Theoretical calculation method for crack resistance of jacketed RC columns

Abstract

Theoretical method of crack width calculation in jacketed reinforced concrete columns is described and validated in this paper. The total number of tested columns was 12. The initial load applied to the column before strengthening was the main variable parameter in this test. Columns were strengthened by reinforced concrete jacketing after loading. Two RC columns were tested without strengthening to serve as reference samples. Two RC columns were strengthened with RC jacketing without any initial loading to determine maximum strengthening effect. Loading was applied in steps. This study is the calculation of the crack resistance parameters RC columns, strengthened by RC jacketing under the influence of various initial loads. Crack width and pattern were checked after each step. The maximum allowed crack width for test samples was adopted as wmax = 0.3 mm. The rest eight samples were preliminarily loaded to 0.3; 0.5; 0.7 and 0.9 of reference columns bearing capacity, strengthened and tested to failure. The results of theoretical calculation deviate from test results by 13.6…27.9%.