GGBFS-Based Self-Compacting Geopolymer Concrete with Optimized Mix Parameters Established on Fresh, Mechanical, and Durability Characteristics

Abstract

The current study presents an investigation into the optimal content determination of the mix parameters in their acceptable ranges through fresh, mechanical, and durability characteristics in ground granulated blast furnace slag (GGBFS) based self-compacting geopolymer concrete (SCGC) cured under ambient temperature. Ordinary portland cement (OPC) based self-compacting concrete (SCC) was prepared as a control concrete. Both the M25 SCGC and SCC were characterized through fresh property tests satisfying the flowability, passing ability, and segregation resistance; mechanical tests by both nondestructive and destructive tests; and durability tests through water absorption, sorptivity, acid attack, sulfate attack; and rapid chloride permeability test (RCPT). The prime mix parameters considered in SCGC with their variation ranges were molar concentration of sodium hydroxide (10M, 12M, 14M, 16M), sodium silicate to hydroxide ratio (1.5, 2.0, 2.5, 3.0), superplasticizer (SP) dosage (5%, 6%, 7%, 8%), and percentage of extra water (EW) (15%, 18%, 21%, 24%). The results of SCGC were compared with the control SCC and discussed. The mix parameter optimal values derived from all the fresh and hardened concrete properties were a 12M concentration of sodium hydroxide, sodium silicate to hydroxide ratio of 2.5, SP dose of 7%, and EW percentage of 21%. SCGC thus prepared is stable, workable, and exhibits superior properties to OPC-based concrete to promote sustainable development. The current study estimates the optimal quantity of mix parameters, i.e., 12M NaOH, AAS ratio of 2.5, 7% SP, and 21% EW to produce ground granulated blast furnace slag (GGBFS)-based self-compacting geopolymer concrete (SCGC) cured under ambient temperature. The SCGC-optimized mix-parametric values are evaluated based on the mix materials whose physical and chemical properties are declared in the manuscript. The cementless concrete thus prepared is GGBFS based, which is an industrial byproduct, yielding sustainable concrete. Under ambient temperature, the SCGC can be cured, which is practically beneficial for the in situ construction work. The self-compacting capability of SCGC involves minimal energy in producing a dense, smooth concrete surface, reducing both the construction period and cost involvement. Being a stable workable concrete, its nonsegregation nature makes it homogeneous with minimal entrapped air. The reduced permeability nature renders it a larger insulating potential. Concerning OPC-based concrete, SCGC has larger mechanical and durability characteristics, making it a better choice. Thus, the SCGC has a huge potential in the global construction sector and is practically applicable.