Empirical Relationships on Mechanical Properties of Class-F Fly Ash and GGBS Based Geopolymer Concrete

Abstract

Ordinary Portland Cement (OPC) is one of the important materials used in the development of the construction industry. Production of OPC consumes lot of raw materials, emits extreme quantity of carbon dioxide (CO2) into atmosphere and highly energy-intensive. Thus, to reduce the production of cement so many attempts are done and an alternative binder was found. The alternative to cement concrete is geopolymer concrete (GC) and it is produced by mixing industrial by-products (rich in aluminosilicate) with an alkaline solution. This paper explores the mechanical properties and a representative non-linear equation was proposed for the relationship between splitting tensile Vs compressive strengths and flexural Vs compressive strengths of fly ash-GGBS synthesized GC cured at ambient temperature for 28 days. This work also presents empirical formulae for predicting elastic modulus of fly ash-GGBS synthesized GC. Equations were proposed to determine the splitting tensile strength, flexural strength and elastic modulus based on the compressive strength of GC. The obtained results are clearly indicating that the predicted (from proposed equations) splitting tensile and flexural strength values are very close to the experimental values. It is established that the formulae found in various codes and literature generally predict the higher values of the elastic modulus than those obtained using the proposed equation.

Effect of ground granulated blast furnace slag and fly ash ratio and the curing conditions on the mechanical properties of geopolymer concrete

“…Bellum et al proposed the Equation ( 21) to predict MOE based on fly ash-GGBFS based GPC. 58 Figure 15 shows the proposed equation with the other relative equations.…”

“…Lee and Lee proposed the Equation () for the prediction of MOE of GPC, 17 and Nath and Sarker proposed the Equation () for the prediction of MOE of ambient‐cured low‐calcium fly ash blended GPC. Bellum et al proposed the Equation () to predict MOE based on fly ash‐GGBFS based GPC 58 . Figure 15 shows the proposed equation with the other relative equations. where E c are modulus of elasticity in MPa, ρ are the density of the concrete in kg/m 3 and f c are characteristic strength in MPa.…”

Sodium hydroxide effect on the mechanical properties of flyash‐slag based geopolymer concrete

“…Australian code for the reinforced concrete design presented the correlation Equation ), and the Indian code introduced Equation ) between the flexural strength and compressive strength 28,29 . Ahmed et al proposed Equation ) in the international journal of structural engineering and Bellum et al also proposed Equation ) between the correlation of flexural strength and compressive strength 27,30 . Figure 16 shows the proposed equation shows that the flexural strength is around 15–16% of the compressive strength of the same mix of GPC.…”

Mechanical Properties of Geopolymer Concrete Containing Low-Alkaline Activator

“…[23] 5300√𝑓𝑓′ 𝑐𝑐 0.45√𝑓𝑓′ 𝑐𝑐 Using fly ash and 16.1% GGBS, and 9.1% alkaline activator Thomas et al [24] 4400√𝑓𝑓′ 𝑐𝑐 1.08√𝑓𝑓′ 𝑐𝑐 Using fly ash, 25.5% GGBS and 10.2% alkaline activator Albitar [25] 0.6√𝑓𝑓′ 𝑐𝑐 0.75√𝑓𝑓′ 𝑐𝑐 Using 18% fly ash and 6.7% alkaline activator Bellum et al [26,27] 0.77√𝑓𝑓′ 𝑐𝑐 0.98√𝑓𝑓′ 𝑐𝑐 Using 17% fly ash and 6.8% alkaline activator Cui et al [28] 874.5𝑓𝑓′𝑐𝑐 The geopolymer concrete stacking materials include fly ash, sodium silicate, sodium hydroxide, fine and coarse aggregate. The fly ash was taken from electric steam power plant (PLTU Lontar).…”