Abstract:
Performance of a structure in an earthquake is governed by its capacity to dissipate
energy. In mid- to high-rise buildings, coupled shear walls act as efficient lateral load
resisting and energy dissipation. Coupling beams, in coupled shear walls are designed to
yield prior to yielding of walls. This provides higher energy dissipation capacity to
coupled shear wall system as compared to uncoupled shear walls. Thus, the performance
of coupled shear wall system is dependent on the energy dissipation capacity and
ductility of the coupling beams. Various researchers have proposed different types and
design of coupling beams, such as RC, steel, composite beams. Recently different types
of fuses in coupling beams have been used and such systems are termed as Hybrid
Coupled Wall systems. The use of steel as coupling beam provides high degree of
ductility, acts as good energy dissipation system and has the added advantage of ease of
construction compared to diagonally reinforced beam. Fuses in coupling beams are
energy dissipation devices which have similar advantages as those of steel beam and can
be replaced easily. Literature on different coupling beams consists with experimental
evaluation of performance but little emphasis is there on use of beams in design to take
advantage of higher dissipation capacities.
The scope of this work consists in numerical modeling and design of a typical 15
storey building with coupled shear wall system, using guidelines of ACI 318, Euro-code
8, IS code and other available literature on design of Hybrid Coupled Wall systems.
Design recommendations for coupling beams are reviewed such that they yield well
before the walls yield. Design considerations for ductile performance of walls in
coupled system is also reviewed. Placement of shear walls of different sizes and various
locations is carried out and associated difficulties are discussed. The performance of
building with different types of coupling beams is evaluated using nonlinear static
procedures as per ASCE 41. From this study, it is observed that the Steel coupling
beams with fuses display the maximum ductility as compared to other systems. The
diagonally reinforced coupling beam displayed higher overstrength capacity. Model
with steel beams showed less ductility compared to other models due to formation of
flexural hinges which have less ductility compared to shear hinges
