Ensuring the Safety of Reinforced Concrete Beams along the Oblique Sectionunder Repeated Loads
The actuality of the problem of fatigue resistance of reinforced concrete structures along the oblique section under the action of repeated loads is substantiated.There are no recommendations for setting the criteria of fatigue rupture of reinforced concrete structures in SP 63.13330.2012 «Concrete and ReinforcedConcrete Structures. Main provisions» The revised edition of SNiP 52-01-2003; they don’t regulate the methods for calculation of the stress state under repeatedloads and the limits of materials durability. The article formulates recommendations on the development of new techniques and methods for fatigue strengthcalculation of reinforced concrete structures. Under repeated loads, the intensification of the concrete creep takes place that leads to the increase in residualdeformations of the compressive zone of the concrete. As a result of development of vibro-creep of the concrete under constrained conditions in the processof cyclic loading, the continuous change in the stress-strain state, coefficients of the asymmetry of the stress cycle and fatigue endurance of concrete andreinforcement occur. In such conditions the most rational is to assess the states of structures under repeated loads via the test of endurance conditions.