Cyclic behavior of composite timber-masonry wall in quasi-dynamic conditions reinforced with superelastic damper

The cyclic behavior of a composite timber-masonry wall was evaluated in quasi-static conditions. The wall was conceived to replicate a traditional partition wall of the downtown area of Lisbon, rebuilt after the 1755 earthquake. The wall presented an almost linear behavior for small displacements, followed by a plastic deformation zone where significant inelastic behavior was observed. On a second stage, superelastic dampers based on the hysteretic behavior of NiTi wires were also installed to strengthen the wall. Good cyclic behavior was observed in these devices, although the difference in stiffness of the wall compared to the NiTi wires did not lead to significant increase in the overall area of the hysteresis of the force–displacement diagram. Nevertheless, the technique proved to be promising in reinforcing old building walls regarding their seismic behavior.