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This study presents experimental results about the effect of incorporating waste rubber aggregates in combination with waste glass powder or silica sand powder obtained from dune natural sand, on the performances of cementitious mixtures. Rubber aggregates (RW) were used to replace crushed sand in concrete mixes with ratios of 10%, 20%, 40% and 60%, while glass powder (GP) and natural sand powder (SP) were used to replace 15% of the cement weight. Nine different forms of concrete with the separate wastes and with the combination of them were designed and prepared. The mixtures were characterized in the fresh and hardened states by means of workability, fresh density, compressive and tensile strengths, propagation of ultrasonic waves and deformability tests. The water/binder ratio and superplasticizer percentage of all mixtures were maintained constant. The results showed that the strength increased with the incorporation of glass powder and rubber aggregates, especially with 10% and 20% RW contents. In addition, the developed rubberized concrete with the incorporation of glass powder presented higher fresh density and deformability, compared to the cementitious rubberized mixtures without GP. Furthermore, the simultaneous incorporation of rubber waste and glass powder enhanced the concretes workability due to the low GP and RW water absorptions. Recently, researchers worldwide up the challenge to assess the usability of this industrial waste in cementitious materials, however, their performance has to be defined. The most recent studies related to the use of rubber aggregates and chips obtained from the used tires milling as a partial replacement of fine and coarse aggregates should be highlighted [9-24]. Blessen et al. [9] studied the properties of high strength rubberized concrete that contains scrap tire rubber. Crumb rubber was used to replace natural fine aggregate from 0% to 20% in multiples of 2.5%. It was observed a significant improvement on the abrasion resistance and water absorption properties, while mechanical and durability of high strength rubberized concrete were observed to be less than that of the control mix. Similarly, Ganjian et al. [10] tested the effect of replacing coarse aggregates by chipped tire and cement by powder tire crumb. Based on the results, they obtained a reduction in compressive strength about 10-23% and 20-40% for replacing natural aggregates and cement with chipped rubber, powder rubber respectively. In addition, Aslani et al. [11] practiced the replacement of

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Nowadays, the construction is one of the main European sectors responsible for the high levels of energy consumption and raw material extraction. Increasingly, the energy consumption from renewable sources and industrial waste reuse are the only ways to minimize these environmental and societal problems. Simultaneous incorporation of phase change materials and fly ash in the mortars increases the energy efficiency and decreases the waste materials landfilled. The development of mortars with phase change materials and fly ash incorporation contributes to a significant improvement of the building comfort parameters and the environmental quality. The phase change materials possess the capability to normalize the temperature flux inside the buildings, using the solar energy as resource. The main purposes of this study were the physical, mechanical, and thermal characterization of mortars with phase change materials and fly ash incorporation. It was concluded that the phase change materials and fly ash simultaneous incorporation leads to homogeneous and suitable mortars with increased thermal behavior compared with the phase change material addition alone.

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