The project is one of two under way today as part of a national campaign by Microsoft Corp. and the organization Feeding America, titled "Browser for the Better," to fight hunger in the United States.
In New York City's Time Warner Center, the Empire State Building is being constructed with cans of tuna.
Microsoft purchased 4,000 cans of chicken noodle soup and black beans from Trader Joe's for the construction of the replica bridge, Claycomb said by phone from the construction site this morning.
The soup cans, which have red labels, will comprise the bridge and the bean cans, whose labels are blue, will be the water beneath it, he said. "We're about halfway through," Claycomb said late this morning.
"We created the span and are doing the road connecting the spans now."
The bridge will be 7 feet tall, 12 feet long and 4 feet wide.
Claycomb, 29, and three other artists and friends started the project around 6:30 a.m. and plan to finish between 2 and 4 p.m. The bridge will be dismantled around 7 p.m. and the beans and soup will go to the San Francisco Food Bank.
Claycomb said he got involved in the project through a friend who works for Microsoft.
"I'm all for that good cause, of helping people with low incomes who are struggling getting meals," Claycomb said.
Peter Le Page, a product manager for of Microsoft's Internet Explorer team, said 17 million children who qualify for reduced-priced breakfasts and lunches during the school year are not receiving them over the summer.
Under the "Browser for the Better" campaign, Microsoft will donate $1.15 for each completed download of Internet Explorer 8 between today and Aug. 8. Internet Explorer 8 was launched in March.
Le Page said the $1.15 is the equivalent of eight meals through Feeding America's 206 food banks in the country.
Feeding America provides food assistance to 25 million low-income people each year, including 9 million children and 3 million seniors.