Bond-Stress Distribution of GFRP-Reinforced Concrete Beams Containing Seawater

Abstract

Many regions are experiencing freshwater shortages, which is projected to worsen in the coming years. The concrete industry is one of the largest consumers of water worldwide, limiting water available for agriculture and human consumption. Many affected areas have access to ample supplies of seawater, presenting an attractive alternative for concrete if certain issues can be addressed. The use of fiber-reinforced polymer (FRP) reinforcement rather than steel eliminates corrosion concerns associated with the high chloride content of seawater. Six beam anchorage specimens reinforced with spiral glass FRP (GFRP) bars were tested with embedment lengths ranging from 300 to 500 mm and cast using either potable water or artificial seawater. The bond stress, normal stress, and slip distributions along the bars are examined in detail, and a method for calibrating analytical bond–slip formulations is proposed. The results suggest that the short-term structural performance of seawater concrete is similar to that of concrete made with potable water, and that a relatively high friction stress can delay bond failure of spiral GFRP bars after the formation of longitudinal splitting cracks.