Analysis of Durability of Metal Structures under Random Impacts
Operation of welded metal structures involves the impact of cyclic and re-static loads on them. Strength and durability of such structures depend on initial defects. Random loads are one of the widespread types of loads acting on the structure. The main provisions of the theory of calculation of durability of steel structures elements under random impacts are presented. The methodology of calculation assessment of the durability of metal structures on the basis of the use of the probabilistic method for fatigue calculation of welded structures, when schematization of the loading process is performed, is proposed. The efficiency of the structure is ensured, if the cumulative fatigue damage in any given component during the design life at maximum permissible failure probability does not exceed the maximum value. The limit accumulated fatigue damage is calculated with due regard for the amplitude and number of loading cycles. The methodology presented was used for assessing the durability and endurance of operating metal crane girders according to to results of inspections and full scale tests.