Search Results (3)

This research was conducted to analyse the possibility of using raw, untreated recycled tyre fibres as an effective concrete reinforcement according to circular economy principles. The aim of the article was also to develop a method for dispensing tire fibres on a real scale. Additional treatment and homogenisation of recycled steel fibres entail higher energy consumption, emissions of greenhouse gases, and increased costs. However, obtaining durable and safe concrete effectively reinforced with steel fibres is critical. Finding a balance between environmental friendliness and product durability is a circular economic challenge. Reference concrete with commercial steel fibres (15 kg/m³) and two concretes containing various quantities of non-treated, raw tyre recycled fibres (25 kg/m³ and 45 kg/m³) were industrially produced. Tests were carried out on the properties of the concrete mixture and hardened concrete, such as compressive strength, flexural strength, splitting strength, modulus of elasticity, residual flexural tensile strength, and fibre distribution in concrete. Tests revealed that increasing the amount of raw tyre fibres disturbs the structure and causes air entrainment and the formation of fibre clusters. Smaller quantities of raw tyre fibres turn out an effective concrete reinforcement. The use of non-treated tyre fibres as concrete reinforcement is possible but requires more stringent control of the concrete parameters. Implementation tests on an industrial scale are a novelty in this study, presenting an analysis of the possible dispensing of tyre fibres in a ready-mixed concrete production plant and testing the characteristics of manufactured concrete. Full article

The building sector is currently undergoing a process of change due to concerns about the sustainability of the construction industry. The application of circular economy criteria to develop new, more sustainable construction products has become one of the major challenges for the society of the future. This research advances towards the development of new lightened gypsum composites that incorporate waste from end-of-life tyres and recycled fibres from mineral wool thermal insulation in their composition. The results show how it is possible to reduce the consumption of the original raw materials by replacing them with recycled rubber granular particles, developing new construction products that are lighter, with better water resistance and greater thermal resistance. Additionally, it is shown that the incorporation of recycled fibres from rock wool and glass wool insulation is a good solution to improve the mechanical resistance of lightened gypsum composites, giving these construction and demolition wastes a second useful life by reincorporating them in the process of manufacturing new prefabricated housing products. Full article

Unfortunately, the production of cement impacts pessimistically on environments since it emits CO₂—a principal Green House Gas (GHG)—encouraging the earth-heating dilemma. Moreover, it necessitates not only high temperature produced by the devouring of narrow natural mineral coal resources to obtain very high amounts of energy, but it also gulps down natural limestone deposits as a raw material that is found confined in nature to obtain intense energy. Quite recently, geopolymerisation—an exothermic process, through which geopolymeric binders can be produced by synthesis of a pozzolanic precursor rich in Alumina and Silica, for an instant, Fly Ash, with alkali solution for activation in an alkali medium at a low temperature and low operational energy—is recognized as a brilliantly promising alternative to conventional cement. That means, no elevated temperature and higher energy consuming reactions are essential any more as found associated with contemporary cement production. This research paper moves towards fulfilling the performance evaluation of durability studies viz., water permeability, sorptivity, sulphate resistance, acid resistance, salt resistance, chloride diffusion, drying shrinkage, and corrosion of fly ash based user and eco-friendly rubberized (containing rubber tyre fibres) geopolymer concrete. Comparisons of the outcomes have been made with its counterpart, which has unearthed that Rubberized Geopolymer Concrete proved to better concerning all the above-mentioned parameters than Rubberized OPC-Concrete. Full article