Abstract:

38 prestressed concrete slabs and beams after the elevated temperature experience were smashed and 481 tensile test specimens from the prestressing steel wire and 489 from nonprestressed steel bar were prepared to investigate the mechanical properties of these materials after the elevated temperature experience. The specimens were tested on mechanical properties, and the change behaviors of their related strength, elastic modulus, and specific elongation at rupture, as well as their stressstrain curves were obtained. The results can be used to analyze the fire resistance of the prestressed structures. The test results show that the strength of the prestressing steel wire after the elevated temperature experience is a little lower than that of wire without this experience, but for the nonprestressed steel bar, the elevated temperature experience has hardly effect on its strength.

Key words: civil engineering, prestressing steel wire, nonprestressed steel bar, mechanical property