Survey and investigation of performance of superstructure of long span bridges in China

Abstract

With the rapid development of China’s economy in the past three decades, requirements for construction of infrastructure for transportation have been enhanced and a great many long-span bridges have been built. Internationally, it can be boasted that China is one of the countries with the most long-span bridges. However, inadequate performance in long span bridges is often observed in field investigations, such as, excessive deflection in the mid-span, cracking of the concrete, cable corrosion in cable-stayed bridges, suspender cable corrosion in suspension bridges, and the corrosion of reinforced steel in the concrete resulting in the scaling and spalling of the concrete cover. This arouses the concern for the safety, serviceability, durability, service life, life cycle cost of maintenance and rehabilitation of long span bridges. A survey was made on the working condition of long span bridges in China. The causes resulting in deterioration of long span bridges are examined and measures for prolonging the service life of long span bridges in view of design, construction and maintenance are proposed.