The role of mutual shear deformations in ensuring the safety of prestressed reinforced concrete elements

Строительные конструкции, здания и сооружения

The object of study is prestressed reinforced concrete elements, with reinforcement tension on stops in the manufacturing and maintenance stages. It is noted that of all the significant parameters of bond - the stiffness of the contact of concrete with a prestressed reinforcing element can most reliably assess and ensure safe working conditions for the reinforced concrete element as a whole. Method. The determination of mutual shifts of reinforcement and concrete is carried out using the theory of built-up bars, adapted for prestressed reinforced concrete elements. A method for estimating mutual shear strains for elements with single and double prestressed reinforcement is presented. Recommendations are given for calculating the parameters of bond stiffness. Results. For a multi-hollow slab, the nature of the distribution of mutual shear deformations along the length of the structure for different stages of the life cycle is shown. It is proposed, when checking the strength of reinforced concrete elements with prestressed reinforcement, according to the deformation model, to additionally introduce a check of mutual shear deformations at the contact of concrete and reinforcement.