Analysis of possible failure mechanisms of loop joints in reinforced concrete monolithic structures
https://doi.org/10.37538/0005-9889-2025-2(627)-5-15
EDN: OSIWVY
Abstract
Introduction. This paper examines analytical methods for calculating of loop joints in monolithic reinforced concrete structures. The main focus is on analyzing failure mechanisms that differ from classical reinforcement overlap and determining structural strength conditions.
Aim. To identify the main possible failure mechanisms of loop joints, develop an analytical model of their behavior, and propose an improved calculation methodology to ensure the reliability of connections.
Materials and methods. The study is based on an analysis of existing calculation methods as well as the results of numerical and full-scale experiments. Three main failure mechanisms are considered: local concrete crushing, failure of the concrete core between loops, and loss of reinforcement bond with concrete. A frame-bar model is proposed to describe force transmission through the concrete core.
Results. Based on the analysis of physical and numerical experiment data, as well as international experience, additions and alternative solutions to the currently adopted methodology are proposed.
Conclusions. A comparative analysis of calculation results using different methods revealed some discrepancies. For further development and refinement of analytical calculation methods for the concrete core of loop joints, continued physical and numerical experimental studies are recommended.
About the Authors
A. N. Mamin
JSC "TsNIIPromzdaniy"; Moscow State University of Civil Engineering (National Research University)
Russian Federation
Russian Federation
Aleksandr N. Mamin*, Dr. Sci. (Engineering), Professor, Head of OZS No. 1 Department, JSC "TsNIIPromzdaniy"; Professor at the Department of "Reinforced Concrete and Masonry Structures", Moscow State University of Civil Engineering (National Research University), Moscow
e-mail: otozs@yandex.ru
tel.: +7 (903) 794-64-39
K. V. Avdeev
JSC "TsNIIPromzdaniy"
Russian Federation
Russian Federation
Kirill V. Avdeev, Deputy Director General, Chief Engineer, JSC "TsNIIPromzdaniy", Moscow
e-mail: 6136133@mail.ru
S. A. Zenin
Research Institute of Concrete and Reinforced Concrete named after A.A. Gvozdev, JSC Research Center of Construction
Russian Federation
Russian Federation
Sergey A. Zenin, Cand. Sci. (Engineering), Head of the Laboratory of the Theory of Reinforced Concrete and Constructive Systems, Research Institute of Concrete and Reinforced Concrete Structures named after A.A. Gvozdev, JSC Research Center of Construction, Moscow
e-mail: lab01@mail.ru
A. A. Bammatov
JSC "TsNIIPromzdaniy"; JSC "Severstal Management"
Russian Federation
Russian Federation
Arslan A. Bammatov, Leading Expert, JSC "Severstal Management", Moscow
e-mail: a.bammatof@yandex.ru
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Review
For citations:
Mamin A.N., Avdeev K.V., Zenin S.A., Bammatov A.A. Analysis of possible failure mechanisms of loop joints in reinforced concrete monolithic structures. Concrete and Reinforced Concrete. 2025;627(2):5-15. (In Russ.) https://doi.org/10.37538/0005-9889-2025-2(627)-5-15. EDN: OSIWVY
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