In 2008, the Missouri Department of Transportation (MoDOT) embarked on an aggressive campaign to replace 554 structurally deficient and functionally obsolete bridges in a single design-build contract known as “Safe & Sound.” The objective was to rapidly reconstruct a significant portion of the bridge inventory with minimum disruption to the traveling public. MoDOT used this opportunity to deploy three HCB bridges to further add to its suite of solutions for Accelerated Bridge Construction (ABC). A Highways for LIFE (HfL) grant from the Federal Highway Administration was leveraged to address three different types of bridging solutions using Hillman Composite Beams (HCB®s), including B0439.
The first of the Safe & Sound HCB bridges to be constructed was B0439. Although the HCB itself can qualify as a prefabricated bridge system, MoDOT wanted to investigate the viability of the HCB system using Stay-in-Place (SIP) precast concrete deck panels to eliminate the additional operation of deck forming. Further acceleration of the construction schedule was facilitated by pre-filling the HCB units in a staging yard prior to installation. Although this reduces the lightweight benefits of the HCB, the contractor was still able to put two filled beams on one truck, cutting the freight cost in half from conventional beams and the beams remaining one-third the weight of comparable concrete box beams.
Bridge B0439 carries Missouri Route 76 over Beaver Creek in Douglas County. This three-span bridge also represents an example of a multi-span HCB bridge made continuous for live loads. Continuity was achieved through cast-in-place diaphragms at the piers and negative moment reinforcing steel in the deck slab, similar to what would be used with prestressed concrete beams.
The end result was a rapidly deployed bridge that required a smaller crane for erection while providing a corrosion-resistant bridge with reduced long-term maintenance costs for MODOT.
HCB Piece Weight:
Owner: Missouri Department of Transportation (MoDOT)
Contractor: KTU Contractors
Completion date: November 2010
Project Sheet: Click here for downloadable PDF version
“The technical expertise that HCB Inc. provided was fantastic. They answered any questions we had and worked with us to develop some techniques for erecting them. Using HCBs reduced trucking substantially. We were able to move four beams per truckload. If we had used conventional beams, we would have had to use significantly more trucks. Located in a marine environment, Knickerbocker Bridge was a great application for HCBs because it will withstand corrosion better than steel or concrete.”