Project Overview
Wayne County is and has been going through a major program to upgrade and / or replace aging existing bridges to meet bridge safety requirements. NTH has worked as a subconsultant to Michael Baker International to evaluate subsurface conditions at the locations of the referenced bridges. For the Merriman Road and Goddard Road bridges, Wayne County’s requirement was to demolish and replace the existing bridges with new structures and new substructures. For the 5 Mile Road bridge, the County requested that the existing abutment and substructures be rehabilitated and reused and only the superstructure and bridge deck elements replaced.
Project Scope
For each of these projects, prior to moving into final design, a well planned and executed geotechnical investigation was required to determine the prevailing ground conditions and evaluate requirements for replacement bridge elements and approach pavement sections. Throughout each of these projects, NTH staff worked closely with bridge design staff at Michael Baker to provide recommendations that would be consistent with their design methodologies.
For each of the structures, NTH also obtained sediment samples for purposes of laboratory testing to classify the gradation properties of each for purposes of evaluation scour protection requirements. Further, NTH also conducted limited environmental testing at each location to sample the existing structures for asbestos and lead paint for purposes of remediation and demolition disposal.
Client Benefit
As a result of our significant project experience within Wayne County, NTH was able to identify the anticipated ground conditions in advance of drilling to be able to plan the geotechnical investigations with sufficient accuracy that the originally planned drilling footages were close to the conditions that actually existed. Further, based on our MDOT bridge experience, NTH staff was very familiar with the application of computer software to evaluate lateral pile and pile group capacities required by Michael Baker for foundation design purposes.