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The paper provides a brief overview of domestic and foreign guidelines (manuals) for the design of composite steel and concrete structures: steel-concrete slabs on profiled flooring, combined beams, and columns with rigid reinforcement. The necessity of creation of the actual manual corresponding to the modernlevel of development of construction science, normative documents and design practiceslinked to the new formulary SP 266.1325800.2016 is proved. It will facilitate the design, reduce labor expenditures and improve the reliability of composite steel and concrete structures. The new guidance provides general recommendations for the design of composite steel and concrete structures and the basic regulations for the calculations. The new guidance describes recommendations for modeling of composite steel and concrete structures and elements in the calculated complexes, the recommendations for calculation of combined beams fully concreting rectangular and T-section, partially concreting along with support slab on the lower flange of the beam, columns with rigid reinforcement, shear a connection of composite beams. Recommendations on the registration of creep, shrinkage and crack formation in the appointment of the modulus of elasticity are given. Recommendations on the use of diagrams of the state of concrete, reinforcement, and steel in the calculation of steel-concrete elements on a nonlinear deformation model are given. Recommendations on the use of the range of sheet flooring for steel-reinforced concrete slabs, as well as metal profiles as steel beams and rigid reinforcement in the cross sections of columns and combined beams, are presented. Recommendations on a design of units and details of composite steel and concrete structures are given, refined recommendations on buffer are presented. The examples of connection of steel beams with columns with rigid reinforcement are given. The examples of calculation of composite steel and concrete structures taking subject to the recommendations given in the Manual are presented.

The paper presents a brief review of test experiments with models of steel-concrete beams made of high-strength concretes. The description is given to models and features of the applied materials. Numerical modeling and calculations are performed for steel-concrete beams. The modeling is performed in two versions: with and without the steel-concrete contact interaction. The calculation results are given numerically and graphically, and loads corresponding to the limiting bearing capacity, vertical displacements, crack opening width, height of the selected compressed zone are obtained. All parameters are evaluated and compared with the experimental data. Numerical and experimental models of destruction are compared. The obtained simulation and numerical results are compared.

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A brief overview of the issues of aggregate work of components of the composite steel and concrete section is made. It is presented various options for the layout of the cross-section of beams used in the practice of design. A review of the design of the regulatory documents regarding the issues of adhesion of cross-section el­ements is performed. The characteristic of experimental models is given. The features of destruction of models are shown. The reasons of the destruction are analyzed. The case of the loss of the bearing capacity of the ele­ment due to relaxation (loss) of adhesion at the steel - concrete interaction boundary is considered. Various shear surfaces of the concrete section are given. Calculations of the bearing capacity of the composite steel - concrete beams for each computational surface were performed, the obtained results were evaluated. Conclusions have been made on the question of ensuring aggregate work in case of composite steel - concrete beams with a fully encased steel core.