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Green building materials are an alternative to ordinary materialsoffering multiple environmental benefits. This study consists of an experimental investigation of a new design of gypsum plaster blocks. First, a mix design of gypsum plaster and water mixture was prepared. The optimal mix composition was determined according to the mechanical and physical properties, such as the water absorption, the temperature of hydration, the density, and the compressive strength of different gypsum plaster and water mixtures made by varying the water dosage. The second part of this investigation aims to study a new design of green blocks prepared from the optimal water and gypsum plaster mixture. The new blocks are perforated to lighten them and to reduce their thermal conductivity in order to make them moreinsulate. Experimental tests were conducted on the block prototype, such as the measurement of dimensional tolerances, compressive strength, density, flatness, water absorption, residual moisture, surface hardness, and thermal conductivity. Experimental test results show that the new blocks have very low density, and their compressive strength is sufficient for wall construction. In addition, the manufacturing process of the new blocks is very easy and very fast. Finally, the obtained physical and mechanical properties of the new gypsum plaster blocks give it the opportunity to be used for interior walls for building constructions.

Self-compacting concrete (SCC), which appeared in the 1980s in Japan, is a concrete that differs from others by its high fluidity. The constituents of SCC can be quite different from those of ordinary concretes. They can differ both in their proportions and in their choice. Given the method of installation of SCCs, particular attention is paid to the study of their physical and mechanical characteristics. In this context, experimental tests were conducted to assess the effect of high temperatures on the behavior of SCC. For this purpose, a SCC and ordinary concrete (OC) were tested at temperatures of 20, 150, 300, 450, and 600 ∘C. Prismatic specimens of dimensions 100 × 100 × 400 mm3, cylindrical specimens of dimensions 160 × 320 mm, and parallelepiped specimens of dimensions 270 × 270 × 40 mm3 were prepared for physical (thermal conductivity) and mechanical (compressive strength, elastic modulus, flexural strength, and ultrasonic pulse velocity) tests. The results showed an increase in the compressive strength for SCC between 150 and 300 ∘C following an additional hydration of the cementitious matrix. The residual flexural strength of the concretes decreases progressively with the increase in temperature. This reduction is about 90% from 450 ∘C to 600 ∘C. The results also showed that the thermal conductivity of concrete decreases as the temperature increases and can reach a value of 1.2 W/mK for the heating temperature of 600 ∘C.

Literature has shown positive results to using waste plastic as an alternative source for PMBs where considerable interest in using waste High-density polyethylene (HDPE) has been highlighted on improving rutting resistance. Most importantly, using a waste polymer for an application has benefits (i.e., maintenance, environmental) by improving the durability and quality of our roads and by avoiding polymers from landfill or incineration. This research uses the Multiple Stress Creep Recovery (MSCR) test to assess the performance of a binder modified with waste HDPE polymer. The outcomes of this research highlights that a HDPE content of 2–4% shows a substantial increase in rutting resistance and an improvement in elastic recovery. The elastic recovery reported does improve from previous research results however it does underperform in comparison with the Styrene butadiene styrene (SBS) polymer counterpart. Furthermore, it can be indicated by the aging index that a HDPE content of greater than 4% can be detrimental to the aging effects leading to fatigue cracking. It is recommended that a combination of both waste HDPE and an elastomeric polymer such as crumb rubber is to be used in future test work to improve the elastic recovery and address the effects of fatigue cracking.