Experimental Investigation of RC Beams Retrofitted with Externally Bonded SIMCON Laminates.

The paper presents the results of experimental and analytical studies concerning the flexural strengthening of RC beams using externally bonded Slurry Infiltrated Mat CONcrete (SIMCON) laminates. The preliminary study of SIMCON laminates was carried out for optimizing the volume fraction (V_f ) and aspect ratio (l/d) of fiber mat. A total of 45 number of laminates of size 125×25×500 mm with different volume fractions (V_f = 4.0%, 4.5%, 5.0%, 5.5% and 6.0%) and different aspect ratios (l/d = 300, 400 and 300 and 400) were cast and tested in the laboratory. A total of five reinforced concrete beams were cast and tested in the laboratory over an effective span of 3,000 mm. Three beams were strengthened with bonded SIMCON laminate at the bottom under virgin condition and tested until failure; the remaining two beams were used as baseline specimens. Static responses of all the beams were evaluated in terms of strength, stiffness, ductility ratio, energy absorption capacity factor, compositeness between laminate and concrete and the associated failure modes. The theoretical moment-curvature relationship for the test specimen and the load-displacement response of the strengthened beams and unstrengthened beams were predicted by using FEA software ANSYS. Comparisons were made between the numerical (ANSYS) and the experimental results. The results showed that the strengthened beams exhibited increased flexural strength, enhanced flexural stiffness and composite action until failure. [ABSTRACT FROM AUTHOR]