Performance of patch repairs on historic concrete structures: a preliminary assessment

Abstract

Carrying out patch repairs to historic concrete buildings and structures needs to be done carefully if their cultural value and significance is to be maintained. This often means repairs using custom designed materials and mixes for compatibility with the original concrete, and with great care paid to good workmanship. But with most repairs, commercial mixes are used which are not compatible with the host concrete but are justified because they adhere well, cure quickly and require limited skills to implement. A research collaboration has been established to test the performance of both approaches. The Performance Evaluation of Patch Repairs on Historic Concrete Structures (PEPS) began in 2018 and is a collaboration between the Getty Conservation Institute, Historic England and the Laboratoire de Recherche des Monuments Historiques. Its purpose is also to better understand key design and specification parameters and application methods. The research is based on assessing case studies in USA, England and France within a variety of climatic and environmental conditions, typologies and repair materials. This paper will present the methodology adopted to evaluate the repairs in the first phase. This will also include historical research on the specification and application of the repairs, preliminary field assessment and some testing.