Efficiency of CFRP strips as a substitute for carbon steel stirrups in RC columns
- PDF / 1,276,906 Bytes
- 12 Pages / 547.087 x 737.008 pts Page_size
- 69 Downloads / 219 Views
(0123456789().,-volV) (0123456789().,-volV)
ORIGINAL ARTICLE
Efficiency of CFRP strips as a substitute for carbon steel stirrups in RC columns Nur Hajarul Falahi Abdul Halim
. Sophia C. Alih . Mohammadreza Vafaei
Received: 14 May 2020 / Accepted: 30 September 2020 Ó RILEM 2020
Abstract It has been shown that the corrosion of the reinforcing bar can significantly affect the strength and ductility of concrete structures. This study proposed the use of CFRP strips as a substitute for carbon steel stirrups in RC columns to decrease the effects of corrosion. An experimental program comprising of four columns was employed to investigate the cyclic response of RC columns transversely reinforced by CFRP strips. All columns had similar material properties and reinforcement ratios, but their transverse reinforcements were different. The obtained results showed that the RC columns transversely reinforced by CFRP strips had a larger ultimate load and effective yield strength when compared with the reference column that was transversely reinforced by carbon steel. Besides, the stiffness degradation rate of CFRP confined columns was slower, and they were able to dissipate more energy when compared with the reference column. The columns confined with CFRP strips also exhibited a slightly larger displacement ductility ratio.
N. H. F. Abdul Halim M. Vafaei (&) Faculty of Engineering, School of Civil Engineering, Universiti Teknologi Malaysia, Skudai, Malaysia e-mail: [email protected] S. C. Alih School of Civil Engineering, Institute of Noise and Vibration, Universiti Teknologi Malaysia, Skudai, Malaysia
Keywords RC column Transverse reinforcement CFRP Quasi-static cyclic load Stirrup
1 Introduction The corrosion of reinforcing bar in concrete structures has a significant impact on their serviceability and integrity. An experimental study on the partially corroded reinforced concrete piers showed that 15.82% rebar mass loss decreased the ultimate load and ductility ratio of axially loaded columns by 29.96% and 9.26%, respectively [1]. Corrosion also can decrease the ultimate load of the precast concrete floor and can result in bond degradation and loss of effective restressing force [2]. It has been shown that corrosion can alter the failure mode of reinforced concrete structures and decrease their seismic capacity [3]. Some studies suggest that the effects of corrosion should be taken into account when evaluating the seismic fragility of RC bridge in marine environments [4]. Results of shake table tests on corroded concrete columns revealed that a 51% area loss ratio decreased the residual strength of columns by 80% [5]. Corrosion of reinforcing bar can significantly increase the probability of moderate to severe damage in chimneys when they are subjected to ground motions [6]. Experimental tests on scaled-down RC columns with a low level of corrosion indicated that the
129
Page 2 of 12
displacement ductility was significantly reduced [7]. It has been shown that, under seismic actions, a wellconstructed RC column
Data Loading...
