Effect of steel fibers on the interfacial shear strength of flyash and GGBS based geopolymer concrete activated with water glass

Abstract

Concrete, a fundamental construction material, heavily relies on cement, manufacturing process of cement results in significant CO2 emissions, posing environmental concerns. Hence, exploring substitutes for cement becomes imperative to mitigate CO2 emissions. Geopolymer materials emerge as promising alternatives capable of entirely replacing Ordinary Portland Cement (OPC). However, these materials necessitate activators to initiate the polymerization reaction. While Na2SiO3 and NaOH are commonly utilized as activators, their cost-effectiveness is questionable. Moreover, when Ground Granulated Blast Furnace Slag (GGBS) reacts rapidly with these activators. To address these issues and streamline concrete production, “water glass” is employed as an activator, offering a solution to avoid rapid setting and economize the production process. In other hand the production of mass concrete structures, interfaces and joints critical points where cracks may develop. To ensure monolithic behavior, shear ties were advised at the interface in order to establish strong bond strength. However, the efficiency of construction could be decreased by adding more shear ties. The purpose of this study is to evaluate the interfacial shear strength of Geopolymer concrete (GPC), With the addition of different percentages of steel fibers 0.5, 1%,and 1.5%, with shear ties at the interface of push-off specimens. The findings reveal that it is viable to replace two shear ties with one 8 mm-2L shear tie and 1% crimped steel fibers of 30 mm length.