- BUILDING STRUCTURES, BUILDINGS AND FACILITIES
- Bearing Capacity Of Strength Of An Axially-Compressed I-Beam Rod Under Restrained Torsion
- UDC 624.046.3 DOI: 10.33622/0869-7019.2020.09.21-27

**Alexander R. TUSNIN**, e-mail: tusninar@mgsu.ru

**Amirshokh Kh. ABDURAKHMONOV**, e-mail: 3andya@gmail.com

Moscow State University of Civil Engineering (National Research University), Yaroslavskoe shosse, 26, Moscow 129337, Russian Federation

**Abstract**. The bearing capacity of an axially-compressed thin-walled rod of open cross section under constrained torsion is considered. Theoretical and numerical calculations of axially-compressed cantilever beams of various flexibilities under the action of axial force and bi-moment are presented. A theoretical and numerical analysis of the influence of the bi-moment on the bearing capacity of an axially-compressed thin-walled cantilever rod with an open cross section under the restrained torsion is performed. For the theoretical estimation of the rod stability, the nonlinear dependence of the shelf deflections under compression and torsion is taken into account. The dependence of deformations of the loose end of the shelf of the cantilever rod on the angular twist under the action of the bi-moment is established. An analytical formula for testing the bearing capacity of axially-compressed rods is proposed and the stability coefficient for restrained torsion with an I-beam cross-section for cantilever and propped cantilever rods is determined. A method of numerical calculation in a finite element setting is presented, taking into account the geometric and physical nonlinearity of the system for cantilevered rods. Theoretical and numerical results are compared, the possibility of using the numerical modeling to assess the stability of axially-compressed thin-walled rods of open cross section under the restrained torsion is established.

**Key words**: thin-walled rod of open cross section, I-beam rod, flexibility, bi-moment, ultimate stress, , stability coefficient. - REFERENCES

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