Structural performance of hybrid fiber reinforced polymer–concrete bridge superstructure systems

A novel hybrid fiber reinforced polymer (FRP)–concrete structural system was applied to bridge superstructures. The hybrid FRP–concrete bridge superstructure systems are intended to have durable, structurally sound, and cost effective hybrid system that will take full advantage of the inherent and complementary properties of FRP materials and concrete. The proposed hybrid FRP–concrete system consists of trapezoidal FRP cell units surrounded by an FRP outer shell forming a bridge system. A thin layer of concrete was placed in the compression zone.

As a trial case, a prototype bridge superstructure was designed as a simply-supported single span one-lane bridge with a span length of 18.3 m. Performance of this superstructure was examined both experimentally and computationally. A test specimen, fabricated as a one-fourth scale model of the prototype bridge, was subjected to a series of loading tests: nondestructive tests (flexure, off-axis flexure, and negative flexure), and destructive tests (flexure and shear).

Results from both experimental and computational analysis confirmed that the proposed hybrid bridge superstructure system has an excellent performance from structural engineering point of view. Furthermore, it was shown that a detailed linear finite element analysis (FEA) could predict behavior of the test specimen under different service loading conditions.