Flexural retrofitting of the damaged reinforced concrete beams by using HPFRCC

Document Type : Article

Authors

Faculty of Civil Engineering, Semnan University, Semnan, Iran

Abstract

Damaged structures are not usually reliable to tolerate designed loads and therefor, need to retrofit in structural parts. The main purpose of this paper is to utilize HPFRCC as a high-performance material to recover the damaged beams and improve their ductility and moment capacity with experimental approaches. In addition to, a retrofitting method is presented using high-performance fibre reinforced cement-based composite (HPFRCC). The experimental study is performed on three simply supported beams with the same dimension, materials, and reinforcement configuration. The first beam, which is known as the reference beam (RC), is subjected to pure bending condition till its failure and the others are prone to a certain amount of load according to the final capacity of the first beam. Thereafter, two damaged beams are retrofitted using HPFRCC in the created grooves on tensile surface of the beam and finally these retrofitted beams are loaded to determine the bending behaviour. Experimental Results demonstrate that retrofitting can improve the first crack strength, load at yield condition, and maximum load capacity. Also, the proposed method increases the ductility and energy absorption of retrofitted beams.

Keywords


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