Experimental and analytical assessment of the erection state of large-span reinforced concrete shell structures

This paper presents an experimental and analytical study of the erection state of large-span reinforced concrete shell structures for unique buildings. The research focuses on the stress-strain behavior of shell systems during installation, dismantling of temporary erection devices, and transition to the operational stage. Experimental modeling was carried out on large-scale models with scales of 1:10 and 1:4 for shells with spans of 48 m, 96 m, and more. Composite shells assembled from prefabricated and enlarged erection elements were investigated for different erection and dismantling sequences. The stress-strain state was evaluated under self-weight and installation loads, and the obtained results were compared with calculation data based on shell theory relations and engineering modeling procedures. It was established that the most rational dismantling sequence consists in first lowering the temporary posts and beams and then removing the forces in the temporary ties. This sequence reduces the forces in the ties by 21-34 % and ensures a more favorable stress state of the shell elements. For the studied shell configurations, labor costs were reduced by 26 %, while the weight of the erection equipment set was reduced by 2.4 times compared with traditional assembly methods. The discrepancy between experimental and calculated ultimate forces did not exceed 8.8 %. The proposed approach can be used in the design and construction practice of unique large-span buildings to improve erection safety, structural efficiency, and reliability.