Research of reinforced concrete elements strengthened by reinforced concrete jacketing under high level loading

Authors: 
Krayinskyy P. I., Yovchyk O. D., Vasiliev I. V. / Країнський П. І., Йовчик О. Д., Васільєв І. В.

Lviv Polytechnic National University,
Department of Building Constructions and Bridges

In this article the results of experimental study of reinforced concrete columns strengthened by reinforced concrete jacketing are produced. Reinforced concrete jacketing was chosen as the strengthening method since it is the most commonly used for reinforced columns repair and strengthening. The design of such strengthening will differ from basic column design methods since the impact of the load supported by the existing structure during strengthening should be taken into consideration. Determination of the impact of that factor is the main objective of this research. To achieve this reinforced concrete column specimens were manufactured and tested. Column specimens were strengthened after preliminary loading to different levels and then tested to failure as pinned columns subjected to eccentric loading. The columns were 2200 mm long, with cross section dimensions equal 180 mm by 140 mm. On both sides columns had cantilever sections to apply loading with 150 mm eccentricity. Four 12 mm rebars were used as longitudinal reinforcement (reinforcement percentage equaled 1,8 %). All specimens had identical geometrical and were manufactured from same materials. Eexperimental program included testing of control unstrengthened specimens along with strengthened under loading level that equaled 70 % and
90 % of control specimens ultimate strength.

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