Criteria and technologies for the structural repair and strengthening of architectural and archeological heritage

The preservation and valorisation of architectural heritage are becoming more and more a major social and economic issue in many countries. This implies, of course, that a “minimum accepted level” of structural safety is to be ensured of historical construction typologies: several “new challenges” to structural engineers, in consideration of the original structural consistency of Cultural Heritage buildings, frequently exposed to severe environmental hazards (like earthquake). Problems range from the definition and choice of the “conventional” safety level, to the methodologies that can be used to perform reliable structural analyses and safety verifications – as modern ones are frequently not suitable for the construction under consideration – and to the selection, design and execution of appropriate materials and interventions techniques aimed to repair and strengthen the built heritage while preserving its cultural, historic, artistic values. Many efforts have been dedicated in the recent past to make specific tools, to appropriately tackle the above mentioned problems, available to practitioner engineers and architects: new generations of codes and codes of practice are now also available, specifically for historic constructions. A short review of all the mentioned aspects is presented in the paper, making specific reference to research activities, practical applications and to the recent evolution of codes and guidelines.