The dissertation is devoted to the comparative analysis of work and strainstressed state (SSS) of steel reinforced concrete slabs with different types of profiled
steel sheeting.
The actuality of theme was substantiated, the purpose and tasks of researches,
scientific novelty and practical value of work were formulated, its general
characteristic and connection with scientific programs were presented.
The possibility of using modern numerical methods and software complexes for
the calculation of steel reinforced concrete slabs with profiled steel sheeting, in
particular the finite element method (FEM), was investigated. The comparative
analysis of modern software systems implementing FEM is carried out.
20
The research of SSS of steel reinforced concrete slabs with profiled steel
sheeting by analytical methods in a mathematical shear model taking into account the
deplanation of cross-sections is devoted.
Improvement of known analytical models of SSS (mathematical shear model) in
the framework of these studies was carried out in two stages: first of all the classic
model based on the hypothesis of plane cross sections and taking into account the
heterogeneity of the cross-section, was adapted to describe the SSS of steel reinforced
concrete slabs; at the second stage of the research the functions of distribution of
stresses at the height of the cross section were obtained, as well as the ratio for
determining the stresses and coefficients of stiffness with taking into account the
deformations of shear.
The experimental research of steel reinforced concrete slabs with profiled steel
sheeting and their components, the purpose of which was to obtain data on the
peculiarities of work under short-time loads, the peculiarities of the SSS, character of
SSS, the strength and deformability of this type, structural elements, as well as the
verification of analytical and numerical models for their calculation are devoted. The
chapter contains data on the accepted methodology, tasks and experimental research
program, as well as the analysis of the results.
During the experiment, a special attention was paid to determining the physical
and mechanical properties of materials of experimental samples – profiled steel
sheeting and flexible reinforcement, reinforced concrete and concrete contact with
profiled steel sheeting with punching. For this purpose, a series of prototypes
consisting of steel sheets, cut from profiled steel sheeting, and a concrete mixture,
which poured into molds fixed on a steel sheet symmetrically on both sides (for
obtaining conditions of pure shear) was made. The experiment ended when at least
one of the concrete cubes were stripped off a steel sheet.
In the result of experimental researches, the efficiency of the application of the
anchor structures proposed by the author the constructions of anchoring in the form
of punching on the profiled steel sheeting was confirmed in comparison with the slab
without additional anchoring facilities), which can be recommended as the main ones
in the design of combined structural elements combining materials whose physical
and mechanical characteristics significantly different.
For the creation of finite-element models, the original drawings of profiled steel
sheeting and composite steel reinforced concrete slabs were used. The procedure for
constructing finite-element models envisaged the development of basic threedimensional geometric models of profiled steel sheeting and slabs.
Linear and nonlinear static calculations were performed for all models.
The results of the FEM calculations were confirmed by the conclusion obtained
in the experimental researches that the most effective is the anchoring method, using
anchors in the form of punching, which are located in a horizontal plane and intersect
the walls of the profiled steel sheeting.
On the basis of the conducted researches, general conclusions on the application,
modeling and calculation of steel reinforced concrete slabs with profiled steel
sheeting are formulated, and their results were implemented during the construction
of a shopping and entertainment сenter in Kyiv.
Keywords: stress-strain state, reinforced slab with profiled steel sheeting,
reinforced concrete, finite element method (FEM), shear, deplanation, anchoring,
punching.
