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The study aimed to explore the effects of mineral admixtures – especially limestone filler (LF), brick powder (BP) and ceramic powder (CP) – on the performance of self-compacting sand concrete (SCSC). It studies their effect on mechanical properties and mass loss when exposed to acidic solutions (H2SO4 5% and HCl 5%) over periods of 28, 90 and 180 days. The study seeks to develop SCSC technology by taking advantage of locally available sand resources.

Using an experimental design, the study explores different formulation parameters, including the use of silty sand (AS) and dune sand (DS) in fixed proportions, where AS constitutes 70% and DS 30% of the total sand content. The superplasticizer ratio (SP) and water-to-binder ratio (W/B) are constant with varying amounts of mineral additives. The study immerses SCSC samples in acidic solutions (5% H₂SO₄ and 5% HCl) for 28, 90, and 180 days to evaluate mass loss and mechanical properties. This endeavor to advance such concrete technology is motivated by the desire to incorporate sand concrete into the realm of self-compacting concrete technology while also harnessing the advantages of locally available sand resources, particularly dune sand, which is abundant in the southern regions of Algeria.

SCSC results with mineral additives showed enhanced resistance in both tensile and compression tests, indicating improved durability compared to the reference sample without additives. However, excessive proportions of BP (>60%) or CP led to exceptions in this trend An exception to this trend was observed when BP was added in proportions exceeding 60% or when CP, indicating potential limitations in some additive formulations. Overall, the research provides valuable insights into improving the performance and durability of SCSC through the strategic incorporation of mineral admixtures, contributing to advances in self-compacting concrete technology.

1 – Valorization of local materials and recycling of waste: DS, LF, BP and CP, which are available in great quantities in the south of Algeria; 2 – Combination, at the same time, of alluvial sand and dune sand as aggregate and LF, BP and CP as filler. 3 – Application of the design of experiments method methodology for the optimization of these elements of the new sand concrete studied. The new building material elaborated present indeed a technical, economic and environmental interest.

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.