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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.

The purpose of this study is to know the influence of palm oil fuel ash and metakaolin on the strength of concrete and crack resistance of reinforced concrete beam. An ordinary portland cement has been used in the concretes production where it is an important material to be considered due to its nature that reacts with every substance present. During the cement production, a significant amount of carbon dioxide is emitted from the clinker in rotary kiln and lot of energy is required in the production processes. Such an event can be prevented by replacing the part of cement with metakaolin (MK) and palm oil fuel ash (POFA). Aside from being a cementitious alternative, the materials can also contribute to a greener environment and more sustainable building, as POFA is available in Malaysia and may be used to substitute cement and minimize pollution.

This study assesses the effect of MK and POFA on the concrete in terms of compressive strength and cracks pattern of the reinforced concrete beam based on the relevant previous studies.

From this study, the compressive strength of concrete containing MK and POFA was higher than the control mix with the percentage of improvement in the range of 0.8%–78.2% for MK and 0.5%–14%, respectively. The optimum content of MK and POFA is between the range of 10% and 15% and 10% and 20%, respectively, to achieve high strength of concrete. Other than that, the inclusion of MK to the concrete mix improves the strength of reinforced concrete beams and reduces cracks on the surface of reinforced concrete beams, whereas the inclusion of POFA to the concrete mix increases the cracks on reinforced concrete beams. The cracks appeared within the flexure zone of every beam containing the MK and POFA.

It was found that the fineness of MK and POFA has a significant influence on the mechanical properties of concrete.

This study aims to characterize the behavior of blended concrete, including metakaolin (MK) and quarry dust (QD), as supplementary cementing materials. The study focuses on evaluating the effects of these materials on the fresh and hardened properties of concrete.

MK, a pozzolanic material, and QD, a fine aggregate by-product, are potentially sustainable alternatives for enhancing concrete performance and reducing environmental impact. The addition of different percentages of MK enhances the pozzolanic reaction, resulting in improved strength development. Furthermore, the optimum dosage of MK, mixed with QD, and mechanical properties like compressive, flexural and split tensile strength of concrete were evaluated to investigate the synergetic effect of MK and quarry dust for M20-grade concrete.

The results reveal the influence of metakaolin and QD on the overall performance of blended concrete. Cost analysis showed that the optimum mix can reduce the 7%–8% overall cost of the materials for M20-grade concrete. Energy analysis showed that the optimum mix can reduce 7%–8% energy consumption.

The effective utilization is determined with the help of the analytical hierarchy process method to find an optimal solution among the selected criteria. According to the AHP analysis, the optimum content of MK and quarry dust is 12% and 16%, respectively, performing best among all other trial mixes.

Three-dimensional (3D) printing technology allows geometric complexity and customization with a significant reduction in the structural environmental impact. Nevertheless, it poses a serious threat to the environment when organic binders are used. Binder jet printing of alkali-activated geopolymer precursor can represent a successful and environmental-friendly alternative.

The present work reports about the successful 3D printing of metakaolin-based alkali-activated concrete, with dimensional integrity and valuable mechanical behavior.

The geometric behavior was studied as a function of alkali activator flow rate, and the minimum geometric deviation with complete saturation was recorded at 103 mg/s. The printed specimen is characterized by a modulus of rupture as high as 4.4 MPa at 135 mg/s.

The 3D printed geopolymer-based concrete can be potentially used in a wide range of structural applications from construction to thermal insulation elements.

The analysis of the 3D geopolymer-based concrete printing system and material conducted in this paper is original.

The use of huge quantity of natural fine aggregate (NFA) and cement in civil construction work which have given rise to various ecological problems. The industrial waste like blast furnace slag (GGBFS), fly ash, metakaolin and silica fume can be partly used as a replacement for cement and manufactured sand obtained from crusher and partly used as fine aggregate. The purpose of this paper is to predict the shear strength of concrete using artificial neural network (ANN) for concrete made by using different pozzolans and partly replacing NFA by manufactured sand (MS) which can reduce the time and experimental cost.

In this work, MATLAB software model is developed using neural network toolbox to predict the shear strength of concrete made by using pozzolanic materials and partly replacing NFA by manufactured sand (MS). Shear strength was experimentally calculated, and results obtained from experiment were used to develop the ANN model. A total of 131 results values were used to modeling formation, and from that 30% data record was used for testing purpose and 70% data record was used for training purpose. In total, 25 input materials properties were used to find the 28 days shear strength of concrete obtained from partly replacing cement with pozzolans and partly replacing NFA by manufactured sand (MS).

The results obtained from ANN model provide very strong accuracy to predict shear strength of concrete obtained from partly replacing cement with pozzolans and NFA by manufactured sand.

This research study is on determining shear strength of concrete using ANN. The use of this study is to predict the shear strength of concrete using ANN for concrete made by using different pozzolans and partly replacing NFA by manufactured sand (MS) which can reduce the time and experimental cost.

The consumption of supplementary cementitious materials (SCMs) has increased enormously in the construction industry. These SCMs are often waste materials or industrial by-products. This study aims to investigate the bond strength using reinforcing bars in Normal Strength Concrete (M20 grade) and High Strength Concrete (M40 grade), developed using SCMs and data was compared with concrete prepared with ordinary portland cement (OPC). The findings of the study will help in reducing the dependency on OPC and promote the utilization of waste materials in Construction.

In the present study, the bond behavior between the steel bars and the concrete was investigated in controlled, binary and quaternary concretes of M20 and M40 grades. Following the conventional procedures, samples were prepared and mechanical tests conducted (as per IS:2770–1 code for M20 and M40 grade concrete structures), which showed an improvement in the bond strength depending on the extent of overall calcium and silica content in these composite mixtures, and thus reflected the importance of vigilant utilization of used industrial waste in the OPC as a replacement without exceeding silica content beyond certain percentages for enhanced structural properties.

Experimental evaluation of bond behavior results showed a brittle nature for the controlled (OPC) concrete mixtures. While binary and quaternary concrete was able to resist the load-carrying capacity under large deformations and prevented the split cracking and disintegration of the concretes. Among different variations in the chemistry, for both M20 and M40 grades, the maximum bond strengths were observed for 10% Metakaolin + 10% Silica Fume + 30% Fly Ash + 50% OPC composition and this could be attributed to the fineness of the additives, better packing and enhanced calcium silicate hydrate (C-S-H).

Quaternary concrete may be a future option in place of OPC concrete. Very limited data is available related to the bond strength of quaternary concrete. Experimental analysis on quaternary concrete shows that its use in construction can reduce both construction cost and a burden on natural raw materials used to make OPC.

This paper presents an experimental research on the performance of high-strength selfcompacting concrete (SCC) with different mineral additives after exposure to high temperatures of up to 600°C. For this purpose, four SCC mixtures were studied: one reference and three mixtures where the Portland cement was replaced with mineral additive (fly ash, metakaolin and limestone) in certain proportions. After natural cooling in the furnace, compressive strength and static modulus of elasticity were determined and compared to results obtained from other studies and those provided in EN 1992-1-2 and EN 1994-1-2 for normal-vibrated concrete. Additionally, acoustic emission (AE) parameters during compression test of heated and unheated specimens were also obtained which showed good non-destructive tool for identifying exposure temperature of the concrete needed for the assessment of concrete structures after fire.

Traditional simulation research of geological and similar engineering models, such as landslides or other natural disaster scenarios, usually focuses on the change of stress and the state of the model before and after destruction. However, the transition of the inner change is usually invisible. To optimize and make models more intelligent, this paper aims to propose a perceptible design to detect the internal temperature change transformed by other energy versions like stress or torsion.

In this paper, micron diamond particles were embedded in 3D printed geopolymers as a potential thermal sensor material to detect the inner heat change. The authors use synthetic micron diamond powder to reinforced the anti-corrosion properties and thermal conductivity of geopolymer and apply this novel geopolymer slurry in the direct ink writing (DIW) technique.

As a result, the addition of micron diamond powder can greatly influence the rheology of geopolymer slurry and make the geopolymer slurry extrudable and suitable for DIW by reducing the slope of the viscosity of this inorganic colloid. The heat transfer coefficient of the micron diamond (15 Wt.%)/geopolymer was 50% higher than the pure geopolymer, which could be detected by the infrared thermal imager. Besides, the addition of diamond particles also increased the porous rates of geopolymer.

In conclusion, DIW slurry deposition of micron diamond-embedded geopolymer (MDG) composites could be used to manufacture the multi-functional geological model for thermal imaging and defect detection, which need the characteristic of lightweight, isolation, heat transfer and wave absorption.

The purpose of this paper is to develop an alternative new ternary geopolymer mortar (MKSP) to resolve a traditional mortar problem which exhibits several disadvantages, including poor strengths and surface microcracks and the CO₂ air pollution.

The MKSP ternary binder was produced using metakaolin (MK), slag (S), and palm oil fuel ash (POFA) activated with an alkaline mixture of sodium silicate (Na₂SiO₃) and 10 M NaOH in a mass ratio of 2.5. Seven different mix proportions of MK, slag, and POFA were used to fabricate MKSP mortars. The water-to-binder ratio was varied between 0.4 and 0.5. The mortars were heat cured for 2 h at 80°C and then aged in air. Flexural stress and strain, mortars flow and compressive strength were tested. Furthermore, the mortars were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses.

The results showed that the sample MKSP6, which contained 40 percent MK, 40 percent slag, and 20 percent POFA, exhibited high compressive strength (52 MPa) without any cracks and flexural strength (6.9 MPa) at 28 days after being cured for 2 h at 80°C; however, the MKSP7 mortar with optimal strength of 55 MPa showed some surface cracks . Further, the results of the XRD, SEM, and FTIR analyses indicated that the MKSP mortars primarily consisted of a crystalline (Si+Al) phase (70 percent) and a smaller amorphous (Si+Ca) phase (30 percent).

The MKSP ternary geopolymer mix has three limitations as an importance of heat curing for development early strength, POFA content less than 20 percent to gain high normal strength and delaying the sitting time by controlling the slag content or the alkali activator type.

The use of geopolymer materials binder in a real building is limited and it still under research, Thus, the first model of real applied geopolymer cement in 2008 was the E-Crete model that formed by Zeobond company Australia to take the technology of geopolymer concrete to reality. Zeobond Pty Ltd was founded by Professor Jannie S.J. van (van Deventer et al., 2013), it was used to product precast concrete for the building structure. The second model was PYRAMENT model in 2002 by American cement manufacturer Lone Star Industries which was produced from the development carried out on inorganic alumino-silicate polymers called geopolymer (Palomo et al., 1999). In 2013 the third model was Queensland’s University GCI building with three suspended floors made from structural geopolymer concrete containing slag/fly ash-based geopolymer (Pathak, 2016). In Australia, 2014, the newly completed Brisbane West Wellcamp airport becomes the greenest airport in the world. Cement-free geopolymer concrete was used to save more than 6,600 tons of carbon emissions in the construction of the airport. Therefore, the next century will see cement companies developing alternative binders that are more environmentally friendly from a sustainable development point of view.

Production of new geopolymer binder of mortar as alternative to traditional cement binder with high early and normal strength from low cost waste materials, less potential of cracking, less energy consumption need and low carbon dioxide emission.

The purpose of this paper is to study the rapid prototyping of porcelain products by using layer‐wise slurry deposition (LSD), in order to reduce the time to market of new or customized porcelain products or artworks.

The properties such as phase composition, microstructure, shrinkage, density, and mechanical strength, of laser sintered (LS) and biscuit fired (BF) samples, before and after post sintering in a furnace, were studied and compared with each other.

The laser sintered sample was comparable with the biscuit fired sample in porosity, but had just half the mechanical strength of the latter due to the layer‐wise fabrication process. The feasibility of rapid prototyping of porcelain products was validated by the successful fabrication of some porcelain samples, which showed that the relatively low mechanical strength of the laser sintered sample was still high enough for the following handling processes, such as surface glazing and glost firing.

The paper demonstrates the possibility of rapid prototyping of porcelain components and the models produced by using LSD process.