UFC 4-171-05
1 January 2005
with change 25 October 2006
3-7.5
Wall Elevations
3-7.5.1 Structural wall elevations will be provided in the construction (drawings)
documents. Concrete masonry wall elevations will note the reinforcing steel, steel or
masonry lintels and other pertinent information. Wall elevations should \ reference
architectural and mechanical drawings for actual dimensions of wall openings./2/
3-7.5.2 Structural may consider a key plan (building footprint) for referencing wall
elevations.
3-7.6
Antiterrorism/Force Protection (AT/FP) Considerations
3-7.6.1 Refer to Section 2-5 of this document for AT/FP documentation and further
information. The USAR prefers that buildings be limited to two stories to avoid additional
construction costs necessitated by buildings over two stories in height.
3-7.6.2
A brief summary of some structural requirements:
3-7.6.2.1 For all multistory (three or more stories, not including the basement, if
applicable) inhabited structures, design all vertical load bearing elements assuming the
loss of lateral support at any one floor level. For design of vertical elements, the
effective length is established by lateral support by the roof or floor level(s). This will
essentially double the design effective length of the column, and thus possibly increase
its size. The design of the vertical element should include the load contribution from the
lost level. This requirement is independent of standoff distances.
3-7.6.2.2 Exterior masonry walls will be reinforced in all inhabited structures. Refer to
AT/FP criteria for minimum masonry reinforcing. When AT/FP standoff distances are not
met, grouting and vertical reinforcing may need to be increased to resist the damage of
an explosive placed at the standoff distance.
3-7.6.2.3 On multistory (three or more stories, not including the basement, if applicable)
inhabited structures, design all floors and roofs with improved capacity to withstand load
reversals. This requirement is independent of standoff distances.
3-7.6.2.4 AT/FP requirements restrict the use of load bearing concrete masonry and
load bearing steel stud walls for multistory structures (three stories or more, not
including the basement, if applicable). Exterior walls in multistory inhabited structures
will employ one-way wall elements spanning vertically to minimize blast loads on
columns. AT/FP requires that concrete masonry walls span vertically and be isolated
from vertical elements (i.e., columns) of the frame system. This requirement is
independent of standoff distances.
3-7.6.2.5 When portions of inhabited structures with lesser occupancies are located
within prescribed standoff distances, structurally separate those portions of lesser
occupancy from the remaining portions of the structure that meet the standoff distances.
Individual structural framing systems may be utilized, for example, locating two columns
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