Evaluation of Steel Fiber Reinforced Geopolymer Concrete Made of Recycled Materials

Abstract

In the last few decades, the geopolymer concrete presented an evolution in civil engineering field. The current study aims to produce a low cost steel fiber reinforced geopolymer concrete with an ecceptable tensile properties. The experimental program aims to investigate the tensile behaviour of geopolymer concrete reinforced with steel fiber and made of recycled materials. The primary ingredients of the steel fiber reinforced geopolymer concrete in this study were waste materials. The recycled steel fiber was extracted from tires and chopped into tiny fibers with an average length of 20 mm and an average diameter of 0.7 mm. The geopolymer concrete in this study consisted of coarse aggregate, which was crushed recycled concrete. Also, the fine aggregate was crushed waste glass. In addition to the compressive strength, tensile test procedures such as splitting tensile strength, double punch tensile strength, and flexural tensile strength were all investigated in this study. Recycled steel fiber was compared to a new hooked-end steel fiber and hybrid steel fiber (50% new + 50% recycled) with three different volumetric percentages of steel fiber (0.5%, 1.0%, and 1.5%). The new steel fiber geopolymer concrete mix with 1.5% of steel fiber showed the highest test results among other mixes, as the tensile strength was increased by nearly 50% in the case of the double punch test. This conduct could be explained as the new steel fiber having a uniform, straight shape with hooked ends, increasing the anchorage between the fly ash binder and the steel fiber. In addition, the recycled steel fiber was contained some rubber crumbs that could be another reason that negatively affected the tensile properties of the geopolymer concrete.

Behavior of Reinforced Geopolymer Concrete Beams under Repeated Load

“…The beams were subjected to a successive cycle of loading and unloading (repeated loading) (7). Through this type of loading, as shown in Figure 3.…”

“…Both ordinary concrete and geopolymer concrete are weak under tensile stresses and for this reason; the concrete in tension is neglected in many international codes and depends in totally on the strength of steel reinforcement to resist the tensile strength in structural members. While plain concrete tensile strength enhanced significantly by adding steel fibers to the concrete mix (7). The use of geopolymer cement can reduce carbon dioxide emissions by 44-64% compared to Portland cement (8).…”

The Post-fire Behavior of Lightweight Structural Concrete is Improved by Nano-SiO2 and Steel Fibers

“…Mohammadi and Bagheripour [7] studied the engineering properties of self-compressing lightweight concrete (SCLWC) after adding fibers to it and found that the compressive strength was improved by adding 1% fine steel fibers. Goaiz et al [8], Mohammed and Kadhim [9] showed that adding fiber increased compressive strength. A study by Varghese et al [10] showed that carbon fiber-reinforced concrete samples had better residual shear strength than others.…”

Effect of Varying Glass Powder Size on Performance of Cement Mortar: Microstructural and Compressive Strength Assessment at High Temperatures

“…The concrete industry, heavily reliant on non-renewable resources and CO2-intensive processes, presents a significant opportunity for sustainability through the exploration of alternative materials (1). Concrete, a primary construction material, typically contains 10-15% Portland cement (OPC), with the remainder being aggregates, water, and other additives.…”