Effect of surface treatment of apricot shell on the performance of lightweight bio-concrete

The effects of different surface treatment of apricot shell (AS) on the performance of concrete were investigated. Five surface treatments were used to treat the AS, including soaking AS with cement solution (CS), waterproof agent (WP), sodium silicate (SS), white latex (WL), and coating AS with wood oil (WO). The results showed that the WP and CS treatments improved the physical properties, mechanical strength and resistance to magnesium sulfate of apricot shell bio-concrete (ASC). The WP treatment increased the density and decreased the porosity and water absorption of concrete. The compressive strength, splitting tensile strength, flexural strength, modulus of elasticity of the WP treated bioconcrete improved 9.3%, 16.3%, 15.1% and 19.2%, respectively, compared to the untreated mixture. The SS and WL treatments had a negligible influence on the performance of ASC. However, the WO treatment significantly increased the porosity, which resulted in a reduction in mechanical properties and resistance to magnesium sulfate. The WP and CS treatments enhanced the resistance to magnesium sulfate of ASC. It is concluded that the AS treated with waterproof agent is an effective method to enhance both the mechanical properties and durability of the developed lightweight bio-concrete. (C) 2019 Elsevier Ltd. All rights reserved.