This paper presents an experimental study on the influence of metal fibers on the mechanical behaviour of mortar with glass sand. Four mortar mixtures with glass filler and metals fibers are manufactured. The specimens were prepared with three percentages of glass sand (0%, 5%, 10%) and 1%, 2% by vol of steel fibers. The Air-Entraining Agent (A-E-A) dosages at the ratios of 0.08% of cement weight were used. The mechanical tests were carried out on the specimens such as the compressive strength, the tensile strength and the porosity. The results showed that the tensile and bending properties of all different mixtures with fibers are significantly higher compared to the reference mortars. A remarkable decrease has been observed in water, density and compressive strength of mortar with chemical admixture. Moreover, the using 1% volume fraction of steel fibers and 10% glass sand, flexural strength of mortar was completely improved.

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Recycling and recovery of waste are now considered as a solution for the future to protect the environment. The marble processing workshops on the other hand, generate a large amount of waste in the form of powder and small parts. Due to these facts, the aim of this study is to valorize marble waste in the form of powder and crushed aggregates (sand) as additions in cementitious matrix building materials. The characterization of the materials used to formulate mortars based on natural dune sand with marble powder and mortars based on mixed sand (dunes sand and crushed sand) and marble powder was measure. In this sense, several series have been studied, varying the addition rate of the marble powder in order to reduce the porosity of the cement matrix, using crushed marble sand to increase the granular cohesion and using of a reducing water admixture (MEDAPLAST SP40) for more performance mortars. Very appreciable results were observed for a dosage of 15% of marble powder and for the combination of 15% of marble powder with 20% of crushed marble sand. This research recommends recycling 35% of marble waste in the cement matrix that contribute effectively to the preservation of the environment.

Demand for aggregates is growing considerably in line with the development of construction in Algeria. To overcome it, it will be necessary to ensure a rational exploitation of the aggregates available to the country by aevaluation of the existingresources. According to the statistics, the glass wastes accounted for 7% of the world’s solid wastes. The glass wastes can be used in concrete production in two forms: replacing part of aggregate or using as supplementary cementmaterial to replace cement. Using glass wastes to produce recycled aggregates for the production of new concrete reduces the consumption of natural resources as well as landfills.This work consists in formulating a micro-concrete with a substitution of 5 to 25% by weight of crushed calcareous aggregates of fraction 3/8 by glass aggregates of the same fraction 3/8. The incorporation of glass wastes as an aggregate in the micro-concrete plays a role of skeleton and improves its compressive mechanical strength.The compressive strength is considerably improved by substitution of crushed calcareous aggregates by recycled glass aggregates. The optimum has been reached for a value of around 46 MPa for a substitution of 10% of crushed limestone aggregates. The substitution of 10% crushed gravel by crushed glass allows improving the strength of more than 27%.The results obtained provedthat waste glass can be used as an aggregate for producing micro-concrete with a relatively high strength which will not deteriorate with time.

High performance concrete (HPC) has several advantages in building construction that cannot be achieved using conventional concrete in terms of strength durability, resistance to chemical attack, and workability of high performance concrete are high. The introduction of fillers and additives contributed to the improvement of high-performance concrete (HPC), other parameters also influence the performance of these HPCs, coarse aggregate fraction is known to strongly influence both fresh and hardened concrete’s properties. Consequently, selection of both content and particle size distribution for (HPC) mixture is an important issue regarding the predicted performance of concrete. For to make concrete more improvement , the porosity of the granular skeleton as well as the rheology of our HPC, 3/8 fraction of rolled gravel with smooth and rounded surfaces was introduced, in substitution for the crushed gravel of the same fraction , by testing various combinations of fractions 3/8 of rolled gravel and fraction 8/15 of crushed gravel in the present study, and based on previous results obtained the combinations 35,40 and 45% fraction 3/8 of rolled gravel and 65 , 60 and 55% fraction 8/15 of crushed gravel (binary granular system) respectively, gives a minimal porosity . Super plasticizer and four percentages of pozzolan were experimented. Compressive strength function of coarse aggregate was determined at 7, 14 and 28 days. Results have revealed that the mixtures with modified granule size distribution system ,1.5% of superplasticizer and 5% by weight of pozzolan allow an improvement in the compressive strength of 35.1% relative to the control concrete.