Seismic Upgrading of Old Brick-Masonry Urban Houses: Tying of Walls with Steel Ties

The influence of tying the walls with steel ties on the seismic behavior of existing brick-masonry houses has been investigated. Three models of simple two-story brick masonry houses with wooden floors, with or without wall ties, have been tested on a simple earthquake simulator. In addition, a model with identical structural configuration, but with r.c. slabs instead of wooden floors, has been tested for comparison. Whereas wooden floors with joists not anchored to the walls did not prevent separation and disintegration of the walls, rigid slabs and steel ties significantly improved seismic behavior. On the basis of test results, a simple method for designing the ties has been proposed.