INFLUENCE OF CONSTRUCTION’S LOADING LEVEL ON STRENGTH AND DEFORMABILITY OF RC COLUMNS STRENGTHENED BY CFRP

This paper presents results of research of reinforced concrete columns strengthened by CFRP laminate under different load levels. During the building exploitation it is often difficult to completely unload the structure, and in some cases impossible. To simulate this factor before strengthening experimental samples were adjusted to the level of 1/3 and 1/2 of experimentally determined destructive efforts of the unstrengthened column. For more experimental research dates two columns were strengthened without loading. All samples were strengthened by CFRP laminate Sika Carbodur S512 with 25 mm width. The loading was applied with eccentricity e = 150 mm. Comparative analysis was carried out and strengthened effectiveness was determined. The effectiveness of strengthening increases with decreasing loading level on construction but this difference was small during testing.

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