Yushchuk O. Load-bearing capacity, crack resistance and deformability of reinforced concrete continuous beams under the action of low-cycle repeated and alternating loads

The dissertation is devoted to the study of the stress - strain state, crack resistance and deformability of reinforced concrete continuous beams under the action of low-cycle repeated and alternating loads. The analysis of the obtained results of experimental tests showed decreasing of the load-bearing capacity of reinforced concrete beams affected by low-cycle repeated and alternating loading in comparison with beams loaded with a static load until fracture. However, the following feature of the beams operation was noticed: under the action of repeated loads according to the loads level, the processes of cracking and deflections are stabilized, while under the action of alternating loads, there is a constant increase of deformation, up to fracture. This occurs due to the formation of main cracks, cutting the entire cross-section and changing the bending stiffness properties of the normal cross-section.