Title: Influence of Fiber Orientation on Bridging Performance of Polyvinyl Alcohol Fiber-Reinforced Cementitious Composite
Author(s): Toshiyuki Kanakubo, Masaru Miyaguchi, and Kohei Asano
Publication: Materials Journal
Appears on pages(s): 131-141
Keywords: bridging law; casting direction; elliptic function; fiber orientation; fiber-reinforced cementitious composites; image analysis; orientation intensity; uniaxial tension test
Crack bridging performance of fibers strongly affects the tensile characteristics of fiber-reinforced cementitious composites (FRCCs) after first cracking. The fiber orientation distribution is likely to be affected by factors that include fresh-state properties, casting method, formwork geometry, and others. The objective of this study is to investigate the influence of the fiber orientation on the bridging performance in polyvinyl alcohol (PVA) FRCCs through a visualization simulation using a water glass solution and a calculation of the bridging law. The main parameter of the investigations in the present study is the casting direction. To evaluate the fiber orientation distribution quantitatively, an approximation methodology using an elliptic function is newly introduced. The bridging stress versus crack width relationship is calculated considering the elliptic distribution, the snubbing effect, and the fiber strength degradation. The calculated stress-crack width curves can express the uniaxial tension test results after first cracking well.