The article describes four developed designs of samples of joints of solid wood elements on aluminum linings. They made it possible to simulate the operation of real connections of the main and secondary beams, as well as crossbars and columns. Tests of connection samples were carried out, one of the four developed variants of sample designs was selected that most fully reflects the actual work of real joints of wooden elements. The strength and deformation characteristics of the joint, the upper boundary of the elastic work area (VGOUR) of the joint are determined. Based on the conducted research, the peculiarities of the work of the studied compounds were determined, a sample of the connection of a wooden element with a metal overlay was developed, which allowed the development of measures aimed at increasing the bearing capacity and reducing the deformability of the studied compounds without significant material costs associated with the purchase of expensive SHERPA linings.

Keywords: solid wood, metal slips, testing of joint specimens, joint bearing capacity, joint deformability, upper limit of the elastic work region, full deformation, permanent deformation, elastic deformation, safety factor

The construction of public buildings from a metal frame is always associated with the search for a rational constructive solution that meets not only the dependability requirements, safety, but also architectural and design solutions. Often, the solution to the problem of rationalization of roof construction in public buildings is the use of arched combined systems, since such systems have a number of advantages over simple arches: the survivability of combined systems is higher than simple ones, the possibility of creating complex, architecturally expressive spatial structures, lower material consumption, high load-carrying ability with relatively low weight, etc. The aim of the research is to find a rational construction solution for two arch-cable systems (Hud type system and Radial type system) by comparing in terms of the minimum internal forces, displacements and metal intensity at different ratios of the arch boom and span. Based on the calculation results in the Lira SAPR 2020 software, the most unfavorable loads combinations were determined, deformation schemes of arch systems, displacements, moments and forces were obtained, sections of arches and ties were selected. From ten arched structures of two types considered with different ratios of arch boom to span, the Hub type system with the ratio of arch boom to span f/L = 1/3 and Radial type system with the ratio of boom to span f/L = 1/4 showed the best result in terms of efficient operation and metal intensity.

Keywords: combined systems, arch-cable constructions, simulation of prestress, hub type s

Arched constructions of the roofs of span-type buildings are very cost-effective in comparison with beam and frame systems. In many cases, the high architectural qualities of arch structures allow one to obtain expressive interiors of large halls. At the same time, the construction of long span buildings is always associated with high risks, high security requirements for such buildings, and, consequently, increased requirements for reliability to load-bearing structures, including possible local destructions. Actual becomes the issue of ensuring the survivability of building structures in general, and the construction of roofs for long span buildings in particular. To analyze the survivability properties of shallow arched coverings, a number of constructive solutions of arched constructions of various types are considered. The work of arch structures of various types with possible local caving of a number of elements is considered. Five design schemes of arched constructions are presented, and work of each of them is considered at exclusion of the most loaded elements. In particular, the work of the arch structure with fan-shaped tie system with a split upper belt is considered. A comparative analysis of the survivability properties of the constructive solutions under consideration is presented.

Keywords: arched covers, arch structure with fan-shaped tie system, survivability, local destruction, constructive solutions, long span roofs, progressive collapse