Calculation methods for reinforced concrete structures at the beginning of the 20th century: The Modernissimo Theater in Bologna

Palazzo Ronzani represents a junction between local tradition and modernity as it collects different construction solutions: a reinforced concrete frame, unreinforced concrete masonry, and load-bearing masonry. The structural design followed the Hennebique system, but the archival documentation contains a limited number of documents about the structural design, and no structural calculation report to confirm the adoption of the system. The paper focuses on the study of its structural calculation, simulating the procedure that technicians must undertake in intervening on buildings dated to the beginning of the 20th century, with calculation and construction documentation often missing. The restoration site of the theater offered the opportunity to carry out specialized structural surveys, bringing to light the traditional stirrups and the huge smooth iron reinforcements. The theoretical simulation of the calculation procedure has highlighted the correspondence between the patent and the real situation, confirming the adoption of the system and its excellent structural performance.