A number of aggressive substances influence reinforced concrete building structures’ decay and corrosion processes. In this research work the influence of steel reinforcement corrosion degree on its adhesion to concrete strength characteristics was determined. Two 14 mm diameter reinforcement steel types: ribbed (BSt500S) and smooth (A240C) were used in the work. The mass loss of steel reinforcement due to the corrosion was calculated. After the explosion in different solutions: 10% of NaCl, HCl and NH4NO3 the weight of steel reinforcement with smooth surface decreases for 1-8%, while the mass loss of ribbed reinforcement was 2-13% in comparison with control of steel reinforcement samples, which exposure in water. It was found that both smooth and ribbed steel reinforcement influenced by NH4NO3 solution corroded more intensively. The adhesion of this type of reinforcement (influenced by NH4NO3 solution) to the concrete was the lowest: the adhesion of smooth steel reinforcement decreased till 76% compared to the control concrete specimens adhesion and ribbed steel reinforcement was 92%. The unaffected steel reinforcement samples adhesion to concrete was the highest (46.33 kN and 59.875 kN, this is corresponds 100%).The potentiometric measurements showed that the most favorable probability of steel reinforcement corrosion to perform is when the steel reinforcement is exposed to NH4NO3 solution, potential difference is < -350 mV.
