Book Description

This Design Study Report presents the investigations made for the replacement of the MacArthur Bridge and its approaches in the States of Iowa and Illinois for US Route 34. The study area included all roadway and structures from the Central Avenue Bridge over US-34 in Iowa to the Burlington Northern railroad bridge in Illinois. The replacement river structure is set 75 ft downstream from the centerline of the existing bridge to the centerline of proposed US 34. The project is divided into three sections for the study. These are the Iowa Approach up to the first land pier for the river bridge, the river bridge from the first land pier in Iowa to the abutment on the river side of the Henderson County Levee, and the Illinois Approach from the river bridge abutment to the Burlington Northern railroad overpass. The selection of a structural concept for the river bridge has little or no affect on the construction cost of roadway items, demolition and structures at the Burlington Interchange which will be $2,993,000. For the river crossing, four concepts for the channel span-- a truss, a tied arch, and cable-stayed girders in steel and concrete--were investigated. Multiple girders in steel and in prestressed concrete and post-tensioned concrete box girder approaches were evaluated in conjunction with the channel span schemes. Based on estimated construction costs, which out-weigh other considerations, it is recommended that a simple span through truss with multiple prestressed concrete approach spans be constructed for an expenditure of $30,039,000. As multiple steel girders are competitive with multiple prestressed concrete girders, for the approach spans, it is further recommended that an alternate design be prepared for that portion of the structure. The construction cost for the Illinois approach has a minor impact from the selection of a river bridge concept and for the recommended scheme would be $2,956,000.