An analytical
procedure to determine the need for concrete confinement at the boundaries of
the RC structural walls subjected to earthquake load is presented by relating
the displacement demand of the building system to the local deformation in the
wall cross section. The primary variables used to determine the need for
confinement are the ratio of wall cross sectional area, the wall axial load and
the wall reinforcement ratio. The validity of the analytical approach is
demonstrated by evaluating two existing buildings in Bangladesh and also by
comparison with the experimental study of a two-third scale shear wall
conducted in this study. The proposed approach can be used for evaluation of
existing shear wall buildings as well as to verify current force-based
procedure to determine the need for confinement of shear wall in Bangladesh.
Parallel to the
evaluation of need for confinement at the boundaries of shear wall,
experimental study has also been performed to evaluate the effectiveness of
using externally bonded carbon fiber sheet (CFS) to increase the confinement of
boundary elements of RC shear wall. The experimental program comprises three
two-third scale wall panels representing the control wall and two
CFS-retrofitted wall panel using two different retrofit schemes. Based on the
procedure in ACI 440.2R-08 for strengthening RC structures by externally bonded
FRP systems, an analytical procedure for retrofit design of shear wall to
improve ductility, has been presented and verified by the experimental results.