US 101 Deck Replacement at Alemany Circle

San Francisco, California

BEST PROJECT and PROJECT OF THE YEAR FINALIST

KEY PLAYERS

OWNER | LEAD DESIGN FIRM: California Dept. of Transportation (Caltrans)

GENERAL CONTRACTOR: Myers & Sons Construction

SUBCONTRACTOR: Silverado Contractors; Martinez Steel; Jeffco Painting


Taking advantage of reduced traffic volumes resulting from statewide pandemic-related closures, the project team and Caltrans partnered to fast-forward this complex deck replacement on a Bay Area artery that typically handles nearly a quarter-million vehicles each day. Originally planned to unfold over several weeks during the summer, the project was instead begun three months earlier and compressed into a 10-day window.

highway construction

Photo courtesy Myers & Sons Construction

The accelerated schedule came with challenges. Along with rapidly incorporating COVID-19 safeguards to ensure a safe, productive jobsite, the team faced disrupted supply chains and manufacturing cutbacks that necessitated nationwide sourcing of critical materials. When the original steel rebar manufacturer was unable to meet preshipment cutting requirements, a new subcontractor was enlisted for the task. In just two weeks, the replacement firm precisely cut and delivered approximately 725,000 lb of rebar, keeping the overall project on schedule.

highway construction

Photo courtesy Myers & Sons Construction

To make the most of the limited time available, the team adopted a system of concurrent work phases. Operations worked in close succession to one another, progressing the length of the bridge in a train-like method of continuous construction. Aiding the effort was an innovative Type 3 concrete mix that could be placed quickly and set to strength within hours.

One challenge that remained constant was the project’s technical complexity. Limited deck widths, an elevated construction zone and lack of immediate laydown and work areas hindered accessibility for large equipment required for major infrastructure makeovers. The tightly hemmed, elevated structure required the concrete paver to be disassembled, reconfigured and then reassembled while telescoping cranes and concrete pumps were staged directly below.

highway construction

Photo courtesy Myers & Sons Construction

The fast-paced work and on-the-fly innovations were completed without compromising project quality or worker safety. Restaging work helped optimize social distancing without disrupting the time-sensitive workflow.  A strategic S-curve configuration shifted motorists to the opposite deck. This approach lowered speeds through the project site and reduced the risk of accidents while providing continuous corridor flow-through.

The results surpassed even the most optimistic expectations, with the project being completed in just six days—40% faster than the target window—with no safety incidents or COVID-19 transmissions among the 350 workers in the field.