Page 477 - Advanced Design Examples of Seismic Retrofit of Structures

420 Advanced Design Examples of Seismic Retrofit of Structures

TABLE 6.5 Summary of Results for Wall Pairs After GSAP Tests—cont’d

Model
No.
and Collapse Principal Retrofit
Walls Level Measures Comments
3NE No Bond beam, lower internal Stable behavior in all
collapse horizontal straps, and tests
vertical center-core rods
3SW No Bond beam, lower internal Stable behavior in all
collapse horizontal straps, and tests
vertical center-core rods
9 VI None (control model) Complete collapse of
gable-end walls
8NE No Partial wood Stable behavior in all
collapse diaphragms—upper strap tests
at attic-floor level, lower
straps, and vertical straps
8SW No Partial wood Stable behavior in all
collapse diaphragms—upper strap tests
at attic-floor level, lower
straps, and vertical center-
core rods; no lower strap
on west wall
7NE No Partial wood Stable behavior in all
collapse diaphragms—upper strap tests
at attic-floor level, lower
straps, and vertical straps
7 SW X Partial wood Partial collapse of south
diaphragms—upper strap (in-plane) wall during
at attic-floor level and test level X
lower straps; no vertical
straps

6.4.1.5 Comparison of Test Results and Field Observations
Comparison of laboratory tests and field observations of the Northridge earth-
quake show good correlation. The important observations can be summarized as
follows:
l Below 0.15g, little or no damage was observed in adobe buildings with good
conditions.
l Starting around 0.2g, minor and more severe cracks were observed in intact
buildings and previously damaged structures, respectively.