In the mid 1990's the FHWA established a High Performance Concrete (HPC) program aimed at demonstrating the positive effects of utilizing HPC in bridges. Research on the benefits of using high performance concrete for bridges has shown a number of benefits. These include increased span capacities, or wider girder spacings (and hence a fewer number of girders); increased concrete compressive and...

In an external prestressing system, there is no strain compatibility between the cable and the concrete at every cross-section, the increment of cable strain must be evaluated by taking into account the whole structure, rather than performing the calculation at each section, independently. In this study, a method for the calculation of cable strain, which is based on the deformation compatibili...

Orbit correction is now routinely performed at the few-micron level in the Advanced Photon Source (APS) storage ring. Three diagnostics are presently in use to measure and control both AC and DC orbit motions: broad-band turn-by-turn rf beam position monitors (BPMs), narrow-band switched heterodyne receivers, and photoemission-style x-ray beam position monitors. Each type of diagnostic has its ...

The research described in this paper focuses on the application of modal strain techniques on a multi-girder bridge superstructure with the objectives of identifying the presence of damage and detecting false damage diagnosis for such structures. The case study is a one-third scale model of a slab-on-girder composite bridge superstructure, comprised of a steel-free concrete deck with FRP rebars...