Title:
Tests on Concrete Reinforced with Hybrid or Monolithic Steel and Polyvinyl Alcohol Fibers
Author(s):
Keun-Hyeok Yang
Publication:
Materials Journal
Volume:
108
Issue:
6
Appears on pages(s):
664-672
Keywords:
fiber-reinforced concrete; fiber-reinforcing index; hybridization; polyvinyl alcohol fiber; steel fiber; tensile resistance capacity.
DOI:
10.14359/51683470
Date:
11/1/2011
Abstract:
A total of 30 fiber-reinforced concrete (FRC) mixtures and a control fiberless concrete mixture were tested to examine the significance and limitation of hybrid or monolithic FRC with a fiber-volume fraction of less than 1%. The FRC specimens investigated were classified into three groups. The purpose of the first and second groups was to ascertain the effect of length and volume fraction of monolithic polyvinyl alcohol (PVA) fiber and steel (ST) fiber, respectively, on the workability and mechanical properties of concrete. The third group was designed to examine the hybridization of different lengths and types of fibers using PVA and ST fibers. Test results showed that the hybridization of PVA and ST fibers was slightly more effective in enhancing the tensile resistance capacity of concrete than the use of a monolithic ST fiber when the fiber-reinforcing index was greater than 2.5. In addition, hybridizations of 12 and 15 mm (0.468 and 0.585 in.) lengths for PVA fiber and 30 and 60 mm (1.17 and 2.34 in.) lengths for ST fiber were advantageous, achieving a better ductility of hybrid FRC compared with the use of only 15 mm (0.585 in.) length for PVA fiber and only 60 mm (2.34 in.) length for ST fiber. Overall, the hybridizations of different lengths and types using PVA and ST fibers resulted in a considerable synergistic effect in enhancing the tensile resistance capacity and energy absorption capacity of concrete while relieving the slump decrease of fresh concrete due to the addition of fibers.