Accuracy assessment of various regulatory methods for calculating the strength of inclined sections of reinforced concrete structures under the action of shear force

Introduction. The mechanism of reinforced concrete structures failure under the action of a transverse force has been the subject of domestic and foreign research for many decades. The key factors influencing the bearing capacity of the structure within the framework of this mechanism of destruction are: the shape and dimensions of the cross-section of the structure, the strength characteristics of concrete and reinforcement, the span-to-depth ratio, the amount of longitudinal reinforcement in the tensile zone, and the amount of transverse reinforcement. Incorrect consideration of these factors negatively affects the accuracy of design methods for inclined sections of reinforced concrete structures under the action of transverse forces.

Aim. Assessment of the accuracy of methods for calculating reinforced concrete structures in inclined sections from the action of transverse forces presented in various regulatory documents.

Materials and methods. To assess the accuracy of the calculation methods, a database was compiled, including the results of 1,183 laboratory tests of reinforced concrete structures, the destruction of which occurred along an inclined section. The accuracy is estimated by comparing the value of the maximum transverse force obtained in laboratory tests and the theoretical value obtained using the calculation method under consideration.

Results. The paper presents the results of comparing the values of the ultimate shear force obtained in the framework of laboratory tests and using the considered calculation methods.

Conclusions. A comparative analysis of the design methods has shown that in certain cases the methodology set out in SP 63.13330.2018 is less accurate than the methods provided in foreign codes. In this regard, the task of improving the shear design method for reinforced concrete structures presented in SP 63.13330.2018 appears to be relevant. Refinement of the calculation methodology will increase its accuracy and expand its scope of application.

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