Comprehensive experimental investigation of the mechanical properties and performance enhancement of polyvinyl alcohol fiber-reinforced cement mortar

Abstract

This research experimentally analyses the fabrication, testing, and development of cement mortar incorporating Polyvinyl Alcohol (PVA) fiber at concentrations of 1%, 2%, and 3% by volume of the total cementitious matrix. PVA fiber geometry with a length of 8 mm and a diameter of 40 µm, specifically the RECS 15/8 mm type, was utilized due to its optimal balance between mechanical performance and workability. Mechanical tests, including three-point bending, were conducted to assess the load–deflection behavior, ultimate strength, and energy absorption capacity of the reinforced beams. The scope of this study encompasses tensile strength, elastic modulus in four-point bending with un-notched specimens, fracture energy in three-point bending with notched specimens, and compressive strength tests. The addition percentages of PVA fibers (1%, 2%, and 3%) were selected to investigate the effect of fiber concentration on mechanical properties systematically and to identify the optimal reinforcement level for enhancing performance. Tensile strength values exhibited a clear enhancement with increasing PVA fiber content, recording 1.96 MPa, 3.17 MPa, and 5.12 MPa for 1%, 2%, and 3% PVA fiber, respectively. The Elastic Modulus, determined through four-point bending with un-notched specimens, demonstrated a notable increase in stiffness, with values of 26.17 GPa, 53.63 GPa, and 67.7 GPa for 1%, 2%, and 3% PVA fiber, respectively. Three-point bending tests with notched specimens revealed improved energy absorption capabilities, as indicated by Fractured Energy values of 1.33 N.mm/mm², 2.98 N.mm/mm², and 3.91 N.mm/mm² for 1%, 2%, and 3% PVA fiber. Furthermore, compressive tests yielded increased strengths, with values of 46.8 MPa, 57.2 MPa, and 73.9 MPa for 1%, 2%, and 3% PVA fiber, respectively. The goal of this research is to explore and quantify the benefits of adding PVA Fibers to cement mortars, focusing on enhancing mechanical properties such as tensile strength, elastic modulus, fracture energy, and compressive strength. The findings are particularly beneficial for developing auxetic cementitious materials, offering applications in advanced structural components, earthquake-resistant structures, protective barriers, flexible pavements and runways, and innovative architectural designs. The results highlight the potential of PVA fibers to significantly enhance the performance and durability of construction materials, paving the way for advanced and resilient building components.