Civil Engineering Reference
In-Depth Information
L
L
1. CANTILEVER COLUMN
2. UNBRACED FRAME
3. BRACED FRAME
WALL
WALL
L
L
5. STRUCTURAL WALL
4. INFILLED FRAME
6. STRUCTURAL CORE
Figure A.13
Basic structural systems with increasing lateral stiffness (
from top left to bottom right
)
depends primarily on the detailing of the foundation connection and their shape. Walls can be arranged
to form rigid core systems. The latter possess high resistance but, as for structural walls, their inelastic
behaviour can be impaired by seismic details with low ductility.
Basic elements shown in Figure A.13 are used for vertical systems of buildings and bridges. Typical
lateral load-resisting systems include the following:
(i)
Moment - Resisting Frames
(ii)
Braced Frames
(iii)
Structural Walls
(iv)
Hybrid Systems
(v)
Tube Systems
Moment-resisting frames can dissipate a large amount of energy, but they often suffer from large
lateral displacements. Conversely, braced frames possess high lateral stiffness but relatively low defor-
mation capacity. Hybrid and tube systems generally exhibit adequate structural performance. The
seismic response characteristics of the above structural systems under horizontal forces are discussed
below.
(i) Moment - Resisting Frames
Moment-resisting frames (MRFs) are structural systems consisting of beams, columns and joints. These
systems are frequently used as structural skeletons in RC, steel and composite buildings and bridges.
