Method of calculating the parameters of the thread and the geometric dimensions of the couplings of the mechanical splices of the reinforcement bars
Abstract
The method of calculating the geometric dimensions of the couplings, as well as the parameters of the rolled and cut cylindrical threads of the mechanical splices of the reinforcement bars is given. The calculation method allows you to select the geometric dimensions of connecting couplings made of different grades of steel for connecting reinforcement bars of different strength classes. The article discusses the calculation method that allows you to select the parameters of mechanical splices of reinforcement bars with both rolled and cut threads, which are fundamentally different from each other in terms of manufacturing method. The methodology is based on the principles of calculating the strength of a threaded rod with a nut loaded with an axial force, which is reflected in the design scheme of forces for determining the length of the coupling and the parameters of the thread of the ends of the reinforcement bars. The calculation method consists of determining the calculated diameter of the rolled or cut thread of the reinforcing bar and selecting the parameters according to GOST 24705–2004. The length of the coupling is determined by the shear and crease stresses. The outer diameter of the couplings is determined by taking into account the safety factor for the load, which takes into account the actual strength of the reinforcement bars. Based on the results of the calculation, a formula for determining the diameter of the stamp for the stamping of the end of the reinforcement bars before performing thread cutting is proposed. Comparison of the calculation results obtained by the proposed method with the parameters of mechanical connections of reinforcement bars with cut and rolled threads of known and approved manufacturers showed satisfactory convergence. The article will be useful for engineers, designers and manufacturers of mechanical connections of the reinforcement bars.
About the Author
V. V. Dyachkov
Research, Design and Technological Institute of Concrete and Reinforced Concrete named after A.A. Gvozdev “Research and Development Center “Stroitel’stvo” JSC
Russian Federation
Russian Federation
Candidate of Sciences (Engineering), Deputy Head of the Centre No. 3
e-mail: d_vv@mail.ru
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Review
For citations:
Dyachkov V.V. Method of calculating the parameters of the thread and the geometric dimensions of the couplings of the mechanical splices of the reinforcement bars. Concrete and Reinforced Concrete. 2021;603(1):24-29. (In Russ.)
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