UFC 4-211-01N
25 October 2004
Including change 1, 1 October 2006
(OCBF) Ordinary Concentrically Braced Frames (Part 1, Sec 14)
(STMF) Special Truss Moment Frame (Part 1, Sec 12)
(IMF) Intermediate Moment Frame (Part 1, Sec 10)
(OMF) Ordinary Truss Moment Frame (Part 1, Sec 11)
4-4.4
Anti-Terrorism and Force Protection (ATFP). Consult UFC 4-
010-01 for the design loads as well as other analysis and detailing requirements.
4-5
DESIGN AND CONSTRUCTION DOCUMENTATION. Full
disclosure of the design loads and assumptions is imperative on all final design
drawings. This should include all loading conditions at all phases of the
structure's life, from skeleton erection through installation of finishes and
accessories (i.e., "dead load"). Loading conditions should also include absolute
and differential temperature effects in the stress and deflection information.
Drawing information should also include any anticipated shoring (methods and
points).
4-5.1
Thermal Loads. Account for anticipated differential thermal effects
from solar heating (e.g., on long sun-exposed exterior steel compared to shaded
steel such as roof trusses, joists or decking) or inside/outside differences
(particularly an "attic" effect in the hangar bay). Consider local climate conditions
when selecting the final differential temperature range, as a minimum, a
temperature differential of 28C (50F) should be used for design. Pay particular
attention to the deflections caused by thermal effects. Some architectural fascia
elements and weather seals around hangar doors are particularly vulnerable to
detrimental deflections. These thermal effects are a serviceability concern and
should be investigated using unfactored loads.
4-5.2
Additional Cantilever Requirements. The cantilever truss roof
design should incorporate a primary and secondary adjustment system to handle
dead load deflection. Ensure the facility design drawings include the following:
The Contractor must "level" the truss tips (above the hangar door)
after all roof and supported materials have been installed into their
final positions. It is suggested that the primary adjustment system
be installed in the forestay (and the backstay if necessary), but
other systems are permissible. To level the truss tips, the
Contractor must survey the roof truss system to ensure the
structural system is performing as the designer intended. The
Contractor's survey should be done during stable atmospheric
conditions (night, early morning, or a cloudy calm day). The
designer of record should review and approve the survey
information prior to installing the hangar doors. Primary
adjustments of more than 25 mm (1 inch) vertical movement, if
50
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