Would you pay a higher price if it bought a lower cost? For contractors and specifiers, there is a big difference between price and cost. While price is but one element of cost, it is the initial, most visible and the easier of the two to understand. Focusing on price is not a preferred strategy in any business, especially where high-quality, reliable manufactured goods are concerned. Instead, for precast concrete products, the focus should be on the Total Cost of Ownership (TCO).
This project was showcased by the Federal Highway Administrator, Victor Mendez in July 2011, receiving national attention for the innovation it used to get the bridges built so quickly and safely, and for limiting major impacts on road users to off-peak hours.
The 93 Fast 14 Bridge Replacement, hosted by the Federal Highway Administration’s Highways for LIFE program, attracted highway officials from 26 states. These transportation leaders came to learn how to use customer service and safety-driven innovative techniques on their bridge construction projects.
The project team fabricated the bridges in segments off site, eliminating years of work in the roadway. The segments MassDOT used are called PBUs or Prefabricated Bridge Units. Each PBU is composed of a concrete deck with two steel beams underneath it. The PBUs were installed by crane and connected with a rapid-setting concrete, replacing at least one bridge each weekend. By replacing the bridges with bridge units that were fabricated off-site, MassDOT eliminated years of work in the roadway.
The bridges, built roughly sixty years ago, had reached the end of their service lives and were suffering from deterioration. The concrete of the bridge decks was in poor condition. The steel beams under the concrete decks were also in need of repair. MassDOT replaced the steel beams and concrete decks, which together make up the part of the bridge called the superstructure. The bridges’ piers and abutments, which make up the bridges’ substructures, were in good condition. MassDOT repaired the fourteen bridge substructures and revised them to fit the replacement superstructures.
This historic project replaced fourteen bridges in Medford over the course of just ten weekends between June and August, 2011. MassDOT used several innovations, a detailed traffic management plan and a comprehensive communications plan to complete the bridge work safely, efficiently, economically, and in a manner that caused the least possible construction-related impacts and congestion. The project was completed on-budget and ahead of schedule, replacing all fourteen bridges in less than a year. Using conventional methods, this project would have taken at least four years, and during those four years drivers would have had to endure long-term lane closure.
Project Team
GEI Engineering – Design and Management
J. F White – Construction
W.L. French – Demolition and Transportation