J.J. Curran Crane Company, Inc., of Detroit, recently completed setting approximately 13 precast concrete bridge beams for the new Beach-Garland Road bridge over the Flint River in Flint in a breathtaking two days with a Krupp KMK 8500, 500-ton hydraulic crane.
The existing bridge was completely replaced. Hardman Construction Inc., of Ludington, was the prime contractor for the approximately $2.2-million project. The project began in August 2006 and it was completed in June.
The beams were approximately 93 feet long and weighed approximately 80,000 pounds each. The crane had 115 feet of luffing jib and a 100-foot radius.
"We always have to overcome site problems. This is a large crane. We have to erect the jib on the ground and then raise it. Hardman was pretty good and they were able to give us good access to the site," Craig Lindsay, engineer for J.J. Curran Crane Company, said.
"Whenever you're lifting over water it's a challenge, especially when you're pushing that much weight out that far. The crane was approaching its capacity. But it went well."
"It was a difficult location for tearing out a bridge and rebuilding one. There were tight quarters, it was in downtown Flint and it was in the Flint River. There were a lot of obstructions in the river that we dealt with and there were the normal utility problems that delayed the project one month in the beginning," Bruce Lowing, president of Hardman Construction, said.
The new bridge is a 186-foot-long by 55-foot-7-inch-wide concrete box beam bridge with a three-lane asphalt road, concrete curbs, sidewalks, and gutters.
"The river in that part of town is in concrete flood walls. This was a two-span bridge, so there was a pier in the middle of the river and the bottom of the river was lined with broken concrete. So, we had to remove that. We installed a cofferdam in order to remove the existing pier and build a new pier. That was a challenge, because there weren't very good plans for the existing pier," Lowing said.
"There also weren't very good plans for the existing flood walls on both sides of the river, where the new abutments went. So, there were a lot of challenges in terms of getting the cofferdam in so that we could build the substructure for the bridge."
Lowing explained that sheetpiling was placed for the cofferdams after rock and debris at the bottom of the river was removed.
"We'd run into a new concrete structure and we'd break that out under water so that we could get the rest of the cofferdam in. Basically, we ended up putting in sheet pile cofferdams around all of the substructure (the pier and the two abutments). The abutments and pier sat on foundation piles. Then we poured the concrete," Lowing said.