Variability of mechanical properties of basalt fiber reinforced polymer bars manufactured by wet-layup method

Abstract

Basalt fiber reinforced polymer (BFRP) bars were produced with basalt fiber that was made from igneous basalt rock. These bars were produced by adopting a new type of automated wet lay-up process for potential use as internal reinforcement of concrete. While the determination of mechanical properties of BFRP is an important first step, statistical investigation of the variability of mechanical properties is critical both for determining guaranteed properties and the quality control of production. The objective of this study was to determine the variability of mechanical properties of BFRP bars in order to verify the usefulness of the new process. Statistical analysis techniques were applied to investigate the variation and distribution of the data set obtained from tensile tests of BFRP bars. The results of Kolmogorov–Smirnov (K–S) tests revealed the data to be normally distributed meeting a confidence level of 99.875%. This would make it possible to determine the guaranteed properties based on the American Concrete Institute (ACI 440.1R) and the Canadian Standards Association (CSA S806) approaches. The study revealed that the BFRP bars manufactured by using the new automated wet-layup process had variation similar to that of FRP bars manufactured by other methods. However, this process has economic benefit relative to the traditional pultrusion method due its simplicity and cost effectiveness resulting from less stringent production controls.