OceanaGold Corporation was planning to expand the Haile Gold Mine, first opened in 1827, with a new 900-foot-deep open pit that was expected to have a 13-year lifespan.
M3 called on KCI to design a new bridge over U.S. 601 to carry the new haul road that connects the new site to the nearby 524-acre tailings storage facility. The structure was designed to carry the Caterpillar 785C off-highway mining truck that has a 10-foot diameter and a gross machine operating weight of 550,000 pounds.
Our team finalized the design of a 90-foot-long, 42-foot-wide bridge with a five-foot-wide pipe trough to carry slurry for the mining operations. Engineers used a 3D grillage analysis to determine load effects on the structure. The bridge sits on 72-foot-long modified bulb tees spaced five feet apart with a 15-inch-thick deck slab on top. A five-foot-tall bridge parapet ensures that bridge rails extend to the axel height of the design truck.
During the construction phase, KCI reviewed shop plans, provided plan clarifications, answered Requests for Information (RFIs), and provided milestone inspections, in addition to acceptance inspections of prestressed concrete beams prior to the beams leaving the precasting yard. Our team also performed temporary falsework and girder erection plans on behalf of the contractor during construction. At the close of construction, engineers performed the final inspection and created the punchlist on behalf of the owner and SCDOT.