Effect of carbonation on the mechanical and durability properties of sandstone modified self-compacting concrete

Abstract

Sandstone is one of the most used dimensional stone in the construction industry. Rajasthan is producing More than 90% of sandstone from all over India. Eastern Rajasthan is one of the dominant areas where sandstone waste was obtained and used in this study. This stone waste was produced during the shaping of sandstone and due to very fine particle size, this waste was named as sandstone slurry (SS). Excessive open dumping of stone waste creates environmental pollution through air and water, which also need to be addressed. This study aims to utilise sandstone waste in the concrete sector as an alternative building material. In this research work, Pozzolana Portland Cement (PPC) was partially replaced by SS at a percentage of 0, 10, 20 and 30. Rheological properties were tested to determine the flowability and viscosity of concrete mixes. To evaluate the effect of carbonation concrete specimens were carbonated. Compressive, splitting tensile strength and rapid chloride penetration test (RCPT) was conducted on the carbonated sample (CS) as well as a non-carbonated sample (NCS). The impact of CO2 concentrations was also determined by performing accelerated carbonation test. The test results revealed that carbonation enhances the compressive and splitting tensile strength properties of concrete by reducing pore structures. The depth of chloride penetration of CS is less as compared to NCS. However, accelerated carbonation displayed an increased depth of carbonation.