UFC 4-010-01
8 October 2003
Including change 1, 22 January 2007
B-3.1.1.4
Connection Design. The design of connections of window and skylight
frames to surrounding walls or roofs, of hardware and associated connections, of
glazing stop connections, and of other elements in shear will be based upon allowable
stress levels. The connection design load will be determined in accordance with ASTM
F 2248 based on the applicable explosive weight at the actual standoff distance at
which the window is sited, but not greater than the conventional construction standoff
distance. Additionally, the allowable fastener loads will be as recommended by the
fastener manufacturer for the materials to which the window or skylight systems are
being connected. Designers will account for the geometry of the particular frame and
the connection configuration being used when calculating bending, shear, bearing, and
pull out loads for the connections.
Note: The actual connection design load is dictated by the glass type and thickness
determined by ASTM E 1300. Therefore, in order to keep the connections loads
reasonable, use a glass type and thickness that just exceeds the required glazing
Connections must be capable of preventing the frame from being
dislodged from the supporting structural element. This may be demonstrated by
calculation as noted above or by testing. If testing is used, the type, number,
arrangement, and orientation of the fasteners must be the same in the test as in the
fielded application, including eccentricities between the glazing system frame and the
line of action of the connections. The structural supporting material used in the test for
fastener attachment will be representative of the fielded application. Any deviations in
field application of the connections or the connected elements from the test must be
demonstrated by calculation to provide equivalent support for the specific application.
B-3.1.2
Supporting Structural Elements. For window and skylight systems,
surrounding wall and roof elements and their connections to the rest of the structure
may be designed using their nominal strengths. For systems using laminated glass
glazing, the design load will be eight times the glazing resistance determined using
ASTM E 1300 in conjunction with ASTM F 2248 based on the applicable explosive
weight at the actual standoff distance at which the window is sited, but not greater than
the conventional construction standoff distance. This design load will be distributed to
the structural element only from the tributary area of the window.
It is not necessary to account for reactions from the supporting structural
elements in the design of the remainder of the structure, because the resulting dynamic
loads are likely to be dissipated through multiple mechanisms.
B-3.1.3
Alternate Glazings. Where glazing other than laminated glass is used,
design glazing, frames, and connections that will provide the applicable level of
protection as described above and in Tables 2-1 and 2-2 for the applicable explosive
weight in Table B-1. Refer to the DoD Security Engineering Facilities Design Manual for
further guidance. When window or skylight systems use glazing other than laminated
B-15
Previous Page
