Gabitov A.I.

Doctor of Engineering, Professor of Building Structures Department, Ufa State Petroleum Technological University, Russia

Strengthening of monolithic concrete slabs against pushing

https://doi.org/10.58224/2618-7183-2025-8-2-4
Аннотация
Significant stress concentrations occur at the interface of floor slabs and columns in widely used monolithic reinforced concrete beamless frames. Therefore, the strength of the floor slabs must be checked for pushing under the loads from columns, bearing walls or stiffening diaphragms. The analysis of engineering solution of beamless monolithic reinforced concrete slabs of the administration nine-storey building with frame-walled load-bearing system is made. The strength thereof for pushing is found to be not provided under the given loads in a number of cases, due to this, experimental studies of strengthening the near-column areas of floor slabs have been carried out. When restoring the structures that suffered defects and damages in the course of their operation, composite materials having high tensile strength, low weight, constructibility and resistance to aggressive influence are widely used. The presented method for strengthening the near-column areas of floor slabs for ensuring their pushing strength with the use of chemical anchors has been developed, and a comparative analysis of the calculation results of the near-column areas of floor slabs with the adopted strengthening method with the results of experimental studies of slab fragments has been carried out. The operating conditions of the near-column areas of the floor slab have been simulated under the test method, and the results of the experimental samples testing are presented. All samples were found to have been destroyed by pushing through, with the destruction being of a plastic nature. The results of assessing the application of transverse reinforcement to the load-carrying capacity of the slab on pushing-through are presented. The results of experimental studies on assessing the pushing strength of extreme parts of monolithic floor slabs with columns reinforced with transverse glued-in reinforcement have shown good efficiency.
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Investigation of the stress-strain state of domical masonry vaults

https://doi.org/10.58224/2618-7183-2023-6-6-6
Аннотация
The results of analytical study of stress-strain state of one of the varieties of vaults erected in various function buildings, i.e. domical masonry vaults covering Orthodox churches, are presented in this article. Due to the ongoing restoration of architectural monuments and religious buildings, as well as in connection with the construction of such facilities as Orthodox churches, the study of stress-strain state of masonry arches and vaults has become especially important in recent decades. Despite the rapid development of new building technologies in the construction of temples, use of these new technologies is shown to be limited and focused on the use of traditional materials. The current level of engineering of building structures with the use of software enables to significantly improve the calculation models and to obtain more reliable results, in particular for the structures under consideration. The domical vault considered herein is formed by wall extensions inclined along a given curve, converging in a horizontal crown under rectangular plan or in one point under square plan. The authors of the article have performed calculations of vaults in both linear and nonlinear formulations, with the results thereunder the forces and deformations of vaults have been analyzed. As a result profiles of vertical pressures and lateral pressures of the vault mounting groups, isopoles of principal stresses, vertical displacements, bending moments and normal forces were calculated.
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