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The purpose of this paper is to study and analyze the effects of fly ash (FA) as a mineral admixture on compressive strength (CS), carbonation resistance and corrosion resistance of reinforced concrete (RC). In addition, the utilization of inexpensive and abundantly available FA as a cement replacement in concrete has several benefits including reduced OPC usage and elimination of the FA disposal problem.

Reinforcement corrosion and carbonation significantly affect the strength and durability of the RC structures. Also, the utilization of FA as green corrosion inhibitors, which are nontoxic and environmentally friendly alternatives. This review discusses the effects of FA on the mechanical characteristics of concrete. Also, this review analyzes the impact of FA as a partial replacement of cement in concrete and its effect on the depth of carbonation in concrete elements and the corrosion rate of embedded steel as well as the chemical composition and microstructure (X-ray diffraction analysis and scanning electron microscopy) of FA concrete were also reviewed.

This review provides a clear analysis of the available study, providing a thorough overview of the current state of knowledge on this topic. Regarding concrete CS, the findings indicate that the incorporation of FA often leads to a loss in early-age strength. However, as the curing period increased, the strength of fly ash concrete (FAC) increased with or even surpassed that of conventional concrete. Analysis of the accelerated carbonation test revealed that incorporating FA into the concrete mix led to a shallower carbonation depth and slower diffusion of carbon dioxide (CO₂) into the concrete. Furthermore, the half-cell potential test shows that the inclusion of FA increases the durability of RC by slowing the rate of steel-reinforcement corrosion.

This systematic review analyzes a wide range of existing studies on the topic, providing a comprehensive overview of the research conducted so far. This review intends to critically assess the enhancements in mechanical and durability attributes (such as CS, carbonation and corrosion resistance) of FAC and FA-RC. This systematic review has practical implications for the construction and engineering industries. This can support engineers and designers in making informed decisions regarding the use of FA in concrete mixtures, considering both its benefits and potential drawbacks.

The purpose of this study is to examine how well reinforced concrete structures can be shielded against concrete carbonation using anti-carbonation coatings based on synthetic polymer.

Applying free radical polymerization, an acrylate terpolymer emulsion that a surfactant had stabilized was created. A thermogravimetric analysis, minimum film-forming temperature, Fourier transform infrared spectroscopy and particle size distribution are used to characterize the prepared eco-friendly water base acrylate terpolymer emulsion. Using three different percentages of the acrylate terpolymer emulsion produced, 35%, 45% and 55%, the anti-carbonation coating was formed. Tensile strength, tensile strain, elongation, crack-bridging ability, carbon dioxide permeability, chloride ion diffusion, average pull-off adhesion strength, water vapor transmission, gloss, wet scrub resistance, QUV/weathering and storage stability are the characteristics of the anti-carbonation coating.

The formulated acrylate terpolymer emulsion enhances anti-carbonation coating performance in CO₂ permeability, Cl-diffusion, crack bridging, pull-off adhesion strength and water vapor transmission. The formed coating based on the formulated acrylate terpolymer emulsion performed better than its commercial counterpart.

To protect the steel embedded in concrete from corrosion and increase the life span of concrete, the surface of cement is treated with an anti-carbonation coating based on synthetic acrylate terpolymer emulsion.

In addition to saving lives from building collapse, it maintains the infrastructure for the long run.

The anti-carbonation coating, which is based on the synthetic acrylate terpolymer emulsion, is environmentally benign and stops the entry of carbon dioxide and chlorides, which are the main causes of steel corrosion in concrete.

This paper aims to assess the suitability of cement combination containing CEM I, fly ash, silica fume and metakaolin for durability design against carbonation-induced corrosion in concrete.

Cube compressive strengths at 28 days and accelerated carbonation depths at 28 days and at various exposure ages were determined at the water/cement ratios of 0.35, 0.50 and 0.65. To assess their suitability for carbonation-induced corrosion, the material costs and embodied carbon dioxide (eCO₂) contents of the concretes at equivalent performance were compared.

Cement combination concretes achieved equal carbonation resistance with CEM I at higher compressive strengths, lower water/cement ratios and higher cement contents. The comparison of the concretes, at equivalent performance, based on the carbonation-induced corrosion exposure classes XC3 and XC4 (Table A.4 of BS 8500-1), shows that ternary and more binary cement concretes have lower costs and eCO₂ contents than those recommended in Table A.6 of BS 8500-1.

This analysis is limited to a working life of 50 years. Further research is needed to verify the suitability of the cement combinations for a working life of 100 years and for the other aspects of durability design covered in BS 8500.

Cement combination concretes have lower eCO₂ content. Hence, when they are cheaper than CEM I concrete at equivalent performance, they would make concrete construction more economic and environmentally compatible.

This research suggests the inclusion of metakaolin and ternary cement combination concretes in BS 8500 for durability design against carbonation-induced corrosion.

This paper aims to investigate the use of calcined mussel shell (CMS) ash–cement mix in concrete that is found to increase the concrete resistance against carbonation.

The deposited ash from the calcination of the mussel shells at 1000°C was used to replace the ordinary Portland cement at 5 and 7 per cent of the cement weight. The test results from the control concrete specimens were compared to the test results from the experimental concrete specimens to analyse the effects due to the said replacements. Carbonation was carried out naturally in the environment where the concentration of the carbon dioxide gas was at 0.03 per cent, the relative humidity of 65 per cent and the temperature of 27°C for a maximum period of 120 days. Measurement of carbonation depth was taken in accordance to the BS EN 13295: 2004. The carbonation resistance of the concrete was assessed based on the degree of compliance with the common design life requirement of 50 years. The filler effect from the CMS was verified using the capillary absorption test (ASTM C1585: 2013) and the electron microscope.

Experimental concrete specimens containing 5 and 7 per cent of the CMS ash demonstrated better carbonation resistance compared to the control concrete specimens with a minimum attainable design life of 56 years which can reach a maximum of 62 years. Capillary absorption test results indicated that the concrete pores have been effected by the said filler effect and visual observation from the electron microscope confirmed, solidifying the statement.

The CMS ash is proven to contribute to the concrete’s resistance against carbonation. Also, the CMS ash is synthesized from waste materials which have contributed to the application of the green material in the concrete technology.

Construction contractors and facility managers are being challenged to minimize the carbon footprint. Life cycle carbon‐equivalent (CO₂‐e) accounting, whereby the potential emissions of greenhouse gases due to energy expenditure during construction and subsequent occupation of built infrastructure, generally ceases at the end of the service life. However, following demolition, recycling of demolition waste that becomes incorporated into 2nd generation construction is seldom considered within the management of the carbon footprint. This paper aims to focus on built concrete infrastructure, particularly the ability of recycled concrete to chemically react with airborne CO₂, thereby significantly influencing CO₂‐e estimates.

CO₂‐e estimates were made in accordance with the methodology outlined in the Australian National Greenhouse Accounts (NGA) Factors and were based on the energy expended for each life cycle activity from audited records. Offsets to the CO₂‐e estimates were based on the documented ability of concrete to chemically react with airborne carbon dioxide (“carbonation”) and predictions of CO₂ uptake by concrete and recycled concrete was made using existing predictive diffusion models. The author's study focused on a built concrete bridge which was demolished and recycled at the end of the service life, and the recycled concrete was utilized towards 2nd generation construction. The sensitivity of CO₂‐e and carbonation estimates were tested on several different types of source demolition waste as well as subsequent construction applications using recycled concrete (RCA). Whole‐of‐life CO₂‐e estimates, including carbonation of RCA over the 1st and 2nd generations, were estimated and contrasted with conventional carbon footprints that end at the conclusion of the 1st generation.

Following demolition, CO₂ capture by RCA is significant due to the more permeable nature of the crushed RCA compared with the original built infrastructure. RCA also has considerably greater exposed surface area, relative to volume, than a built concrete structure, and therefore more highly exposed surface to react with CO₂: it therefore carbonates more comprehensively. CO₂‐e estimates can be offset by as much as 55‐65 per cent when including the contribution of carbonation of RCA built within 2nd generation infrastructure. Further offsets are achievable using blended fly ash or slag cement binders; however, this study has focused on concrete composed of 100 per cent OPC binders and the effects of RCA.

Construction project estimates of life cycle CO₂‐e emissions should include 2nd generation applications that follow the demolition of the 1st generation infrastructure. Life cycle estimates generally end at the time of demolition. However, by incorporating the recycled concrete demolition waste into the construction of 2nd generation infrastructure, the estimated CO₂‐e is significantly offset during the 2nd generation life cycle by chemical uptake of CO₂ (carbonation). This paper provides an approach towards inclusion of 2nd generation construction applications into whole‐of‐life estimates of CO₂‐e.

This study aims to the framework of the development of a new sand concrete, essentially manufactured with river/dune sand and recycled plastic aggregates (PAs; 0/3.15 mm). This new concrete may have a great interest, as it can enable us to achieve the best economical, technical and ecological solutions for local construction problems. Given the high abundance of dune sand (DS) and the large quantities of plastic waste, plastic–mineral sand concrete can be a good alternative to the ordinary building materials available on the local market.

A replacement of sand by PAs is made by volume substitution. The plastic percentages laid down are 0%, 25%, 50% and 100%. Indeed, after a general experimental characterization of the studied composites, the investigation mainly concentrated on the study of the effect of the addition of plastic particles on the accelerated carbonation of river sand (RS) concrete and DS concrete, separately.

The density of the composites and consequently their compressive strength are slightly reduced; but their thermal insulation is significantly improved. Their structure seems to be homogeneous, the plastic grains are well distributed in the matrix and the adhesion “plastic–matrix” is good. At small plastic contents, the RS concrete is slightly better. As regards the carbonation results, the PAs significantly contribute to the improvement of the resistance of the composite against carbonation effect. It can be observed that increasing the proportion of plastic particles in sand concrete considerably decreases the thickness of the carbonated concrete.

The studies led on the behavior of plastic concrete, particularly in arid zones, are very limited. Moreover, for sand concrete, there are no similar studies. Therefore, the characterization of such materials is necessary. In addition of thermo-mechanical characterization, this work aims at studying the durability of the material, especially its resistance to carbonation. On the other hand, this work has a significant positive impact on both environment and economy, since it focuses on the recycling of industrial waste, and the valorization of DS, which is available in great quantities in south of Algeria.

Discusses the properties of concrete and the process of carbonation which can lead to corrosion and its ultimate destruction. Outlines the conditions which lead to carbonation, detailing design faults which facilitate the process, and suggests preventatives which can protect the surface. Examines the results of carbonation, the forming of distressed concrete and mentions tests which can be performed to check the health of the structure. Assesses the impact of additional factors leading to corrosion and offers advice on remedial actions.

This paper seeks to analyse 3D growing concrete structures taking into account the phenomenon of body accretion, necessary for the simulation of the construction sequence, and carbon dioxide attack.

A typical 3D segmental bridge made of precast concrete is studied through a fully coupled thermo‐hygro‐mechanical F.E. model. The durability of the bridge is evaluated and carbonation effects are considered. Creep, relaxation and shrinkage effects are included according to the theory developed in the 1970s by Bažant for concretes and geomaterials; the fluid phases are considered as a unique mixture which interacts with a solid phase. The porous material is modelled using n Maxwell elements in parallel (Maxwell‐chain model).

First, calibration analyses are developed to check the VISCO3D model capabilities for predicting carbonation phenomena within concrete and the full 3D structure is modelled to further assess the durability of the bridge under severe conditions of CO₂ attack.

The adopted numerical model accounts for the strong coupling mechanisms of CO₂ diffusion in the gas phase, moisture and heat transfer, CaCO₃ formation and the availability of Ca(OH)₂ in the pore solution due to its transport by water movement. Additionally, the phenomenon of a sequential construction is studied and numerically reproduced by a sequence of “births” for the 3D finite elements discretizing the bridge. The fully coupled model is here extended to 3D problems for accreting bodies (as segmental bridges) in order to gather the effects of multi‐dimensional attacks of carbon dioxide for such structures.

This paper aims to analyse the behaviour of dune sand mortars with the addition of ceramic waste. The objective of improving the performance of these modified mortars was evaluated in terms of accelerated carbonation performance.

The effect of these recycled materials was studied in an experimental programme through several tests. The carbonation depth was determined using a classical phenolphthalein test. The mass fractions of Ca(OH)₂ and CaCO₃ were calculated using thermogravimetric analysis, water absorption occurring through capillary action and open porosity, and the mechanical characteristics were measured after subjecting the materials to wetting–drying cycles.

The results show that using ceramic waste provides better performance in terms of water absorption by capillary action, open porosity and carbonation penetration.

This research is a study of the incorporation of ceramic waste up to 10 per cent in dune sand mortar. The choice of using ceramic waste to produce dune sand mortars has benefits from economic, environmental and technical points of view and offers a possibility for improving the durability of mortars.

The limitation of bridges’ operation can cause serious social, environmental and economic losses. Therefore, the monitoring and maintenance actions of these structures must be efficient and periodic, especially for bridges located in aggressive environments, such as urban-industrial centres, where the higher volume of carbon dioxide emissions favours carbonation induced corrosion. The purpose of this paper is to analyse the utility of including non-destructive testing (NDTs) to bridges assessment in that regions as a way of obtaining more in-depth information on the conditions of the material composing the structure.

First, the main bridges’ damages were detected by visual inspection. Then, based on the observations of bridges design, environment and main damages, an NDT programme was executed including surface hardness, ultrasonic pulse velocity test, pH indicator spraying, half-cell potential measurements and concrete resistivity tests.

It was observed that, for the studied cases, the carbonation did not present harmful depths, except for the structural elements where segregation and wear of the concrete were noticed. NDTs, associated with visual inspection, indicated the regions where corrective or preventive maintenance actions were actually needed, bringing greater security to the decision maker in regions where repairs are unnecessary or could be postponed.

This paper highlights the contribution of NDTs application in structures in urban-industrial regions where the main mechanism of deterioration is carbonation-induced corrosion, demonstrating the importance of these methods in the rational decision making of investments for maintenance.