Caesars Bay Plaza Cathodic Protection Design
LOCATION: Brooklyn, NY
GENERAL CONTRACTOR: Simpson and Brown, Inc.
CLIENT: Saltru Joint Venture
Caesars Bay Plaza is comprised of three separate pile-supported structures over the water with cast-in place girders supporting precast floor panels with a topping slab. It is believed that the buildings were built during the late 1950’s or early 1960’s. The plaza is located near the mouth of the Hudson River and is directly exposed to a marine environment. Over the years the structure has undergone multiple repair events due to the severe exposure. As part of an extensive foundation repair project conducted during 2015 to 2016, VCS was engaged to design an impressed current cathodic protection system and perform installation quality control and commissioning testing.
VCS conducted a corrosion condition assessment in 2012 to determine the reinforcing pattern, concrete quality, and corrosion condition of the girders for the three different structures. VCS’s findings were coupled with petrographic and chloride testing conducted previously by COWI. The data demonstrated that while many girders had visible corrosion distress; the entire structure was contaminated with high levels of chloride at the reinforcing level, so a global corrosion mitigation solution was warranted. It was determined that the best option to extend the life of the structure for at least 30 years was to replace and encapsulate the steel foundation piles and install an impressed current cathodic protection system using Ebonex® discrete tubular ceramic anodes in the girders.
Project Results and Conclusions:
A cathodic protection system was designed to protect the girder reinforcing steel for each building, using a similar strategy. Overall, the ICCP system was comprised of four (4) rectifier cabinets, fifty (50) independently controlled zones, 6500 Ebonex 18mm x 150mm anodes, and 100 embedded reference electrodes. Upon commissioning, the system is operating at 4.0 VDC or less with all zones providing >100 mV polarization.