Stress block parameters for steel fiber reinforced reactive powder concrete

Abstract

In this paper, an experimental investigation of six steel fiber reinforced reactive powder concrete (SF-RPC) columns was carried out deriving the appropriate design parameters of flexural induced columns with very high strength of concrete. Tested specimens have 200 mm square cross sections. Three of Six specimens have rebars with 400 MPa yield strength and another three specimens have no rebars. The SF-RPC mix contains 2% of 0.2 mm diameter by 13 mm long straight steel fibers improving compressive strength and tensile strength of RPC. Columns were induced to the flexural load by moment arm located at the end of columns with 10,000 kN UTM. From the experimental data on the axial load, moment and strains along the longitudinal direction of columns, we could aware of the stress block of SF-RPC would be the shape of triangle which needs new values for using ACI stress block parameter. Existing data of stress block parameter were investigated and regression analysis was carried out for evaluation of stress block parameter α1and β1 of SF-RPC.