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This paper aims to express a mathematical model that predicts the effect of mineral additives on the physical–mechanical properties of high-performance sand concrete (HPSC), using SAS's JMP7 statistical analysis software.

A mixture design modeling approach is applied to sand concrete (SC) for optimizing mixtures without being obliged to do a lot of experiments, where the cement is partially replaced with two mineral additives silica fume (SF) and blast furnace slag (BFS) in proportions as high as 20% of the mass. A total of 15 mixtures of sand concrete is prepared in the laboratory using this analytical technique in combinations with binary and ternary systems to estimate the workability and the compressive strength (CS) of sand concrete at 7 and 28 days.

The results obtained showed that the use of derived models based on the experimental design approach greatly assisted in understanding the interactions between the various parameters of the studied mixtures; the mathematical models present excellent correlation coefficients (R² = 0.96 for CS7 days, R² = 0.93 for CS28 days and R² = 0.95 for slump) for all studied responses. Moreover, it was also found that the inclusion of additives (SF and BFS) in binary mixture SC12 and ternary mixtures SC8 leads to a significant improvement in mechanical strength compared to reference sand concrete SC15. These results give the possibility to obtain a formulation of HPSC.

This paper shows the possibility of manufacturing high-performance sand-concrete with good compressive strength; the developed mathematical model by using SAS's JMP7 statistical analysis software allowed us to reach a strength compression value of about 60 MPa, in 28 days, by replacing 10% of the cement weight with silica fume. Furthermore, with partial replacement of the cement weight (15%) with two additions such as silica fume (10%) and blast furnace slag (5%), a 58 MPa of compressive strength can be achieved, without overlooking the fact that this can be a key economic and environmental alternative.

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.

This study is part of the valorization of local materials and the reuse of industrial waste in construction. This study aims to improve the physical-mechanical properties of sand concrete. This work is a continuation of previous studies conducted on sand concrete, the purpose of which is to introduce industrial waste into this material. For this purpose, a glass waste in powder form is added.

This study is focused on the effect of adding glass powder (GP) whose mass percentage varies from 0 to 40% with an interval of 10% to target the right composition that ensures the best compromise between the characteristics studied.

The results found show that the workability and density of the studied concretes decreased with increasing GP dosage. Indeed, the optimal addition which constitutes the best compromise between the studied properties is 10% of GP. Improvements of up to about 9% in the case of flexural strength and about 18% in the case of compressive strength. The thermal conductivity has been reduced by 12.74%, the thermal diffusivity which characterizes the notion of thermal inertia has been reduced by about 4% and the specific heat mass has been reduced by 7.80%. Also, the shrinkage has been reduced by about 20%. The microstructure of the studied composite shows a good homogeneity between the aggregates. Finally, the addition of GP to sand concrete gives very encouraging results.

The interest of this study is in two parts. The first one is the exploitation of local materials: dune sand, river sand and limestone filler to meet the growing demand for construction materials. And the second one is the reuse of glass waste, in the form of powder (GP), to solve the environmental problem. All this participates in the improvement of the physical-mechanical properties of sand concrete and the extent of its response to the development of an economical structural concrete.

Optimised concrete components are often of complex geometries, which are difficult and costly to cast using traditional formworks. This paper aims to propose an innovative formwork system for optimised concrete casting, which is eco-friendly, recyclable and economical.

In the proposed formwork system, ice is used as mould pattern to create desired geometry for concrete member, then sand mould is fabricated based on the ice pattern. A mix design and a mixing procedure for the proposed sand mould are developed, and compression tests are also performed to ensure sufficient strength of the sand mould. Furthermore, surface preparation of the sand mould is investigated for easy demoulding and for achieving good concrete surface quality. Additionally, recyclability of the proposed sand mould is tested.

The proposed mix design and mixing procedure can provide sufficient strength for sand mould in concrete casting. The finished components exhibit smooth surfaces and match designed geometries, and the proposed sand mould can be fully recycled with satisfactory strength.

To the best of the authors’ knowledge, this is the first study that combines ice pattern and sand mould to create recyclable formwork system for concrete casting. The new techniques developed in this research has great potential to be applied in the fabrication of large-scale concrete structures with complex geometries.

The purpose of this research is to evaluate construction and industrial waste materials in concrete using different additives.

The experimental study investigated the effect of waste foundry sand (WFS), waste glass (GW) as partial substituent to natural sand and addition of waste glass fibers (GFs) and silica fume (SF) in natural/construction waste aggregate concrete on mechanical properties, durability and microstructure using.

The results reveal significant strength enhancement on using two admixtures, the maximum increase in compressive strength was obtained on using 20% WFS and 0.75% GF for both natural (75% increment) and construction waste (72% increment) coarse aggregates. Using three admixtures simultaneously, the maximum enhancement in compressive strength was found for (WFS(20%) + GW(10%) + GF(0.75%)) for both natural aggregates (122% increment) and construction waste (114% increment) coarse aggregates as compared to control mix. The 28 days split tensile and flexural strength of natural/construction waste aggregate concrete improve with age appreciably for optimal contents of single, two or three admixtures and the maximum tensile and flexural strength increment was 135 and 97% for mix (WFS(20%) + GW(10%) + GF(0.75%)) with natural aggregates as compared to control mix. The microstructural analysis results indicate improved microstructure upon partial substitution of sand with WFS, GW and SF along with addition of waste GFs.

The use of construction and industrial waste as a substituent to natural aggregate/sand will provide far reaching benefits for the green construction and the environment at large.

The purpose of this paper is to implement the mathematical models to predict concretes physico-mechanical characteristics made with binary and ternary sands using a mixture design method. It is a new technique that optimizes mixtures without being obliged to do a lot of experiments. The goal is to find the law governing the responses depending on mixture composition and capable of taking into account the effect of each parameter separately and in interaction between several parameters on the characteristics studied.

Mixture design method was used for optimizing concretes characteristics and studying the effects of river sand (RS), dune sand (DS) and crushed sand (CS) in combinations of binary system and ternary on workability, the compressive and flexural strengths of concretes at 7 and 28 days. A total of 21 mixtures of concrete were prepared for this investigation. The modeling was carried out by using JMP7 statistical software.

Mixture design method made it possible to obtain, with good precision, the statistical models and the prediction curves of studied responses. The models have relatively good correlation coefficients (R² = 0.70) for all studied responses. The use of binary and ternary mixtures sands improves the workability and their mechanical strengths. The obtained results proved that concrete, based on binary mixture C15, presents the maximum compressive strength (MCS) on 28 day with an improvement of around 20%, compared to reference concrete (C21). For ternary mixtures, MCS on 28 day was obtained for the mixture C10 with an improvement of around 15% compared to C21. Increase in compressive strength during the progress of hydration reactions was accompanied by an increase in the flexural strength, but in different proportions.

The partial incorporation of DS (= 40%) in the concrete formulation can provide a solution for some work in the southern regions of country. In addition, the CS is an interesting alternative source for replacing 60% of RS. The concrete formulation based on local materials is really capable of solving the economic and technical problems encountered in the building field, as well as environmental problems. Local resources therefore constitute an economic, technological and environmental alternative.

Waste foundry sand (WFS) is a by-product of the metal casting industries and is used for land filling purposes. Disposing of waste creates problems to environment and increases disposal values. To reduce environmental pollutions and solving disposal problems, several authors in worldwide are carried out research work by partial and complete replacing of natural sand with WFS in concrete mixtures. It is found that WFS can be used for production of structural grade concrete. The mechanical characteristics and flexural properties of RC beams has been reviewed in this paper. From this literature review, it has been noticed that there are improvements in concrete strength properties with WFS.

The results of various properties of concrete have been discussed in this review articles such as compressive strength, split tensile strength, flexural strength, modulus of elasticity, SEM micro-structures and flexural strength properties of RC beams.

From the literature review, it is found that there is gap of research on flexural behavior of reinforced concrete beam with WFS.

By using WFS effectively, the environmental pollutions and dumping of waste can be reduced. WFS can be successfully used in structural concrete members.

This paper presents the effects of replacing fine aggregate (FA) with waste foundry sand (WFS) in natural aggregate and construction waste aggregate concrete specimens without and with superplasticizer (SP), silica fume (SF) and fiber (F) to solve the disposal problems of various wastes along with saving the environment. This study aims to investigate the effect of construction waste, WFS along with additives on the stress-strain behavior and development of compressive strength with age.

The various concrete specimen were prepared in mix proportion of 1: 2: 4 (cement (C): sand: coarse aggregate). The water-cement ratio of 0.5 (decreased by 10% for samples containing SP) to grading 1: 2: 4 under air-dry condition was adopted in the preparation of concrete specimens. The compressive strength of various concrete specimen were noticed for 3, 7 and 28 days by applying load through universal testing machine.

Upon adding construction and demolition waste aggregates, the compressive strength of concrete after 28 days was comparable to that of the control concrete specimen. An enhancement in the value of compressive strength is perceived when FA is replaced with WFS to the extent of 10%, 20% and 30%. If both construction and demolition waste aggregate and WFS replacing FA are used, the compressive strength increases. When FA is interchanged with WFS in natural aggregate or construction demolition waste aggregate concrete including usage of SF or F, the compressive strength improves significantly. Further, when construction and demolition waste aggregate and WFS replacing FA including SP are used, the compressive strength improves marginally compared to that of control specimen. The rate of strength development with age is observed to follow similar trend as in control concrete specimen. Therefore, construction and demolition waste and or WFS can be used effectively in concrete confirming an improvement in strength.

The utilization of these wastes in concrete will resolve the problem of their disposal and save the environment.

This study aimed to investigate the suitability and cost-benefit of using copper tailings as partial replacement of sand in concrete production. The study was motivated by the accumulation and non-use of copper tailings in dams among them tailing dam 25 also known as TD 25 in Kitwe city of the Copperbelt province in Zambia that take up approximately 111 hectares of unused land.

Laboratory experimental approach of concrete production based on water/cement ratios of 0.3 and 0.5 was used because this was an exploratory study designed to establish the primary performance of concrete. In total, 30 concrete cubes were cast based on the two water-cement ratios. In total, 0% to 30% partial sand replacement with copper tailings was used in both mixes with the 0% copper tailings replacement being the control mix and reference point. Other concrete tests included workability, density, compressive strength and element composition analysis.

Results revealed that copper tailings from TD 25 were suitable for partial replacement of sand in concrete. Thirty per cent of sand replacement with copper tailings was established as the maximum replacement amount to produce optimum compressive strength values from both mixes. The drier mix of 0.3 water-cement ratios produced higher compressive strength results of 23 MPa at 28 days of concrete curing with 2.34% as optimum concrete cost reduction.

The research results provide the cost-benefit analysis and savings that can be attained from using cheaper copper tailings based concrete. The study further provided the quantity of land available for development arising from absorption of copper tailings as a sustainable construction material. The local authority now has statistics and numerical values that it can use to absorb copper tailings as a concrete raw material.

The study provides guidance on optimum concrete grade produced and cost reduction details of copper tailing-based concrete to support for local authorities in suitable land wand waste management using real data.

To contribute to the identification of the parameters influencing the behavior of textile-reinforced concrete (TRC), the purpose of this paper is to investigate the flexural behavior of TRC-based plates under four-point bending notably designed in the context of sustainable development and the substitution of mortar components with natural and abundant materials.

An extensive experimental campaign was focused about two main parameters. The first one emphases the textile reinforcements, such as the number of layers, the nature and the textile mesh size. In the second step, the composition of the mortar matrix was explored through the use of dune sand as a substitute of the river one.

Test results in terms of load-displacement response and failure patterns were highlighted, discussed and confronted to literature ones. As key findings, an increase of the load-bearing capacity and ductility, comparable to the use of an industrially produced second textile layer was recorded with the use of dune sand in the mortar mix design. The designed ecofriendly samples with economic concerns denote the significance of obtained outcomes in this research study.

The novelty of the present work was to valorize the use of natural dune sand to design new TRC samples to respond to the environmental and economical requirements. The obtained values provide an improved textiles–matrix interface performance compared to classical TRC samples issued from the literature.