Adewumi John Babafemi

Applied Voltage on Corrosion Mass Loss and Cracking Behavior of Steel-Reinforced SHCC and Mortar Specimens

AbstractThis study compares the durability, in terms of resistance to corrosion, of strain-hardening fiber-reinforced cement-based composite (SHCC) and the same matrix without fiber (mortar). The c...

Performance of strain hardening cement-based composite (SHCC) under various exposure conditions

Abstract The performance of strain hardening cement-based composite (SHCC) under various exposure conditions such as chloride-induced accelerated corrosion, capillary water absorption (CWA), electrical resistivity (ER), and freezing-thawing (CDF) tests is reported. SHCC was compared with two reference mortars; one is the same strength class as the SHCC (M1), and the other is a high strength class (M2). Both cracked and uncracked beam specimens were tested. Results from the investigation show that, in SHCC, the corrosion potential is a function of crack width. It is suggested that the half-cell corrosion potential measurement technique may not truly reflect the corrosion state of an embedded steel bar in SHCC. The result of the CDF test reveals that after 42 cycles of freeze-thaw attacks, SHCC performed better than M1 and M2.

Macro-Synthetic Fibre Reinforced Concrete: Creep and Creep Mechanisms

The creep of cracked macro-synthetic fibre reinforced concrete has been investigated in uniaxial tension at five stress levels (30, 40, 50, 60 and 70 %) of the residual uniaxial tensile strength under controlled temperature and relative humidity of 23 ± 1 °C and 65 ± 5 % respectively. Specimens were prepared and cracked before they were subjected to the various stress levels. One mix design has been used throughout the investigation and the fibre was used at a volume of 1 %. Test results of the investigation has revealed that while the creep response is a function of the applied stress level, significant creep has been recorded after 8 months even at lower stress levels. The mechanism responsible for the time-dependent crack opening of macro-synthetic fibre reinforced concrete was investigated through time-dependent fibre pull-out and fibre creep tests. The result of this investigation has shown that macro-synthetic fibre creep and the time-dependent fibre pull-out are mechanisms responsible for the creep of cracked macro-synthetic fibre reinforced concrete.