Frameless arch covering: practice of application

Introduction. The research examines frameless arched buildings made of cold-formed steel profiles, which have gained widespread popularity due to their simplicity of production and installation, low cost, and technological efficiency. The drawbacks encompass the absence of regulatory and technical documentation, as well as design flaws, which frequently result in failures.

The aim of research is to analyze the load-bearing capacity of frameless arched roofs and develop recommendations for their design, construction, and operation to prevent failures.

Materials and Methods. To determine the load-bearing capacity of a frameless arched roof, the arch was analysed by numerical modelling in a finite element software suite, employing shell finite elements that accommodate both geometric nonlinearity (large deformations, displacements, etc.) and physical nonlinearity. The profile geometry was modeled using shell finite elements, incorporating all characteristics of the cross-section, taking into account the transverse corrugations on the shelf and the wall, as well as the unevenness of their height (on the wall). The calculations were carried out in a geometrically and physically nonlinear formulation of the problem.
This paper outlines the structural characteristics of frameless arched edifices, encompassing the materials used, profile varieties, geometric specifications, and their respective applications.  The limitations associated with the functioning of such structures are also delineated.

Research outcomes. The analysis of a failure case is provided: the failure of an arched structure under a snow load that was below the regulation threshold. Characteristic errors include inconsistencies between design models and actual operating conditions, neglect of geometric nonlinearity, and improper installation practices. The analysis showed that design and operation of frameless buildings, without consideration of their unique characteristics and the lack of an appropriate regulatory framework, may result in structural problems.

Conclusions. In order to prevent failures, it is proposed to develop a unified methodology for calculating structures, incorporate it into regulatory documents, and develop technical specifications for each profile type.