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Every year, tens of millions of the 1.4 billion cars on the world’s roads are decommissioned. While the ferrous and other metals that constitute about 75% of a vehicle by weight can be readily and profitably recycled, the remaining mix of plastics, glass, composites, complex materials, fragments and contaminants are mainly destined for landfill as automotive shredder residue (ASR). For every car, approximately 100–200 kg of ASR is disposed of in landfill, posing a growing technical and environmental challenge worldwide. The recovery of the ASR for high-end application is the focus of this study, aiming to optimise the use of these valuable resources and minimise the extractive pressure for raw materials, a future green manufacturing, contributing towards a zero waste circular economy. As the dissolution of carbon into iron is a key step in the manufacture of iron-carbon alloys, the feasibility of utilizing the waste polymers within ASR as sources of carbon in different areas of pyrometallurgical processing was investigated. Polypropylene and rubber, in a blend with metallurgical coke, were used as carbonaceous substrates and the slag-foaming phenomenon was investigated via the sessile drop technique in an argon environment at 1,550°C. The results indicated the rubber/coke blend achieved significantly better foaming behaviour, and the PP/coke blend exhibited a moderate improvement in slag foaming, in comparison to 100% metallurgical coke. The overall results indicated the incorporation of ASR had significant improvement in foaminess behaviour, increasing furnace efficiency.

The purpose of the study is to present a simplified model to replace the complicated foaming simulations for investigating the liquid polyurethane behavior just before solidification.

This model is inspired from the traveling heater method of crystallization because of the low injection velocity. Besides, the heat generated during the reaction is considered as a heat source function in the energy equation.

Various distributions of the heat generation function inside the geometry have been studied to choose the most realistic one. Effect of parameters such as the soil material and porosity on the temperature distribution and flow field are examined for different values of heat flux on the boundaries. Results show an almost linear dependency of pressure drop to the velocity, a uniform velocity profile and an expected temperature distribution compared to literature, which approves the suggested model.

A new model is presented in this study for foaming which replaces a heat generation function (exponential) in the source term of the energy equation instead of the heat produced at the exit boundary (the solid–liquid interface), and the traveling method is used instead of moving the geometry; besides, the growth ratio has been neglected; therefore, this model has been validated by a foaming simulation to confirm the suggested simplified idea.

In this study, the insulation fire ratings of lightweight foamed concrete, autoclaved aerated concrete and lightweight aggregate concrete were investigated using finite element modelling.

Lightweight aggregate concrete containing various aggregate types, i.e. expanded slag, pumice, expanded clay and expanded shale were studied under standard fire and hydro–carbon fire situations using validated finite element models. Results were used to derive empirical equations for determining the insulation fire ratings of lightweight concrete wall panels.

It was observed that autoclaved aerated concrete and foamed lightweight concrete have better insulation fire ratings compared with lightweight aggregate concrete. Depending on the insulation fire rating requirement of 15%–30% of material saving could be achieved when lightweight aggregate concrete wall panels are replaced with the autoclaved aerated or foamed concrete wall panels. Lightweight aggregate concrete fire performance depends on the type of lightweight aggregate. Lightweight concrete with pumice aggregate showed better fire performance among the normal lightweight aggregate concretes. Material saving of 9%–14% could be obtained when pumice aggregate is used as the lightweight aggregate material. Hydrocarbon fire has shown aggressive effect during the first two hours of fire exposure; hence, wall panels with lesser thickness were adversely affected.

Finding of this study could be used to determine the optimum lightweight concrete wall type and the optimum thickness requirement of the wall panels for a required application.

Concrete is the most basic of building materials and yet, in the hands of the expert, is capable of providing strength, durability and even elegance far in excess of many of its manufactured competitors. The technology is by now well established but the production of concrete of a consistently good quality is by no means simple.

Industrial chimneys are a great part of environmental protection in industrial countries. In recent years many of them have been used to carrying away very aggressive gases from boilers and flue gas desulphurisation (FGD) units below acid dew‐point temperature. It is opf very important to modernize the old stacks and protect them against corrosion. The proper anti‐corrosion protection of modern high stacks is also an important technical and economical problem. In this paper the mechanism of acid dew‐point corrosion, as well as construction of industrial chimneys, methods of their anti‐corrosion protection and modernisation are described.

CORROSION TESTS WITH ULTRASONICS ? IT is well known that the corrosion of iron, zinc, aluminium, magnesium, etc., is slower in moving water than in water at rest. This has been explained by the protective oxide film theory, i.e. the supply of oxygen to the metal surface is more adequate in moving water for the formation of complete films than in water at rest. When ultrasonic waves are used to stir the corroding solution in which the metal is immersed, the wet corrosion may be explained by a colloid science argument rather than by oxide film theory.

Discusses the results of a study of the moduli of elasticity of concretes made with artificially manufactured lightweight aggregates subjected to uniaxial compression and uniaxial tension. Two artificially manufactured lightweight aggregates and one normal weight aggregate (for comparison) were used in the investigation. Concrete mixes designed to have compressive strengths varying from 20 MPa to 60 MPa were used in this study. Presents the results of static and dynamic moduli of elasticity, Poisson′s ratio, ultrasonic pulse velocity, compressive strength and tensile strength tests. Observes that the static modulus of elasticity in tension is nearly equal to the static modulus of elasticity in compression at a stress level of one‐third the ultimate stress. Compressive modulus values are shown to be dependent on the stress level and type of modulus, i.e. either secant or tangent. On the other hand, the tensile modulus is not affected by the stress level. The modulus of elasticity of lightweight aggregate concrete is about 60‐70 per cent of that of normal weight concrete. Compares the test results obtained in this study with research work carried out on other lightweight aggregate concretes by other investigators. Also presents the relationships between static modulus of elasticity, dynamic modulus of elasticity, compressive strength, and Poisson′s ratio, and equations for estimating elastic modulus and Poisson′s ratio.

This paper presents the details of a research study on developing composite masonry blocks using two types of mixes, conventional and lightweight mix, to enhance their fire/bushfire resistance and residual compressive strength.

Composite masonry blocks (390 × 190 × 90 mm) were fabricated using conventional cement–sand mix as the outer layer and lightweight cement–sand–diatomite mix as the inner layer. Material properties were determined, and all the mixes were proportioned by the absolute volume method. After 28 days of curing, density tests, compression tests before and after fire exposure and fire resistance tests of the developed blocks were conducted, and the results were compared with those of conventional cement–sand and cement–sand–diatomite blocks.

Developed composite blocks satisfy density and compressive strength requirements for loadbearing lightweight solid masonry units. Fire resistance of the composite block is –/120/120, and no cracks appeared on the ambient side surface of the block after 3 h of fire exposure. Residual strength of the composite block is higher compared to cement–sand and cement–sand–diatomite blocks and satisfies the loadbearing solid masonry unit strength requirements.

Composite block developed in this research can be suggested as a suitable loadbearing lightweight solid masonry block for several applications in buildings in bushfire prone areas.

Limited studies are available for composite masonry blocks in relation to their fire resistance and residual strength.

Cement can be replaced to reduce the energy consumption and the environmental impact of cement. Also, foamed concrete can be used structurally in residential buildings to reduce weight and improve thermal insulation. To achieve these two goals, this paper aims to investigate the effect of basalt powder as a partial replacement of either cement or sand.

This paper investigates the effect of basalt powder as a partial replacement of either cement or sand on the mechanical properties of foamed concrete used to cast slabs. First, mechanical properties of foamed concrete are tested with and without replacement of basalt. Then, six slabs of different thicknesses and mixes are investigated. The thicknesses considered are 150- and 200-mm slabs. The three mixes used to construct these slabs are foamed concrete with no basalt powder, foamed concrete with replacement of 20% of cement by basalt powder and foamed concrete with replacement of 20% of sand by basalt powder. The flexural behavior of these slabs is investigated.

All the slabs failed in the commonly intended flexural mode. The results show that the basalt powder acted as a strong filler material in the foamed concrete mix based on mechanical properties and flexural behavior. The proposed foamed concrete slabs can be used structurally in residential buildings.

A natural waste material that can be used to promote energy efficiency and reduce emission is basalt. In this paper, basalt powder is suggested to be used due to its chemical composition that is similar to cement. Also, basalt powder is low in cost as it is waste, while basalt aggregate is prepared, and it is only used as filler in paved roads. Accordingly, basalt is partially used instead of cement to reduce the emission of carbon dioxide that results from the cement manufacturing. Also, it is used as a partial alternative to sand which can be considered as a new stronger source as filling material used in the production of concrete.