4.1 Introduction

Polymeric composites are advanced engineering materials with the combination of high-strength, high-stiffness fibers (e.g., E-glass, carbon, and aramid) and low-cost, light-weight, environmentally resistant matrices (e.g., polyester, vinylester, and epoxy resins). The use of fiber-reinforced polymer or plastic (FRP) composite materials can be traced back to the 1940s in the military and defense industry, particularly in aerospace and naval applications. Because of their excellent properties (e.g., lightweight, noncorrosive, nonmagnetic, and nonconductive), composites can meet the high performance requirements of space exploration and air travel, and for this reason, composites were broadly used in the aerospace industry during the 1960s and 1970s (Bakis et al. 2002). From the 1950s, composites have been increasingly used in civil engineering for semi-permanent structures and rehabilitation of old buildings. A concise review on FRP composites for construction applications in civil engineering is given by Bakis et al. (2002).

Structures made of FRP composites have been shown to provide efficient and economical applications in bridges and piers, retaining walls, airport facilities, storage structures exposed to salts and chemicals, and others. In addition to light-weight, noncorrosive, nonmagnetic, and nonconductive properties, FRP composites exhibit excellent energy absorption characteristics - suitable for seismic response - high strength, fatigue life, and durability; competitive costs based on load capacity per unit weight; and ease of handling, transportation, and installation. FRP materials offer the inherent ability to alleviate or eliminate the following four...