SHEAR STRENGTHENING OF REINFORCED CONCRETE BEAMS USING SHALLOW-ANGLE CFRP LAMINATE STRIPS

This paper presents the experiment work to investigate the shear behaviour of RC beams
strengthened with externally bonded shallow-angle CFRP laminate strips. Four RC beams
with varies inclination of CFRP strips were used; namely 90, 45 and 25-deg. The results of
the test shown that shallow-angle of CFRP strips gave superb performance in term of shear
strength and deformation behaviour, compared with other conventional strengthening
scheme. An optimised truss model, based on the principle of minimum strain energy
theorem, was developed and used to predict the shear capacity of the CFRP strengthened
beams. It is shown that the proposed model can predict reasonably well to the test results
with coefficient of variation (C.O.V) of only 3.11%. Compared to other shear model/method,
the proposed model gave a better representative to the actual stress fields and behaviour.