Assessment of Durability of Metal Constructions of Industrial Buildings with Taking into Account Corrosion-Related Degradation of Mechanical Properties of Steel

Abstract

It is shown that in case of assessment of durability of metal constructions of industrial buildings it is neces- sary to consider a factor of decrease of mechanical properties of steel under the influence of a hostile envi- ronment (corrosion). The results of long-term corrosion and mechanical testing of steels 09G2S and VSt3sp5 in the range of climatic temperatures are presented. The samples were exposed in the operational middle aggressive environment of enrichment plant concentrating shop of diamond-mining industry. It is revealed that in case of –60 °C and a term of exhibiting of 2,5 years the decrease in mechanical properties for steels VSt3sp5 and 09G2S reaches accordingly the following values: 13.6 and 13% by a fluidity limit; 9.0 and 11% by a temporary resistance; 19.3 and 15.3% by a relative lengthening. Special attention in the article is paid to the mechanism of the processes causing such results. A technique of assessment of durability of a metal- works which consists in determination of a moment after which a reduction of the sizes of cross sections and fall of durability of construction steels lead to exhaustion of the bearing capability of constructions is offered. The results of calculations of constructions durability confirming applicability of the developed methodical approach are provided.