377 It is proposed the computational model of the dynamic loading in longitudinal and transverse reinforcement at instant emergence of the spatial сrack in reinforced concrete constructions under the action of torsion with bending. The dependences have been obtained for the determination of stresses in stretched reinforcement, vertical and horizontal reinforcement stirrups in cross section with a crack.

No abstract

On an energy basis, without involving the apparatus of dynamics of structures, an analytical solution of the problem was obtained to determine the dynamic additional loads in complexly stressed reinforced concrete elements of multi-storey frames in a transcendental state caused by special emergency effects. The stress state, crack patterns and fracture patterns in the crossbars of the considered frame structures are determined by the complex stress state of the frame elements caused by the combined action of torsional and bending moments. The assessment of the bearing capacity of such structures was carried out by the diagram method based on the use of energy ratios in the structural elements before and after a special impact, which makes it possible to determine the maximum dynamic deformations, curvatures and forces in the first half-wave of vibrations using the results of nonlinear static calculations according to the primary and secondary design schemes.

The efficiency and competitiveness of transport, other things being equal, directly depends on improving the safety of the transportation process, which in turn depends on the actual technical condition and durability of the rolling stock. To solve problems of this type, it is proposed a set of solutions is proposed that increases the durability of especially critical friction units that affect the safety of operation of technical systems used in loading and unloading and transport processes. The proposed solutions are characterized by manufacturability, low resource consumption and versatility.

Marshalling yards are a key part of the transportation process. Their precise operation determines the efficiency and safety of the transportation process, which, other things being equal, depend on the durability and safety of cars in real conditions, including during sorting processes on slides. Currently, during the dissolution of trains on low-power slides, shoe braking is used. This is cost-effective, but provokes the formation of thermomechanical damage on the surface of the wheels. These damages are called one-way sliders. The formation of sliders leads to downtime of cars during repairs and to the cost of restoring or manufacturing new wheels. The article presents a study of the effect of wheel sliding on the rail on the nature of thermal and mechanical damage to the wheels of rolling stock.