Title: High-Srength Fiber Reinforced Concrete Utilizing Closely Spaced Reinforcing Bars
Author(s): B. Aarup
Publication: Symposium Paper
Appears on pages(s): 1-8
Keywords: fiber reinforced concretes; high-strength; precast; structural applications
CRC ( Compact Reinforced Composite) is the designation for a special type of fiber reinforced concrete with high strength (150-400 Mpa) and closely spaced reinforcing bars. The dense matrix-with water/powder ratios of typically 0.16-provide a good bond to fibers and reinforcing bars, and the large content of steel fibers provide the ductility necessary for utilizing reinforcement effectively. The steel fiber content is typically 2-6% by volume and the content of reinforcing steel is 2-10% by volume. The improved durability of the matrix- due to a high micro silica content-makes it possible to use a concrete cover to the reinforcement of only 10mm in aggressive environments, improving the effectiveness of the reinforcement. The CRC concept was developed in 1986 and aimed specifically for use in structures such as beams, columns and joints, but most of the applications so far have been in the security industry, for corrosion protection and in heavily loaded floors. However, in the last few years CRC has also been applied in structures. One of these applications, production of 40,000 drain covers for a tunnel as a replacement for cast-iron covers, is described as an example of a project where the properties o high performance fiber reinforced concrete were utilized.