Certification and operation audit of segmental bridge launching gantries

The Maumee River Crossing Project is a large scale concrete bridge project. The contractor chose segmental construction which required the use of four different types of gantries. To assure a consistent design basis, all of the gantries were checked using the governing project engineering standards and project-specific loads. Due to the unique movement capabilities of these launching structures, each construction step from launch to final segment release was examined for each span, and span-specific work methods were developed. In some cases, gantry modifications were required to handle the project demands. In other cases, constraints posed by the supporting structures necessitated the use of structural supplements and customized operational procedures. A physical inspection of all gantries was performed to verify as-build conditions. In addition, quarterly operation audits were carried out to observe launch procedures and conformance of span-specific work methods.