Weld Joint Efficiency of the Kazakhstani Constructional Steel

In the Republic of Kazakhstan, the regulatory framework in construction based on Eurocodes has been in force since 2015. However, Kazakhstani produced steel has not been studied for compliance with the requirements of Eurocode 1993. This has resulted in limited use of Kazakhstani structural steel in construction. The feasibility of using structural steel in welded joints has been experimentally investigated. To verify the application of such joints in construction, including earthquake engineering, experimental studies of welded joints made of structural steel produced by Arcelor-Mittal in Temirtau have been carried out. In total, 7 types of structural steel of various thicknesses were selected. Five specimens have been used in each series of tests. The Brinell hardness values of the weld joint, yield strength of steel and tensile strength, relative rupture strain were determined. It was found that for all types of structural steel, the quality of weld joints complied with the requirements of Eurocode 1993—a sample rupture appeared along the plates (main body of the metal), not along the weld joints. It has been established that structural steel produced in the Republic of Kazakhstan fully complies with the requirements of Eurocode 1993. The studies on the dependence of Brinell hardness values of weld joint steel on the yield strength, tensile strength and relative rupture strain have been carried out. The correlation dependences between the values of yield strength of steel and tensile strength, relative rupture strain and BH Brinell hardness were studied. The results of work will allow for significantly increasing the use of Kazakhstani structural steel in seismic and conventional areas of the Republic of Kazakhstan.

Experimental Research of Impact Toughness of the Kazakhstani Construction Steel— Assessment of Compliance with the Provisions of 1993 Eurocode

Since 2015, the Republic of Kazakhstan has a new regulatory framework for construction on the basis of Eurocode. Many new steel quality requirements have been introduced for steel structures. As a result, Kazakhstan’s steel production almost ceased to be used in construction. Therefore, a series of studies is being carried out to determine the quality of local steel for compliance with the requirements of Eurocode 1993. Impact toughness testing was carried out on 126 samples of 8, 10, 20 mm thick structural steel produced by the “Arcelor-Mittal” company. The experimental study of impact toughness of KCV and KCU at a temperature of +20˚, -20˚, -40˚ degrees were conducted for seven types of structural steel, the most common in the Republic of Kazakhstan, on the experimental experimentation facility of the KazRDICA JSC. The ST RK STB EN 10045-1-2012 techniques were used. In each series of tests, 3 specimens were used. It has been established that in all cases the temperature requirements of Eurocode 1993 (National Annex to SP RK EN1993-1-1: 2005/2011*, Table НП.2*) are met. A regression relationship between the values of impact toughness and temperature was constructed. It has been established that construction steel produced in the Republic of Kazakhstan fully complies with the requirements of 1993 Eurocode. The studies on the dependence of Brinell hardness of steel on the impact toughness of steel at specified temperatures are performed. The correlation dependencies between the values of impact toughness and BH Brinell hardness have been obtained.