The pathological image of the monument (both the historical and the current ones), as well as the fact that the Katholikon is built in a tectonically active area, suggest that in addition to interventions that are necessary for the repair of observed damages, adequate measures should be taken with the aim to alleviate the inherent vulnerability of the structure and, thus, to improve its future behaviour in some critical regions. Due to the high values ofthe monument, its vulnerability and the fact that interventions should not drastically alter the initial structural system, the decision was taken to investigate thoroughly its structural behaviour. To this end additional data were necessary in order to avoid conservative assumptions (both for actions and resistances). Such assumptions would lead to extensive interventions that might not be needed and that would inevitably alter the architectural value of the monument.
On the basis of the aforementioned reasoning, it was decided to implement the structural restoration works in two phases, thus giving the possibility for these additional data to be collected. The first phase of works comprises all those considered necessary to achieve the better possible repair and strengthening of masonry elements (mainly stitching and deep re-pointing where necessary, systematic grouting injections, local reconstructions, etc). The second phase concerns the various strengthening interventions that will be designed and selected as optimum, in order to improve the overall behaviour of the whole building (such as installation of ties, diaphragmatic structures in the extrados of the vaults and the exonarthex, etc). Due to the type and extend of damages, it was judged as absolutely necessary the first phase of interventions to be applied in priority, in order to avoid further deterioration of damages, which could lead to a total disruption of continuity and even local collapses, in case of further seismic events. Besides, during this first phase of works a better structural survey of invisible parts of the monument (internal face of masonry elements, extrados of vaults) could be possible.
The implementation of the first phase of structural restoration interventions has been now accomplished, together with the most of the research and investigations undertaken to support both phases of works, briefly presented below. Preliminary proposals for the second phase ofinterventions have also been approved, but their final design is still under elaboration.
Was this article helpful?