Instrumentation and manufacture of a smart composite bridge for short-span applications

A smart composite bridge is described that features an all-composite design and an integral sensor network. This short-span structure is nine meters in length and is designed for an AASHTO H2O highway load rating. The prototype bridge, the first full-composite bridge in Missouri, was installed on the University of Missouri-Rolla campus as a field laboratory for smart structures courses and a demonstration of composite technology. It was designed, analyzed, and manufactured as a cooperative product development among university, industry, and government partners. It has a modular construction based on a pultruded 76-mm-square composite tube. The cross section of the overall structural element is an I-beam formed by seven layers of bonded tubes. The top and bottom layers are carbon/vinyl-ester tubes for strength and the other layers are glass/vinyl-ester tubes for economy. Extrinsic Fabry-Perot interferometric fiber-optic sensors were embedded throughout to measure temperature, flexure strain, and shear strain. Also, radio-frequency identification tags were co-located with sensors to aid in determining load placement during field tests. This paper gives an overview of the project emphasizing the smart instrumentation. In particular, the installation of the integral sensors, the plan for the sensor network, and preliminary strain results for vehicle loading are discussed.