Provided by: the SCDOT
The Ben Sawyer Bridge Rehabilitation Project has reached several milestones over the past few weeks. Concrete has been placed for the first of two deck pours on both the northern and southern approach spans. At the former Navy Base in North Charleston, crews have set the two trusses for the swing span bridge and lifted the control house into place.
Reaching these critical points in the schedule enables the project team to narrow the window for the seven day (168 hour) closure of Ben Sawyer Boulevard, including the closure of the Intracoastal Waterway. The 168 hour closure can be expected to occur between the dates of November 1, 2009, and January 31, 2010, but not to begin between December 15, 2009, and January 3, 2009.
This narrowed closure window assures motorists that the Ben Sawyer Bridge will not be impacted by construction activities during the Isle of Palms Bridge Run on October 3, 2009. The project remains on schedule for a May 2, 2010, contract completion date for the replacement of the existing bridge and the consequent demolition of the old bridge.
Background on the seven day (168 hour) closure: To minimize disruption of traffic during the rehabilitation of the Ben Sawyer Bridge, the South Carolina Department of Transportation (SCDOT) challenged designers and contractors to use the latest construction engineering to meet the bridge rehabilitation requirements while only completely closing the bridge for seven days, or 168 hours. PCL Civil Constructors, Inc. was awarded the project’s design and construction contract in the fall of 2008. Their winning plan includes the construction of the bridge’s swing span off site while building new northern and southern approaches adjacent to the existing bridge. All seven days (168 hours) will be used in a block to remove the old swing span, slide the old bridge east off of its foundations, slide new approach spans onto the existing foundations, and then jacking the new swing span into place. Because the clock will be ticking, careful planning and coordination is required to assure staff, equipment, and even the weather is right for the closure countdown to begin.