Performance of concrete containing high volume coal fly ash - green concrete

Abstract

Concrete is usually the most common element in a building and over the years, many solutions were developed in order to improve its qualities. We conducted a comparison between ordinary Portland cement concrete and high volume coal fly ash concrete, with the fly ash used as a substitute for the cement. Generally accepted, the total binder in a green concrete is composed of 50% cement and 50% fly ash, which is less than 200 kg/m 3 in our case (P. Kumar Mehta -High Performance, high-volume fly ash concrete for sustainable development. University of California, Berkeley, USA). We investigated concrete mixes containing 40% and 50% fly ash as partial replacements of the cement. A C20/25 class concrete was tested at 7, 28, 90 and 365 days of age for: compressive and tensile strength, modulus of elasticity, freeze thaw resistance, water permeability, and shrinkage and bond strength. We found that concrete made with fly ash is a good choice for a medium concrete class with increased durability properties.

A Review of How the Characteristics of Concrete is Altered when Fly Ash is used as a Partial Replacement for Cement

“…This might be because the fly ash enhances the interfacial connection between the aggregate and the paste in a lowvolume fly ash concrete. The fly ash, on the other hand, reduces the interfacial connection between the aggregate and the paste in high-volume fly ash concrete (Dhiyaneshwaran, 2013;Magureanu and Negrutiu, 2009). Table 5 further shows that the splitting tensile strength of all mixtures continued to grow with age (Siddique, 2003).…”

Drop-Weight Impact Response of Fibre Reinforced Cement Based Foams

“…Besides, it helps reduce the water demand for a given consistency [17]. Further in cement based foams fly ash prevents thermal cracking and controls autogenous shrinkage when used as a partial replacement of Port and cement [18,19,201. However, one must caution that fly ash when used at higher dosage (usually as a replacement to the sand) in low density foamed concrete leads to higher shrinkage cracks [21,221.…”

Flexural Behavior of RC Beams by Using Agricultural Waste as a Cement Reinforcement Materials

“…Polymer modified concrete is a latest high performance material to a relative extent, which has extensive applications due to its advantages that make it to be more successful than cement concrete as Ohama, Fowler, Fowler, Reis, Giusca and Magureanu [11][12][13][14][15][16] studied. Most notably advantages put forth by the polymer concrete are: Splendid mechanical strength, rapid curing, having the property of making ingredients to stick together, able to resist the abrasion and weathering, water tightness and giving good results against thermal properties as Magureanu, Muthukumar, Barbuta, Barbuta, Barbuta, Gorninski polymer concrete/polymer modified concrete i.e.…”