In recent years, the massive production of industrial waste is becoming a big scourge for our ecology system and all humanity.
Cement paste and mortar made with Silica waste powder is a new type of green building materials, which is environmentally friendly and has various application prospects. The type of Silica waste used in this research possesses a high silica content (87%) and is highly crystalline with a mean particle size of 37.4 μm. Silica waste was used in cement paste and mortar as cement substitute which can only be used up to 10% replacement in weight. We study this new material in comparison with silica fume since they have some similarities in terms of chemical composition. The concrete produced were tested for compressive strength and durability properties such as UPV, Thermal Conductivity, water absorption, we also focused on the sample microstructure by doing SEM/EDS and XRD. Mortar shows good results for UPV ( ≥3660 m/s) with a compressive strength around 90 MPa for 28 days which shows good properties of mortar mixed with Silica waste. Slump flow was also measured to estimate the fresh properties of concrete containing silica waste. It shows a decrease in slump flow with an increase in silica waste proportion.
With a Specific gravity of 0.65, it’s classified as a very light material and is flowable on the top of water and hardly mixable with water. In combination with latex, silica waste due to its high water repellency is also used as a coating material in order to play a waterproofing role. The mix design used is the ratio (L/S) between the Latex, considered as liquid and silica waste considered as solid. The tests we have conducted on the coated simples are mainly Contact angle Test, Water spray test and coating layer microstructure study. The optimum ratios showing good contact angle results (≥ 90o) are mainly L/S=2.5, 3 and 3.5.
Nowadays, researchers from all around the world are trying to find a more efficient way to use that industrial waste, mainly in the field of concrete science. Now the main work is a strategy to maximize those new waste materials performance.

In recent years, the massive production of industrial waste is becoming a big scourge for our ecology system and all humanity.
Cement paste and mortar made with Silica waste powder is a new type of green building materials, which is environmentally friendly and has various application prospects. The type of Silica waste used in this research possesses a high silica content (87%) and is highly crystalline with a mean particle size of 37.4 μm. Silica waste was used in cement paste and mortar as cement substitute which can only be used up to 10% replacement in weight. We study this new material in comparison with silica fume since they have some similarities in terms of chemical composition. The concrete produced were tested for compressive strength and durability properties such as UPV, Thermal Conductivity, water absorption, we also focused on the sample microstructure by doing SEM/EDS and XRD. Mortar shows good results for UPV ( ≥3660 m/s) with a compressive strength around 90 MPa for 28 days which shows good properties of mortar mixed with Silica waste. Slump flow was also measured to estimate the fresh properties of concrete containing silica waste. It shows a decrease in slump flow with an increase in silica waste proportion.
With a Specific gravity of 0.65, it’s classified as a very light material and is flowable on the top of water and hardly mixable with water. In combination with latex, silica waste due to its high water repellency is also used as a coating material in order to play a waterproofing role. The mix design used is the ratio (L/S) between the Latex, considered as liquid and silica waste considered as solid. The tests we have conducted on the coated simples are mainly Contact angle Test, Water spray test and coating layer microstructure study. The optimum ratios showing good contact angle results (≥ 90o) are mainly L/S=2.5, 3 and 3.5.
Nowadays, researchers from all around the world are trying to find a more efficient way to use that industrial waste, mainly in the field of concrete science. Now the main work is a strategy to maximize those new waste materials performance.

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