Development of a Green High-Performance Fiber-Reinforced Cementitious Composite Using Local Ingredients

Recent materials developed and applied for repairing, strengthening, and refining the performance of various structural elements are high-performance fiber-reinforced cement composites (HPFRCCs). These materials exhibit appropriate strain-hardening behavior when subjected to tensile loading. Currently, an apparent need is felt for these construction materials in all the world's countries. The fibers used in HPFRCCs are primarily polyvinyl alcohol (PVA), polyethylene (PE), and high-tenacity polypropylene (HTPP) fibers. Due to the high cost and unavailability of the mentioned fibers, it is not possible to make HPFRCC in many parts of the world. The aim of this study is to achieve HPFRCC constructed from locally accessible ingredients and substances with proper mechanical properties, specifically increasing the tensile strain capacity and being consistent with the environment. For this purpose, 18 mixtures were examined in such a way that the written mix designs included various cases of cement type (ordinary portland cement, limestone calcined clay cement), filler type (silica sand, limestone powder, and their mixture), amount (in two ratio percentages of 0.5 and 1 concerning binders), and cases of water to solid ingredient ratios (0.2, 0.25, 0.3, 0.35, 0.4). The applied fiber in this article was ordinary polypropylene fiber, and in order to investigate the mechanical behavior of the studied mix compositions, compressive strength, direct tensile strength, a three-point bending test, and a scanning electron microscope (SEM) were used. Also, to assess the sustainability of mix designs, material sustainability indicators (MSI) were approved from the perspective of embodied energy and carbon footprint. Finally, it is shown that using local ingredients and ordinary polypropylene fiber, a green composite with a tensile strain capacity of 3.7% is possible. Moreover, replacing ordinary portland cement (OPC) with limestone calcined clay cement (LC3) in mixtures will decrease the compressive strength on average by 20%, increase the tensile strain capacity by 54%, reduce the production of carbon dioxide gas by 34%, reduce energy consumption by 18%, and increase the price by 4%.