cement with the combination of Class C fly ash and clean coal ash. Two percent to four percent sodium sulfate anhydrite was added to the blends as a chemical activator. Tests were conducted on the prepared concrete for...

The aim of this work is to investigate how ANFIS modelling of the chloride permeability of concrete can contribute to the sustainable development. Therefore, to have an opinion about service lives of concrete structures, especially the reinforced ones. Thus, some mixture properties and the rapid chloride permeability test results of different types of concretes obtained from a previous study ar...