May completion set for 580/680 Interchange in Pleasanton, California
The north I-680 to east I-580 connector is in the foreground, with the south I-680 to east I-580 connector curving in the background. The south-to-east connector opened on February 1, 2002, much to the delight of commuters.


The new Hopyard Boulevard off-ramp runs under the southeast and northeast connectors. This ramp is in a temporary alignment while the permanent tie-in to the eastbound I-580 is being constructed.
FCI North's first contract with Caltrans will wrap up this May. Awarded in June 1989, the $52 million 580/680 interchange is located in Pleasanton, California. The project included constructing five new bridges, with the longest at 4,400 feet. Three bridge widenings were also included.

This complex project was designed to help relieve the congestion for more than 275,000 motorists a day, so traffic control was a major consideration during construction. FCI North crews installed 45 miles of concrete piling, 53,000 cubic yards of concrete, and 70,000 tons of asphalt concrete.

In May 2000, the first structure was opened to the public. It was the Big Canyon Creek on-ramp to northbound 680. The last and largest flyover opened to the public on February 1, 2002. This 706-foot-long structure included an extremely difficult section that crossed over I-580 and BART. Special requirements from BART included designing falsework to withstand lateral loads caused by a seismic event. Mike Eckert designed the falsework to withstand 13 percent of the total dead load in the horizontal direction. The Caltrans standard in 2 percent.

Since a significant portion of the flyover was constructed over I-580 and I-680 and the BART tracks, much of the work had to be done at night and in short time frames. Only four-hour work windows were allowed over the interstates, and only two hours over BART. Falsework crews worked several months of nights under freeway closures erecting and removing falsework.

The final phase of construction is to complete the widening of I-680 southbound to allow for a new on-ramp from the city of Dublin to southbound I-680. The deck closure pours have been completed, and paving work should be done by the end of April. The final traffic switches should occur in April and May of this year. Congratulations to the FCI North team on the successful completion of this challenging project.


The flyover spanning both interstates was opened to the public February 1, 2002. Here, the flyover crosses over the new southbound I-680 ramp from Dublin.
 
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