Re-designing demolished Cultural Heritage. A study of a thin shell design for earthquake-destroyed churches in Finiq municipality
Author: Albi Alliaj
Affiliation: PhD IDAUP/ POLIS University
Abstract
This scientific study involves the methods for the design of thin shells on top of cultural heritage buildings that have already collapsed in the municipality of Finiq. The studied object is an orthodox church in Finiq municipality, in Leshnica e Sipërme village. Its roof has already collapsed because of an earthquake and the degradation of the mate- rial. However, the dominant part of the structure, such as walls and columns, is still standing, even though need reinforcement. The maximum span of the roof is long enough to justify the use of a thin shell structure. This study tries to find an elegant solution to this problem, which combines structural beauty with the efficiency of the design and building process, defined as important aspects of a good structural design. The methods proposed for the reconstruction of the existing part of the church are the restoration methods used for monuments in Albania. The propositions take into consideration the state of degradation of each structural element. The primary goal for the reconstruction of the reinforcing elements is that they will not affect the primary function of the building and to restore and keep the cultural heritage values of the object. The pre-design of the roof is made using non-linear analyses. The shape of the new roof and its thickness are chosen to use the Hanging Model Analysis, the Sanders-Koiter equations, the Membrane Theory and a buckling analysis using the software Karamba. The designing of rigid joints, which connect the roof with the other part of the structure, is made so that the entire structure could work and behave as one, while it is loaded during its lifespan. The shell is designed as a pre-fabricated one using UHPC material and divided into panels with rigid joints between them. The analysis and validation of the design of the structure is made with the Load Capacity Analysis in the Ultimate Limit State of it using the software Karamba. The paper concludes by highlighting the importance of recovering the already degraded cultural heritage structures and the role that technology can play in ensuring the integration of the old part of the structure with the new one.
Keywords: Thin shell, restoration, structural analysis.
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