Effect of Combined Different Sources of Alumina Silicate on Mechanical Properties and Carbonation Depth of Environmentally Friendly Geopolymeric Composite Based on Metakaolin

Abstract

Today, concrete is the most widely used building material. Cement production releases about 7% of carbon dioxide gas into the atmosphere and increases greenhouse gases, so it seems necessary to use an alternative to Portland cement. In recent years, geopolymers (mineral polymers) have been proposed as a new environmentally friendly cement. Metakaolin, bentonite, zeolite, iron blast furnace slag and fly ash can be mentioned as aluminosilicate sources. In the field of geopolymer concrete construction, few articles have been working on the composition and effect of replacing aluminosilicate sources. In this experimental study, the effect of replacing slag aluminosilicate sources, class F fly ash and bentonite with proportions of 5-45% with metakaolin on the mechanical properties and durability of geopolymer concrete based on metakaolin was investigated. After making the samples, compressive, bending, tensile and carbonation tests were performed on the geopolymer concrete samples to obtain the optimal strength and carbonation depth of the samples. Also, to determine the validity of the tests, machine learning estimation analysis was performed on the samples. The findings showed that bentonite leads to a decrease in strength, while fly ash and slag lead to an increase in strength. The predicted R 2 values showed the highest matching of the correlation matrix (more than 93%) for the pressure samples. In addition, the results of the tests showed that the metakaolin-based geopolymer concrete sample replaced with fly ash (35%) had a lower penetration depth (carbonation) and higher mechanical properties than other samples.

Behavior of Reinforced Geopolymer Concrete Beams under Repeated Load

“…*Corresponding Author Email: hussein.shaker@qu.edu.iq (H. Raad Shaker) Ordinary Portland Cement (OPC) plays a vital function in the production of concrete and the manufacturing of cement involves burning of huge quantities of fuel and breakdown of limestone, which results in large emission of carbon dioxide to the atmosphere (2). The production of one ton of Portland cement causes the release of approximately one ton of carbon dioxide into the environment and the consumption of 1.5 tons of raw materials in manufacturing one ton of cement (3). Another essential reason pushed the engineers to look for another construction material which is a catastrophic fires occurs in France in 1973, which led Davidovits to think in another non-flammable and non-combustible material (4).…”

Self-healing Concrete Using Microcapsules Containing Mineral Salts

“…Based on a brief literature review, it has been found that multicomponent concrete with several additives has emerged as a new generation of concrete that is able to maintain the required properties in all operating conditions. The use of multicomponent concretes is growing due to their ability to manage structure formation and show directed quality in properties at all stages of technology (27,28). For example, Balamuralikrishnan et al (29) analyzed the flexural, shear, and combined effects of the flexural and shear behavior of reinforced concrete beams that were strengthened with externally bonded ferrocement laminates made with spent catalysts.…”