Effect of hydrogen embrittlement on mechanical properties of non-stressed prestressing steel

The aim of this paper is to elucidate the effect of hydrogen on the structure of commonly used prestressed concrete steel strand (PC strand) of concrete bridges and other structures in the non-stressed state to determine the general behaviour of the characteristic steel material, which would lead to further investigation of specimens in the prestressed state. For the experimental part of the research, a system was set up for saturating the samples with hydrogen, which diffuses into the steel structure in atomic form. These specimens were then subjected to tensile testing according to EN ISO 15630-3 to reveal the reduced mechanical properties of the prestressed concrete steel strand specimen caused by the diffusion of hydrogen into the material structure. After the tensile tests, the fracture surfaces were analysed on a scanning electron microscope to verify the effect of hydrogen.