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In recent decades, geopolymer concrete has often been viewed as an alternative to traditional concrete. Although its comparatively lower production of greenhouse gas emissions during a lifecycle is usually mentioned at the top of the list of benefits, the possibility of using various waste materials in its production is a clear advantage as well. This literature review summarizes and analyses the existing information on the different available construction wastes for the production of geopolymer and foamed geopolymer concrete and analyzes the curing conditions, constituents in the aluminosilicate precursor, mechanical properties, and the activator type. As part of the literature review, the use of autoclaved aerated concrete and brick wastes has been evaluated. Autoclaved concrete has been chosen because it is a typical low-strength, cement-based construction material and demolition waste that is currently disposed of in landfills, making it quite a challenge for direct use as a supplementary cementitious material. On the other hand, brick waste, one of the most common construction wastes, can be feasibly used in the form of brick dust. This literature review uses data from randomly selected studies. [ABSTRACT FROM AUTHOR]

Foamed concrete has been used as a building material since early 1920. In the beginning, it was used as an insulation material with very low density. Since then there have been attempts to make this material more load-bearing and structural. In present-day foamed concrete is being used in soil reinforcement, building blocks and other sorts of building materials [1]. Geopolymer concrete has been around for more than 40 years. It is being used in all sorts of buildings such as railroads, reservoirs, and houses. As both of these materials, structural capacities and usage increases there still are questions regarding their long-term properties like creep and shrinkage. This article aims to determine the differences in the time-dependent long-term properties of these two different building materials. The size of all creep and shrinkage specimens was 46mm in the diameter and 190mm in height. The creep properties of the specimen were determined by loading them with 20% of the ultimate stress value. The compressive strength, creep and shrinkage of both materials were determined. Also, new information on geopolymer concrete and foam concrete specimen modulus of elasticity variation differences in-time were determined. Modulus of elasticity did reach 31.39 GPa on the 30th day, 36.79 GPa on the 62nd and 48.34 GPa on the 135th day since specimens were made for geopolymer concrete and 12.22 GPa on the 30th day, 12.49 GPa on the 62nd and 14.23 GPa on the 135th day since specimens were made for foam concrete. All the data regarding compressive strength, long-term properties, and modulus of elasticity of the specimens have been obtained by experimental investigation only. [ABSTRACT FROM AUTHOR]

Foamed concrete has been used as a building material since the early 1920s. In the beginning, it was used as an insulation material with very low density. Since then there have been attempts to improve the structural properties in order to increase materials load-bearing capacity. In the present-day foamed concrete is being used in soil reinforcement, manufacturing of building blocks and other sorts of construction materials (Mugahed Amran, Farzadnia, & Abang Ali, 2015). The aim of this article is to determine the behaviour and long-term properties of foamed concrete. Cylindrical specimens (Ø46×190 mm) were used for creep and shrinkage testing. The creep properties of the specimens were determined by loading them with 20% and 60% of the ultimate compressive stress value (Sprince, 2015). The compressive strength, creep, shrinkage and specific creep of the material were examined. It was determined that during 90 days of creep testing the non-linear creep deformations (specimens loaded with 60% of the ultimate stress) are 4 times larger than linear creep deformations (specimens loaded with 20% of the ultimate stress). Also, changes in the modulus of elasticity of foamed concrete were researched over time. Foamed concrete modulus of elasticity reached 12.21 GPa on the 28th day, 12.49 GPa on the 62nd and 14.23 GPa on the 144th day since the specimens were made. [ABSTRACT FROM AUTHOR]