Research of monolithic cross-ribbed concrete slabs with of the office-commercial-entertainment complex building in Kyiv

Анотація

The structural elements of the ceiling are simulated in the form of a continuous slab-beam system, which, in calculations, is replaced by a discrete physical cross-link rod with a statically indefinite model. The longitudinal and transverse elements of the ceiling structure represent the geometric axes of the cross beams, whose stiffness in a static pattern corresponds to their actual stiffness. The equation of the static equilibrium of the node of the cross-ribbed system, expressed through knot bending moments and the external load and the equation of indissolubility of deformations, is a system of finite linear algebraic equations that is sufficient to determine unknown bending moments and vertical moving of the elastic bent axis of the beam in each given node. The conducted theoretical studies have made it possible to determine the magnitude of effort in the elements of cross-ribbed ceiling before and after reconstruction. To develop measures to strengthen the monolithic ceiling, there are two stages of calculations: the finding of the residual stresses in the reinforcement and concrete in time of the survey of a set of concrete strength; finding necessary sizes of areas of additional reinforcement for the performance of reinforcement.  When solving the engineering problem for the perception of additional bending moments and transverse forces, the use of additional carbon composite reinforcement in the form of tapes glued in zones of maximal tension on the surface of structures as additional external reinforcement is proposed.