CONSTRUCTION STRESSES IN THE WORLD’S FIRST PRECAST NETWORK ARCH BRIDGE

摘要

This paper reports some of the major findings from the instrumentation of the West 7th Street Bridge in Ft Worth, Texas. This innovative bridge, completed in 2013 as a replacement for a century-old bridge, consists of 12 prestressed, precast network arches. The arches were instrumented with 224 vibrating wire gages that were embedded in the arches prior to concrete placement. The gages were monitored during post-tensioning, handling, and transportation operations as well as deck construction. The instrumentation provided valuable data on the stresses induced in the arches, which were used to ensure a safe environment throughout construction. The measurements also provided a means for evaluating the accuracy of assumptions that were made during design. The results obtained from this study provide a unique insight into the behavior of concrete arches built by an accelerated construction method.