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Low-carbon concrete represents a new direction in mitigating the global warming effects caused by clinker manufacturing. Utilizing Saudi agro-industrial by-products as an alternative to cement is a key support in reducing clinker production and promoting innovation in infrastructure and circular economy concepts, toward decarbonization in the construction industry. The use of fly ash (FA) as a cement alternative has been researched and proven effective in enhancing the durability of FA-based concrete, especially at lower replacement levels. However, at higher replacement levels, a noticeable impediment in mechanical strength indicators limits the use of this material.

In this study, low-carbon concrete mixes were designed by replacing 50% of the cement with FA. Varying ratios of nano-sized glass powder (4 and 6% of cement weight) were used as nanomaterial additives to enhance the mechanical properties and durability of the designed concrete. In addition, a 10% of the mixing water was replaced with EMs dosage.

The results obtained showed a significant positive impact on resistance and durability properties when replacing 10% of the mixing water with effective microorganisms (EMs) broth and incorporating nanomaterial additives. The optimal mix ratios were those designed with 10% EMs and 4–6% nano-sized glass powder additives. However, it can be concluded that advancements in eco-friendly concrete additive technologies have made significant contributions to the development of sophisticated concrete varieties.

This study focused at developing nanomaterial additives from Saudi industrial wastes and at presenting a cost-effective and feasible solution for enhancing the properties of FA-based concrete. It has also been found that the inclusion of EMs contributes effectively to enhancing the concrete's resistance properties.

This study investigates the effect of slag of blast furnace (SL) and sand of dune, (SD) replacement of cement on the durability of cement to chemical aggressive water (acid and sulfates) attack, Tow replacement levels were considered in the study: (5% sand of dune + 15% slag) and (10% sand of dune + 15% slag) by weigh to cement. The other parameters durability investigated in the study were: volumetric stability (shrinkage of drying and swelling), the concrete water permeability. The chemical resistance of cement to the acid and sulfate attack was evaluated by compressive strength reduction of cement specimens were immersed in 5% chloride magnesium and in 5% sodium sulfate solution for a total period of 28 and 90 days. the results obtained show that substitution partial of cement by slag and sand of dune to offer to cement a better stability to the chemical aggressive, and swelling however we noted that the increase in the content of sand of dune of 10% generates a slight increase in shrinkage of drying compared to cement without additions, the water permeability which is an essential characteristic of durability of concrete to be improved specially with partial replacement cement at (5% sand of dune + 15% slag) by weight cement.

Epoxy aluminium adhesive Substantial savings in both capital costs and downtime are now possible because of a new high‐performance aluminium‐filled epoxy adhesive from Devcon UK, Wellingborough.

In England and Wales, the construction industry produces 53.5 Mt of construction and demolition waste (C&D waste) annually, of which 51 percent goes to landfill, 40 percent is used for land reclamation and only 9 percent is crushed for future use or directly recovered. C&D waste may be contaminated, either through spillage from industrial processes or contact with contaminated land. There are no guidelines on how to classify C&D waste as contaminated or on risk management for contaminated C&D waste. Research at the UK Building Research Establishment and the University of Manchester has shown that new taxes are making disposal of C&D waste to landfill uneconomic, that low grade “land‐modelling” recycling is increasing, and that disposal on‐site is preferred. Sampling spatially of structures before demolition and temporally of processed C&D waste emerging from crushers is enabling sources of contamination and exceedance of guideline values to be compared with natural background levels. Improved sampling procedures and recommendations for risk assessment for the re‐use of C&D waste are being prepared.

This study aims to practically determine the optimum proportion of aggregates to attain the desired strength of geopolymer concrete (GPC) and then compare the results using established analytical particle packing methods. The investigation further aims to assess the influence of various amounts of recycled aggregate (RA) on properties of low-calcium fly ash-based GPC of grade M25.

Fine and coarse aggregates were blended in various proportions and the proportion yielding maximum packing density was selected as the optimum proportion and they were compared with analytical models, such as Modified Toufar Model (MTM) and J. D. Dewar Model. RAs for this study were produced in laboratory and they were used in various amounts, namely, 0%, 50% and 100%. 12M NaOH solution was mixed with Na₂SiO₃ in the ratio of 1:2. The curing of concrete was done at the temperatures of 60° and 90 °C for 24, 48 and 72h.

The experimentally obtained optimum proportion of coarse to fine aggregate was 60:40 for all amounts of RA. Meanwhile, MTM and Dewar Model resulted in coarse aggregate to fine aggregates as 40:60, 45:55, 55:45 and 55:45, 35:65, 60:40, respectively, for 0% 100% and 50% RAs. The compressive strength of GPC elevated with the increase in curing regime. In addition, the ultrasonic pulse velocity also displayed a similar trend as that of strength.

The GPC with 50% RAs may be considered for use, as it exhibited superior properties compared to GPC with 100% RAs and was comparable to GPC with natural aggregates. Furthermore, compressive strength is correlated with split tensile strength and ultrasonic pulse velocity.

Generally, of all the properties, corrosion resistance can be a prime consideration in determining whether a given alloy or metal is adequate for a proposed use. With the increasing ability to fabricate many alloys and metals into fibre material of extremely small diameter, a better knowledge of their chemical properties as related to their unique size becomes more essential since many of the potential applications involve exposure to corrosive environments. This article reviews the corrosion resistance of Brunsmet MF‐A1 stainless steel fibres produced by the Brunswick Corp., Chicago, Illinois.

In the manufacture of ammonium sulphate, whether by using evaporators or saturators, the erosive effect of crystals present in solution, the low sulphuric acid concentrations usually present, and the relatively high temperatures of operation give rise to serious corrosion problems which begin at the drawing board stage of design and continue through all stages of manufacture. These corrosion problems are discussed in detail in this article and advice is given on materials of construction, including stainless steels, nickel alloys, rubber‐lined mild steel, lead, silicon irons, aluminium and a number of plastics.

Much progress has been made in the field of corrosion technology in the last few years and many new corrosion‐resisting materials have been developed, including improved types of plastics and metals such as zirconium, titanium and tantalum. Plastics are finding extensive use as lining materials for chemical plant operating at moderate temperatures, but the poor thermal conductivity of most plastics makes them unsuitable for the transfer of heat. The recently developed metals and their alloys are extremely expensive to produce and fabricate and, so far, their use has been confined to certain specialised applications, although full‐scale production of zirconium is being carried out in America, mainly because of the low capacity of the metal for absorbing thermal neutrons. At the moment, however, these metals, because of their high cost, cannot compete commercially on a large scale with the older well‐established corrosion‐resisting alloys such as the high‐silicon iron alloys. The excellent corrosion resistance of the high‐silicon iron alloys, even at high temperatures, and their high thermal conductivity have established them as almost standard alloys for acid concentration and cooling plant construction. The following article outlines their composition and properties.

The purpose of this study is to contribute with experimental study of the effects of binary and ternary combinations of river sand (RS), crushed sand (CS) and dune sand (DS) on the physical and mechanical performances of self-compacting concrete (SCC) subjected to acidic curing environments, HCl and H₂SO₄ solutions.

Five SCCs were prepared with the combinations 100% RS, 0.8RS + 0.2CS, 0.6RS + 0.2CS + 0.2DS, 0.6RS + 0.4DS and 0.6CS + 0.4DS. The porosity of sand, fluidity, deformability, stability, compressive strength and sorptivity coefficient were tested. SCCs cubic specimens with a side length of 10 cm were submerged in HCl and H₂SO₄ acids, wherein the concentration was 5%, for periods of 28, 90 and 180 days. The resistance to acid attack was evaluated by visual examination, mass loss and compressive strength loss.

The results showed that it is possible to partially substitute the RS with CS and DS in the SCC, without strongly affecting the fluidity, deformability, stability, compressive strength and durability against HCl and H₂SO₄ attack. The two combinations, 0.8RS + 0.2CS and 0.6RS + 0.2CS + 0.2DS, improved the compactness and the resistance to acid attacks of SCC. Consequently, the improvement in SCC compactness, by the combination of RS, CS and DS, decreased the sorptivity coefficient of SCC and increased its resistance to acid attacks, in comparison with that made only by RS.

The use of RS is experiencing a considerable increase in line with the development of the country. To satisfy this demand, it is necessary to substitute this sand with other materials more abundant. The use of locally available materials is a very effective way to protect the environment, improve the physico-mechanical properties and durability of SCC and it can be a beneficial economical alternative. Few studies have addressed the effect of the binary and ternary combination of RS, CS and DS on the resistance to acid attacks of SCC.

Tantalum has a resistance to aqueous corrosion that may be compared closely with that of glass. The principal use of the metal is in the construction of chemical plant where its excellent corrosion‐resistant properties have assured a place for it in special applications, particularly where corrosion resistance needs to be combined with a high degree of heat transfer. This sphere of application is expanding rapidly.