Carbon Fiber CFRP Retrofit for Infrastructure: Bridge and Building Seismic Strengthening

Introduction

Carbon fiber reinforced polymer (CFRP) retrofit systems have transformed the way engineers approach infrastructure rehabilitation, particularly for seismic strengthening of bridges and buildings. Traditional strengthening methods — steel jacketing, concrete enlargement, or post-tensioning — add weight to structures that may already be load-limited, and they often require extended shutdowns that disrupt traffic and economic activity. CFRP retrofit eliminates these constraints: the material weighs approximately 1.6 g/cm³ compared to steel's 7.8 g/cm³, can be applied without heavy equipment, and cures to full strength within days rather than weeks.

For aging infrastructure worldwide, CFRP retrofit represents a cost-effective path to extending service life while meeting updated seismic design codes. The global CFRP retrofit market for infrastructure is projected to exceed $2.5 billion by 2030, driven by aging bridges in North America and Europe, rapid urbanization in Asia-Pacific, and increasingly stringent seismic performance standards. This article examines how CFRP retrofit systems are designed, specified, and installed for bridge and building seismic strengthening applications.