A Rehabilitation Experimental Program on Low-Strength Concrete with Steel Bar Planting

Document Type : Regular Paper


1 Department of Civil Engineering, Shahid Rajaee Teacher Training University, Lavizan, Tehran, Iran

2 M.Sc. Graduated, Department of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran


Many concrete structures need rehabilitation during their service life for different reasons; poor quality of construction, relatively lower compressive strength of concrete, non-compliance with existing or updated design codes, and buildings that experienced an intensive earthquake are to name but a few. One of the solutions to strengthen concrete structures is to install rebar inside the structural components. In this paper, the effect of steel rebar planting with a constant nominal diameter of 8 mm along with two different lengths (i.e., 35 and 55 mm) as well as two different planting angles (i.e., 0 and 45 degrees) have considered as variables. Therefore, the rebar planting process has conducted on 12 low-strength cylindrical concrete specimens with an initial compressive strength of 15.5 MPa. The concrete column specimens were tested under uniaxial compressive load after rebar planting. The results of this study indicated that rebar planting leads to an increase in the initial compressive strength of the concrete specimens in general. The specimens with 35 mm and 55 mm planted length witnessed an average enhancement of 17% and 23%, respectively. Moreover, considering the angle of planted rebar as another variable parameter, the obtained results revealed that the maximum compressive load for both 35 mm and 55 mm specimens with a planting angle of 0-degree and 45-degree almost followed the same increase and improved by an average of 5%.


Main Subjects

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