A New Method for Assessing Compatibility of Consolidation Procedures with Conservation Principles: Intervention Quality Index (IQI)

Abstract

In current times, built heritage is being lost at an alarming rate due to natural and human hazards. Policies for its protection and rehabilitation involve, among other things, challenges related to the refinement of suitable structural strengthening approaches. The arduous balance between gaining acceptable safety levels for occupants without deploying intrusive devices, inconsistent with conservation principles such as those of the ICOMOS charters, is not a simple task. The interest and efforts of the scientific community in this regard have been increasing for decades, but still, it is the structural professional´s responsibility and experience which must define this arduous balance on a case-to-case basis. This study addresses the question: How can the quality of structural rehabilitation interventions be assessed in light of conservation principles such as those given by ICOMOS?Here, a preliminary method -called "Intervention Quality Index" (IQI) method is proposed. It assesses the restoration intervention quality in relation to: (i) the level of compliance given by the conservation´s principle score (conservation´s factor, CF); and (ii) the current state of conservation of the monument (safety factor of building considering the seismic intensity, Δ s ). The IQI method considers the compliance level of the designed reinforcement with conservation principle, formalized through the fulfillment of a category, i.e. respected, partially respected, and not respected. Then, these judgments are translated into scores and statistically evaluated. Scores are attributed in relation to the relevance of the fulfillment of a certain conservation principle (authenticity, minimal intervention and intrusiveness, compatibility, recognizability and reversibility) for the seismic structural safety point of view. Preliminary results show that an effective employment of traditional earthquake-resistant practices together with a wise use of modern retrofit strategies allow for the preservation and reinforcement of built heritage without harming its identity.