Provision of openings in serviceable rein forced concrete beams may result in a
substantial decline in the beam’s capacity and integrity; pointing out the necessity of opening
strengthening. The present study investigates the response of reinforced concrete T-beams with
strengthened openings disposed in shear span. The experimental program consisted of four large-scale beam specimens. An opening in the web of 100-mm x 300-mm was centrally disposed in the
shear span. The strengthening of the openings was achieved using mild steel strips of 3.0-mm
thick or uni-directional CFRP fabrics. All specimens were tested as simple beams subjected to
two-points loading with a shear span to effective depth ratio of 1.7. The load was incrementally
applied following a specified displ acement history. Test results indicated that the strengthening of
openings may offset the anticipated decline in the beam capacity a nd stiffness due to the existence
of the openings. The extent of offset is dependent on the strengthening scheme adopted. The gain
in shear capacity of the tested beams ranged fro m 48% to 100%. In addition, a non-linear finite
element analysis; NLFEA was carried out to investigate the ultimate behavior of the beam
specimens. The application of NLFEA for the strength prediction of the tested beams yielded
adequate results. |
