Service Life Extension Program for Dry Docks 10 and 11

Northrop Grumman's shipbuilding and repair facility in Newport News, Virginia (formerly known as Newport News Shipbuilding, NNS) is home to adjacent Dry Dock 10 and 11. These graving docks were designed and built under a high profile and accelerated construction schedule as "temporary" cellular sheet pile structures in the days immediately before the United States' involvement in World War II. At the time, the design of this type of structure using sheet pile cells was without precedent. Today, these "temporary" structures still serve as mission-critical facilities, since all scheduled refueling operations for the U.S. Navy's nuclear-powered Nimitz-class carrier fleet occur in Dry Dock 11. Northrop Grumman initiated a comprehensive Service Life Extension Program (SLEP) for these dry docks in an effort to extend their service lives another twenty-five years in order to accommodate the projected refueling schedule for the remainder of the carrier fleet. The project involved an in-depth analysis and evaluation of both the existing sheet pile structures, the design of repairs for these structures, the comprehensive implementation of the repair details, and the specification of on-going inspection and monitoring efforts which will help to enable the continued use of the facilities. Since cellular steel sheet pile structures comprise much of our country's aging waterfront infrastructure; the analysis techniques, design methods, construction practices, and on-going monitoring efforts which have been developed and put into practice by Northrop Grumman at the Newport News facility are applicable to a wide-range of waterfront facilities.