Experimental Investigation on High Strength Concrete Columns Reinforced with B500

Abstract

Concrete is a common material in construction, but it is weak in tension, often destroyed with cracks due to plastic and drying shrinkage. It was possible to use the introduction of separate short fibers into concrete to counter and prevent the spread of cracks. High strength concrete (HSC) considered as an improved material which is used for bridges, offshore structures and high rise building. The addition of fiber to HSC enhances durability, reduces shrinkage, and decreases chemical attack deterioration. This research presents an experimental program to clear the effect of steel fiber content, stirrups ratio, longitudinal steel ratio and grade on behavior of high-strength fiber reinforced concrete (HSFRC) columns subjected to axial load. Six columns have been cast and tested with compressive strength of 1000kg/cm 2 and steel fiber content of 0, 20, 40kg/m 3 .This paper highlights the results to investigate variables on the gain of strength, cracking load, ultimate load, failure mode and ductility. The experimental investigation provided that increasing amount of longitudinal reinforcement tends to increasing in ultimate load by 5%, increasing in strain at yield load in steel with 23%, while in concrete the strain was decreased by 36%. The load capacity was higher when the steel type was changed from B500DWR to B500CWR.