Advances in Seismic Design Methodologies - Earthquake Engineering for Structural Design - page 445

Advances in Seismic Design Methodologies 445

Figure 9.39 Short columns produced by partial infillsd masonry (FEMA 389, 2004)

Effects of non-structural components to structure. There are notable cases of
structural and non-structural interaction, that has been the cause of structural damage
leading to collapse. These cases involves rigid, strong architectural components, like
masonry infill or concrete walls, which inhibit the movement or distortion of the
structural framing and cause premature failure of columns or beams. The short column
resulting from a partial infilled masonry (Fig. 9.39) are especially very dangerous,
producing the column collapses due to shear forces.
Pounding or movement effects. Another source of non-structural damage involves
pounding or movement between adjacent buildings across the separation joints. A
separation joint is the distance between two different buildings which allows the
structures to move independently of each other. In order to provide functional
continuity between separate buildings, the utilities must often extend across these
building separations (Fig. 9.40). Flashing, piping, fire sprinkler lines and all equipment
services have to be detailed to accommodate the seismic movements expected at these
locations, when the two structures move closer together or further apart. In case such
details are not adequately solved, the danger of fire after an earthquake significantly
increases, due to the fracture of gas pipes. Damage to items crossing seismic gaps is a
common type of earthquake damage. If the size of the gap is insufficient, pounding
between adjacent structures may produce damage to structural components, such as
parapets or cornices.