SUSCEPTIBILITY OF PRESTRESSING STEEL WIRES TO HYDROGEN-ASSISTED CRACKING IN ALKALINE MEDIA SIMULATING CONCRETE PORE SOLUTIONS

摘要

The susceptibility to hydrogen-assisted cracking of cold-drawn pearlitic steel wires used as reinforcement in concrete is studied in alkaline media modeling pore liquids in concrete. The prestressing steel is established to become susceptible to hydrogen embrittlement under potentials of -1.1 V (SCE). The maximum fracture load, as well as the elongation to fracture, decrease as the cathodic potential increases; the effect is more noticeable for slow strain rates. The fracture mechanism in aggressive media differs from the fracture mechanism in air. The role of surface defects in the environment-assisted cracking is discussed.