Performance properties of modern reinforcing bars

Introduction. In the modern world, where the main emphasis in construction is placed on the safety of human life, in our country we still produce and use steel reinforcing bars that are capable of brittle fracture under negative circumstances due to their high carbon content. In European countries the carbon content is limited to 0.22 % in all non-tensioned rebar at the end of the last century, in our country carbon content up to 0.29 % is allowed. Today’s building regulations allow the use of such high-carbon reinforcing bars even in structures that may be subject to special adverse environmental influences.

Aim. To highlight the problem of the potential brittle fracture of steel reinforcement produced in accordance with existing standards, with the possibility of its use in the construction industry in accordance with Russian codes of practice, including in special operating conditions and in responsible buildings and structures.

Materials and methods. For the experiment, A500C and A400 classes reinforcing bars made of 3Gsp and 25G2S grades steel respectively were used. The properties of the reinforcement and its welded joints were studied using standardised and specialized methods, including tensile, bending and impact tests at temperatures ranging from +20 to -60 °С.

Results. Experimental data characterizing the performance properties of rolled reinforcement bars of different classes were obtained, confirming the possibility of brittle failure of working reinforcement bars manufactured in the Russian Federation and used in accordance with requirements of codes of practice.

Conclusions. The conducted research allows us to see how a reinforcement bars that at first glance are good in terms of plastic properties, can radically change the perception of the quality and safety of its use when evaluating its operational properties.

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