RESULTS OF EXPERIMENTAL RESEARCH OF THE REINFORCED CONCRETE SHELL-SLAB

Abstract

Introducton. The paper demonstrates the results of experimental research of the reinforced concrete shell-slab under the action of vertical uniformly distributed load. The authors also present the comparison of such research results with the results of stress-strain state evaluation performed in the “Lira” software package.Materials and methods. The authors tested the reinforced concrete model representing physically similar copy with the 1:5 scale coefficients by general size, and by separate details. The load was applied in 10–15% doze of the theoretical bearing capacity of the plate.Results. The authors calculated the experimental transverse stress σх,3,exp, which was in full-scale construction and in the 3 central sphere. The authors also made the comparison of such transverse stress with theoretical transverse stresses σх,3,teor and the comparison was performed in the “Lira” program complex. The diagrams of the above stresses were well matched by outlines and values.Discussion and conclusions. As a result, the experimental (σx, 3,exp.) and theoretical (σx,3,theor.) stresses are compressive near the shell-slab center. Its maximum stress values (σx, 3, exp) reach x/b=0,5 at a point with a relative coordinate, and the stress (σx,3,theor.) – x/b ≈ 0,45.The zero voltage values σx,3,exp. reach a quarter of the shelf width, theoretical stress –with x/b ≈ 0,3 mm ratio.Maximum values of experimental and theoretical tensile stresses σx, 3 reach x/b ≈ 0,15 ratio. Therefore, the values are close to each other, and do not exceed the standard concrete tensile resistance Rbt, ser.The practical significance of the study is to obtain experimental evidence of the abandoning possibility of the horizontal transverse reinforcement of the shelf, which would reduce the complexity and cost of the investigated structures production.The prospects conclude in:research of the shell-slab operation at the stage of ultimate equilibrium;research of the shell-slab crack resistance and stiffness at all stages of its operation;research of the shell-slab operation taking into account the fixation in the transverse direction of its longitudinal contour edges along entire length.