Massman constructed the $100M replacement bridge for the existing Broadway Bridge, carrying US Highway 70, in downtown Little Rock, Arkansas for the Arkansas Highway and Transportation Department. The new bridge is a double basket network tied arch, constructed on the same alignment as the existing bridge, supported by three bents over the Arkansas River. To minimize disruption to the travelling public, Massman executed an innovative plan to install the new bridge substructure underneath the existing bridge while it was under traffic; demolish the old bridge and complete construction of the new bridge in only 180 days. To meet this contract deadline, Massman installed the three bent main span foundations prior to closing the corridor of the existing bridge. This work consisted of constructing 24 each 8-foot 6-inch diameter drilled shafts with 9-foot diameter permanent casings. The shafts were drilled 65 feet into the rock on the floor of the Arkansas River. The project also included 26,000 square feet of retaining walls with 30,000 cubic yards of fill material. The structure contains 25,000 cubic yards of concrete and 13.5 million pounds of structural steel. Prior to the 180 day closure, 2 tied arches were assembled downstream of the bridge on falsework mounted on barges. Once assembled, the arches were floated into position in the river and set into their location.
Click below for a project video.