Big Rock Interchange
Little Rock, Arkansas
The project, located in West Little Rock, was the largest contract ever awarded by the Arkansas Highway and Transportation Department at the time of construction. Built by Weaver-Bailey Contractors-Manhattan Road & Bridge Company (joint venture), the Big Rock Interchange project included new mainline pavement, ramps, lighting, eleven (11) mechanically stabilized earth retaining walls, and five (5) bridge structures (excluding the superstructure of Bridge 07192 – 1839’ long). Upon commencement of the project, the Project Owner elected to add the superstructure of Bridge 07192 by change order, increasing the contract value by $10.5 million and additional time.
The entirety of all five (5) bridge substructures included aesthetic (form-lined) multi-faceted motifs of pine cones, along with coordinating painting schemes for the complete bridge and retaining walls. The retaining walls were designed with a pine tree (forest) motif. All symbolic of the official state tree (pine tree) recognized in 1939 for the state’s pine timber resources and reforestation efforts.
The bridge work included seven (7) restricted areas of work – each limiting accessibility for equipment staging, relocating of equipment based on traffic configurations, delivery of fabricated steel girders, and erection of steel girders. These restrictions also limited the availability of temporary lane configurations, namely to off-peak and weekend-only times. The project team managed the overall schedule with the steel fabrication and delivery schedules to ensure “just in time” relocation of hoisting and shoring equipment, and the delivery of the girders. By design, the steel girder span lengths required multiple field splices over traffic. The project team engineered temporary shoring towers to accommodate the staged erection.
During the course of construction, excavation for the I-430 South to I-630 East Ramp uncovered a large outcropping of rock embedded with quartz. The project owner decided to leave the rock formation, resulting in the project being renamed the “Big Rock Interchange.”
Work on the project commenced in January 2011 and was completed and dedicated in August 2015. The joint venture received the maximum permissible incentive for early completion.