Our investigation included visual observations, structural analyses, and a scour evaluation, completed in collaboration with a geotechnical subconsultant.
Scour had damaged the west granite fieldstone abutment and we recommended closing the bridge until this abutment could be repaired. Since the east abutment showed no signs of scour or damage and had a proven history of good performance, we designed a new ashlar-granite-clad concrete structure for the new west abutment and retained the existing east abutment. Our rehabilitation design also included refurbishing the riveted steel superstructure and replacing deteriorated wood decking.
SGH worked with the contractor to develop construction sequencing for lifting the superstructure in one piece off its existing abutments, placing it in the adjacent park during rehabilitation of the superstructure, and resetting the rehabilitated structure back on the new west abutment and existing east abutment.
The engineering and construction team successfully completed the project as a MassDOT-Highway Accelerated Bridge Program project, in cooperation with DCR.