| Summary: | Flexural strengthening of reinforced concrete (r.c.) beam is now becoming more and more important in the field of structural maintenance and retrofitting. Plate bonding methods using steel plates are very widely used in this field. However, premature debonding at plate ends i.e. end peelings have been a major concern in using these methods. Researchers in general concluded that shear and normal stress concentrations at the plate cut-off point are the main reasons causing end peeling. For minimizing these stresses to prevent end peeling, end anchoring using U and L shape metal plates is proposed in this paper. This paper presents the results of experimental studies carried out to investigate the effect of U and L shaped end anchors on steel plate strengthened reinforced concrete beams. A total of four beam were cast. One beam was left un-strengthened as the control; the remainder three beams were strengthened with steel plates. From the strengthened beams, one was simply strengthened without end anchors and two were end anchored using U and L shaped anchor plates respectively. The results indicate that, all strengthened beams exhibited higher failure and cracking loads with less strain, deflection and crack width and better crack patterns than the control beam. It is also indicate that the strengthened beams with end anchors recorded the highest failure loads and their modes of failure were seen to be more ductile compared to the un-anchored strengthened beam. Results also shows that premature end peeling was completely prevented by U and L shaped anchor plates. In comparison, the L shaped end-anchor gave better performance compared to the U shape end anchor.
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