Challenges of preserving modernist concrete

¹ Associate Principal, Wiss, Janney, Elstner Associates, Los Angeles, California, United States
² Principal, Wiss, Janney, Elstner Associates, Chicago, Illinois, United States

^* Corresponding author: aharrer@wje.com

Abstract

Exposed architectural concrete is often a defining characteristic of modernist structures. Concrete, like other construction materials, eventually deteriorates over time and with exposure to environmental factors. With any historic structure, challenges exist in the development of an appropriately sensitive rehabilitation strategy to address existing distress, including structural repairs, use of compatible materials, development of repair procedures without unnecessary removal of historic material, and sustainable practices, as well as to meet the requirements of governing standards or jurisdictions. It is important to understand the structure’s construction, including material constituents of the concrete, unique characteristics, and extent and causes of deterioration, as well as project requirements and goals. Following a condition assessment, the rehabilitation strategy can be developed, taking into account the sensitive nature of the structure. Appropriateness and compatibility of repairs, together with technical soundness, are key to the success of the repair design. In addition, poor or incomplete repairs will have a minimal service life and can result in additional distress or other problems with the structure. This paper will describe challenges encountered in the preservation of modern concrete structures, focusing on architectural concrete. Case studies of several iconic modernist concrete structures, including the Salk Institute for Biological Studies in La Jolla, California, for which the authors have developed that highlight approaches to address these challenges.