Summary: | The study deals with the investigation of the effect of casting deficiencies- both experimentally and analytically on axial yield load or reinforced concrete columns. It includes 6 specimens of square section (150x150x500 mm) of 24.37 MPa nominal concrete strength with 4 longitudinal steel bars of 8 mm (500 MPa nominal strength) with confinement ratio ωc=0.15. Through casting procedure the necessary provisions defined by International Standards were not applied strictly in order to create construction deficiencies. These deficiencies are quantified geometrically without the use of expensive and expertise non-destructive methods and their effect on the axial load capacity of the concrete columns is calibrated trough a novel and simplified prediction model extracted by an experimental and analytical investigation that included 6 specimens. It is concluded that: a) even with suitable repair, load reduction up to 22% is the outcome of the initial construction damage presence, b) the lower dispersion is noted for the section damage index proposed, c) extended damage alters the failure mode to brittle accompanied with longitudinal bars buckling, d) the proposed model presents more than satisfying results to the load capacity prediction of repaired columns.
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