Preserving a Memorial: The Use of Impressed Current Cathodic Protection on a Historic Steel Frame Rotunda

摘要

The subject of this paper, a limestone rotunda located in Chicago IL is a testament to Veteran Members of a national fraternal organization. In 1923, as a tribute to their fallen soldiers, the organization began building a classical limestone rotunda with modern and seemingly durable construction materials of the time. This included the use of a steel frame at the entablature which support vast limestone panels of the 30 foot high colonnade. Through weathering and exposure, detailing and previous repairs, the embedded steel frame and anchorage caused corrosion related damage to the masonry. After a corrosion investigation and an assessment of the clients' requirements, Impressed Current Cathodic Protection was chosen as an optimal repair solution. This addressed corrosion activity, provided a cost saving, required a shorter construction duration than a traditional repair, and met the client's preservation goals. The structure had complex detailing which was not recorded in the original drawings. Notwithstanding, there were challenges in construction which the team overcame for the successful installation of the system. This paper addresses the progress of the project, the construction challenges, and the final installation.