Application of steel

Coupled shear walls are widely used as the primary lateral load resisting element in high-rise buildings. But the coupling beams, which are often designed as deep members, usually suffer from brittle shear failure. The steel-concrete-steel sandwich deep beams showed high bearing capacity and great ductile performance during shear failure. Therefore, it is proposed that the steel-concrete-steel members can be used into deep coupling beams instead of conventional reinforced concrete members, to improve the shear strength and deformability. The shear failure of steel-concrete-steel deep beams is characterized by plastic yielding of the outer steel plates in the triangular areas, rather than concrete diagonal crushing. Reliable shear transfer paths are maintained by the interaction between the outer steel plates and the diagonal concrete struts, so excellent strength and ductile performance can be expected after critical diagonal cracking. The triangular failure areas are able to dissipate seismic energy, thus effectively avoiding overall collapse. The shear strength of steel-concrete-steel deep coupling beams is developed with simple expressions