MODEL AND RESULTS OF SCIENTIFIC AND TECHNICAL SUPPORT FOR REPAIR AND RESTORATION WORKS AT THE MONUMENT OF URBAN PLANNING AND ARCHITECTURE THE RUSOV HOUSE IN ODESA

Abstract

The house of the Odesa entrepreneur A. Rusov is one of the dominant architectural features of the historic development in the central part of the city. The main causes that led to the deterioration and partial loss of individual elements of the building include: reconstruction and alterations to the internal layout, fires, the absence of major and routine repairs, differential settlement, and other factors. As a result of fire exposure and fire suppression activities, the building was left virtually without its principal stiffness elements ‒ the floor diaphragms ‒ which, in turn, resulted in a hazardous unsupported height of the remaining walls. The above factors contributed to the structural fragmentation of the building into separate sections. In 2018-2019, a sequential model of scientific and technical support was implemented during the repair and restoration works at the Rusov House in order to ensure its load-bearing capacity and durability while preserving its authenticity. One of the areas of scientific and technical support during the repair and restoration works involved monitoring the condition of Group "A" building structures based on the results of numerical modelling and dynamic surveys. Verification of the computational model was performed by comparing the frequencies of the lower natural vibration modes obtained from modal analysis with those measured directly in situ on the actual structure. During the foundation strengthening works, a decrease in the natural frequencies (an increase in the periods) of the first natural vibration modes was observed at the monitored points, without changes in their mode shapes, indicating a reduction in the stiffness of the structural elements while the mass values and structural geometry remained unchanged. As the restoration of the floor structures acting as rigid diaphragms progressed, a "convergence" of the measured values was observed, indicating the development of integrated structural behaviour among the building sections being connected. Based on the monitoring results and analysis of the computational models, recommendations were developed for adjusting the design solutions for the floor structures. Their implementation improved the structural efficiency of these elements.