Reinforced concrete buildings lacking seismic isolation need reinforcement in earthquake-prone Japan. Guidelines for reinforcing them, and thereby conserving their historical value, have been set. This paper evaluates reinforcement efforts, focusing on reversibility and original structures, distinctions between the structures and their reinforcements. 76 modern reinforced concrete buildings are considered.
Reinforcements must be distinct from original structures; otherwise the line between original structures and their reinforcements can become blurred. Article 12 of the Venice Charter addresses this concern. Additionally, historical monuments reflect cultural diversity. Reinforcements applied to concrete buildings likewise require originality of design, a fact also recognized in restoration guidelines. A third aspect of these structures is the features requiring reinforcement. Weakened points and other problems of a building must be truly reinforced, not simply disguised.
Keeping the above aspects in mind, this paper offers advice on how to best reinforce historical reinforced concrete buildings so that people will enjoy them well into the future.