- BUILDING STRUCTURES, BUILDINGS AND FACILITIES
- Deflections and Frequencies of Own Fluctuations of a System of Cross Trusses on a Square Plan with Various Schemes of Bearing
- UDC 624.014

**Andrey V. TURKOV**, e-mail: aturkov@bk.ru

Southwest State University, ul. 50 let Oktyabrya, 94, Kursk 305040, Russian Federation

**Olga A. VETROVA**, e-mail: vetrovaoly@mail.ru

**Kirill V. MARFIN**, e-mail: marfinkirill@yandex.ru

Orel State University named after I. S. Turgenev, Komsomolskaya ul., 95, Orel 302026, Russian Federation

**Abstract**. The systems of cross steel trusses on a square plane as bearing structures of roofs (floors) of buildings and structures are presented. To assess the stiffness of the coating structures, studies of the stiffness parameters of the system of cross steel trusses - frequencies of natural transverse vibrations and maximum deflections were carried out. The relationship between the fundamental frequency of free transverse oscillations of the systems of cross steel trusses on the square plane and their maximum deflections under the action of uniformly distributed load depending on the system support scheme is considered. Dependences of deflections and frequencies of transverse oscillations on the ratio of the number of supports on the short side of the structure to the number of supports on the long side are constructed. It is shown that with a decrease in the number of supports, there is an increase in deflections, a decrease in the free-oscillation rate, as well as a remoteness of the design coefficient from its analytical value for rectangular isotropic plates of constant thickness. The article is of scientific interest for specialists assessing the rigidity of structures of regular structure.

**Key words**: cross truss system, static load, natural frequency, maximum deflection, support scheme. - REFERENCES

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