Experimental behaviour of optimized hybrid coupled shear walls

This paper shows the experimental structural behaviour of an optimized solution for hybrid coupled shear walls, which are seismic‐resistant systems composed of a reinforced concrete wall, with two side steel columns connected by beams ‐ the dissipative element. The optimized solution is proposed to upgrade the global behaviour of the system, with the aim of reducing the bending moment at the base of the reinforced concrete wall. Indeed, previous experimental tests demonstrated that the wall may suffer from early cracking at the base, despite the possibility of controlling the base bending moment thanks to properly balancing stiffness and resistance of the different components of the system. The optimized solution is numerically developed and designed with the philosophy of redistributing bending at the base of the wall by removing the lateral portions of the concrete and replacing them with a couple of steel hinged profiles, to control the deformations and absorb the torque. The central concrete part of the wall is kept but reduced to the minimum, to transfer the shear, only, reaching closely hinged‐like conditions. Two different solutions are proposed for the central reduced part of the wall: in the first case, the cross section is gradually reduced to the base, while in the second one, the wall is connected through a steel pin to the base. Both solutions are tested under monotonic load for a preliminary assessment of the actual benefits at the base of the wall compared to the original proposal.