(Nicholas, 1990) Making joint systems fire-resistive was addressed
in a 1991 article. (Nicholas, 1991-1) Due to industry confusion
between fire-resistive joint systems and firestop systems, another
1991 article compared and demonstrated that there are many
differences, including designing for expansion/contraction and shear
movements at joints within a building (Nicholas, 1991-2), between
fire-resistive joint systems and firestop systems tested to ASTM
E814 (ASTM International, 2017-1).
These articles about joint movement resulted in a new standard
test method being published to determine Cyclic Movement and
Measuring the Minimum and Maximum Joint Widths of Architectural
Joint Systems under ASTM E1399. (ASTM International, 2017-2)
ASTM E1399 is the basis of the cyclic movement requirements
in the fire-resistive joint systems standards ASTM E1966 (ASTM
International, 2015-2) and ASTM E2307 (ASTM International, 2015-1)
as well as ASTM E2837 (ASTM International, 2017-3). ASTM E2307
specifically addresses the unique conditions of a perimeter joint,
including movement. It was realized that deflecting the transom(s)
when the adjacent mullions are anchored to the floor assembly was
impractical in a fire laboratory environment. Adopting the cyclic
movement principles and the testing methodology in ASTM E1399
was practical and potentially a more onerous test condition.
To be considered a dynamic perimeter joint protection, both
expansion/ contraction and shear movements must be cyclic tested.
The cyclic movement demonstrates the perimeter joint protection’s
ability to move in expansion/contraction responding to environmental
forces (wind, thermal, and seismic) and to move in shear in reacting
to live loads while maintaining a seal between the floor assembly
and exterior wall assembly and resisting fatigue and degradation.
The cyclic rate, magnitude, and duration of movement can also affect
the performance of the perimeter joint protection when subjected to
standardized fire exposure. ASTM E2307 provides test conditions
for these variables.
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