CAUSES, MECHANISMS AND MEASUREMENT OF DAMAGE IN CULTURAL HERITAGE MATERIALS: THE STATE OF THE ART: CONCRETE STRUCTURES

Abstract

Steel reinforced and prestressed concrete structures are increasingly being included in the protection of monuments. This adds to the importance of concrete as a building material in the field of monument maintenance. Under normal atmospheric conditions concrete is a durable building material. This is proved by well preserved building structures dating back to Roman times. If the concrete is reinforced with steel, the behaviour of the steel has to be specifically taken into account. Today's state of the art enables durable steel reinforced and prestressed concrete structures to be erected for normal atmospheric conditions. Suggestions are given for the production of durable concrete. However, particularly aggressive conditions may result in chemical attack, i.e. concrete corrosion. In rare cases even concrete ingredients may cause damaging reactions. A brief survey of concrete corrosion is given. Preventive concrete protection is necessary where the concrete produced is not in accordance with the standards or under particularly aggressive environmental conditions. In the event of damage occuring in concrete structures a detailed damage diagnosis has to be established prior to repair work. This diagnosis includes investigations of the history of the structure, examinations on the spot and in the laboratory. It results in the recommendation of repair measures.