Herbert Bonner Bridge Span#145 & Pier#144
On April 14, 2021, Span #145 and Piers #144/145 of the Herbert Bonner Bridge in Outer Banks, North Carolina, suddenly collapsed. The collapse left the northern portion of the Span precariously supported by a portion of Pier #144.
Having worked with CDI on a previous bridge demolition project, PCL Civil Constructors, Inc. (PCL) of Tampa, FL, under their contract with the North Carolina Department of Transportation, contacted CDI to plan and perform emergency explosives operations to bring the remainder of the Span and Pier down to an elevation where PCL could safely perform debris removal from the site.
While CDI’s emergency-trained torchmen performed preparations for future placement of linear shaped charges to transversely segment the 4-girder span at two (2) locations, and drillers to drill the remaining Pier for explosives segmentation, CDI’s office worked with PCL, NCDOT, the Coast Guard, NC Fish and Wildlife, and other regulatory agencies to develop an emergency blasting plan that would satisfy each agency’s requirements. After completion of preparations, explosives and protective cover placement by CDI, the Coast Guard cleared the marine exclusion zone, PCL blocked traffic on the new bridge, and the explosives operation was successfully carried out as planned.
Conveyor belting and geotextile fabric at-source protection limited fly of concrete debris and copper sheathing form the shaped charges. There was no damage to the new bridge or fish-kill as a result of CDI’s explosives operation on May 27, 2021. Both bridge and water traffic were reopened within minutes after CDI provided an “all clear” returning the site back to PCL’s control.