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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]

The challenge of the present investigation is to evaluate the possibility of using micro- and nano- fillers as active additives in concrete composition for the replacement of cement and elaborating a new concrete. This paper examines experimental test results carried out with the aim to evaluate the long-term deformations - creep of elaborated concrete composition. Two kinds of fiber-reinforced high performance concrete mixes using those additives and a cocktail of polyvinyl alcohol (PVA) fibers have been developed and prepared. The cubes and cylindrical specimens were prepared for each composition and tested. Cylindrical specimens were put into a creep lever test stand and subjected to a uniform compressive load kept constant over a long period in constant room temperature and level of moisture. This study was carried out in two different extreme environments: in one case they were kept in 100% humidity ensured by preventing the desiccation of the concrete and in the other case samples were air-dried. Compressive strength and modulus of elasticity were determined for each concrete composition. The results of the experiments allow the authors to predict long-term deformations of the concrete. [ABSTRACT FROM AUTHOR]