Author(s)

W. C. Liao

Abstract

Highly flowable strain hardening fiber reinforced concrete (HF-SHFRC) combines the excellent workability of self-consolidating concrete (SCC) in the fresh state, with the strain-hardening and multiple cracking characteristics of high performance fiber reinforced cementitious composites (HPFRCC) in their hardened state. This paper presents six HF-SHFRC mix designs, with compressive strengths ranging from 35 to 66 MPa. The results of two tensile tests, direct tensile test (dog-bone shaped specimen) and long prismatic tensile test with continuous reinforcement, are also carried out in this paper. All the mixtures show quite satisfactory in flowability and tensile properties, including strain-hardening and enhanced strain capacity due to the presence of the reinforcing steel strand. Keywords: strain hardening, SCC, HPFRCC, multiple cracking. 1 Introduction Highly flowable strain hardening fiber reinforced concrete (HF-SHFRC) combine the self-consolidating property of self-consolidating concrete (SCC) in their fresh state, with the strain-hardening and multiple cracking characteristics of high performance fiber reinforced cement composites (HPFRCC) in their hardened state. SCC has a high flowability and a moderate viscosity, and has no blocking by the reinforcement during flow. With proper use of superplasticizer (SP) and viscosity modifying agents (VMA), SCC can achieve higher flowability and higher slump without segregation, and also maintain better slump retention, thus making concrete more durable due to its lower water/cementitious ratio, and reducing sulfate attack and salt penetration.

Keywords

strain hardening, SCC, HPFRCC, multiple cracking.