Experimental and DIC Study of Reinforced Concrete Beams Strengthened by Basalt and Carbon Textile Reinforced Mortars in Flexure

Abstract

This paper presents an experimental study to strengthen flexure-deficient reinforced concrete beams using textile-reinforced mortars (TRMs). A set of seven reinforced concrete beams were strengthened using basalt and carbon TRMs. The current study utilised textiles with almost similar physical properties to strengthen reinforced concrete (RC) beams. All the studied beams were strengthened at their soffit to evaluate the effectiveness of textile fibres, the number of layers and the strengthening configuration. The experimental results showed that beams strengthened using carbon and basalt textile-reinforced mortar performed equally better in terms of overall performance with inherent textile slippage after the peak load. The flexural load capacities of the beams were strengthened with one layer, and three layers were higher when compared to the control beam. For the basalt TRM one, three and five layers registered an increment of 8.3%, 20.7% and 30.3% of ultimate strengths over the unstrengthened specimen. Similarly, for the carbon TRM one, three and five layers recorded an increment of 14.2%, 15.3% and 32.3% of ultimate strengths over the control specimen. Five-layered specimens with end U-wraps successfully mitigated premature debonding, along with registering maximum load capacity, and digital image correlation (DIC) was performed to monitor real-time crack width, crack patterns and spacing and to compare the load and displacement responses from all the tested specimens.