Welded reinforcement for concrete structure - has rolled ribs subjected to cold rolling without impairing notch strength

摘要

The ribbed reinforcing bar is for concrete structures, used for fabricating reinforcing mats by spot welding. The bars are produced by hot rolling with subsequent cold calibration. The rod is provided with three parallel flats superimposed by ribs at an angle to the bar centre line. The unimpaired notch impact strength is achieved by subjecting the head of the ribs during the cold rolling to a pressure below the critical pressure, at which a deterioration of the notch impact strength does not occur.