High-Capacity Weldless Joining of Reinforcing Bars with Six-Start Profile

Abstract

Object of the utility model: A method for the weldless butt joining of reinforcing bars using a six-start spatial mechanical interlock. Field of application: The utility model relates to the field of construction, specifically to technologies for reinforcing concrete structures and the erection of buildings and structural frameworks. Essence of the utility model: The method consists of machining six-start paraboloidal helical spline profiles on the ends of the reinforcing bars: external profiles on one side (T-type) and internal profiles on the other (M-type). Fixation is achieved through thermal interference fitting: the T-type bar is pre-cooled in a cryogenic medium, after which it is freely threaded into the M-type bar. The reverse thermal expansion of the metal of the T-type bar creates a tight spatial intertwining of the six protrusions and grooves. Technical result: The proposed method provides a radical increase in the contact area of the mating surfaces, perfect self-centering of the components, and a symmetrical distribution of extreme tensile and torsional loads. This guarantees ultra-high load-bearing capacity of the connection while preserving the original structural integrity of the metal by completely abandoning the welding process. 6 illustrations.