KCI was selected to provide construction engineering and inspection services for the widening of I-275 from south of Floribraska Avenue to north of Yukon Street. The 4.1-mile-long project included widening of 26 bridge pairs into 13 connected bridges, with four structures also being widened to the outside. A grass and guardrail median was reconstructed to include 16,746 linear feet of median barrier wall, 21,905 square yards of concrete pavement, stabilization, base, 10,862 tons of asphalt pavement, and various drainage structure improvements including two jack and bore casings under the interstate. The bridge widenings involved 36-inch and 48-inch drilled shaft foundations, 24-inch pre-stressed concrete pilings, and 18-inch steel pilings, reinforced concrete sub and superstructure, and 36-inch and 48-inch pre-stressed Florida-I beams. In addition roadway lighting, signing, ITS and pavement markings were replaced.
The project crossed four major arterial roadways and several other minor city streets. This portion of I-275 lies just north of downtown Tampa and carries approximately 170,000 vehicles per day. Daytime lane closure restrictions were required on both the interstate and city streets. Bridge construction over the Hillsborough River, which is a natural habitat for manatees, required close environmental permit monitoring.