Prototype Model for Simulating Barrier Fire Performance: CFAST.GYPST - For Evaluating the Thermal Response of Gypsum-Panel/Steel-Stud Wall Systems.
Prototype Model for Simulating Barrier Fire Performance:
CFAST.GYPST - For Evaluating the Thermal Response of
Gypsum-Panel/Steel-Stud Wall Systems.
Cooper, L. Y.; Reneke, P. A.
NISTIR 6482; 70 p. February 2000.
Available from: National Technical Information Service
(NTIS), Technology Administration, U.S. Department of
Commerce, Springfield, VA 22161.
1-800-553-6847 or 703-605-6000;
Order number: PB2000-104793
predictive models; algorithms; ASTM E119; compartment
fires; fire barriers; fire models; gypsum board; steel
studs; walls; zone models
Zone-model-type simulations of compartment fire
environments, which include the thermal response of
barrier/partition structural elements, are discussed in
the context of the adequacy of using a one vs
multi-dimensional heat transfer analyses for the
barriers/partitions. Introductory discussion focuses on
the identification of barrier/partition designs and fire
scenarios where such a one-dimensional analysis is valid
even when a two- or three-dimensional analysis would be
required to study the thermal-structural response. The
ideas presented are implemented in a prototype model,
CFAST.GYPST, an advanced version of CFAST, which uses
the algorithm and associated FORTRAN subroutine GYPST,
developed previously to simulate the thermal response of
fire-environment-exposed wall systems constructed of
arbitrary-thickness gypsum panels mounted on either side
of vertical steel studs. GYPST was designed as a modular
algorithm/subroutine for integration into zone-type
compartment fire models and for use in "stand-alone"
analyses. CFAST.GYPST is validated by using previously
acquired experimental data from ASTM E119 furnace tests
of two different, full-scale wall-system designs. This
is accomplished by first establishing a particular room
fire scenario where the simulated room fire environment
closely follows the ASTM E119 furnace environment. It is
then verified that, when the upper layer gases are
opaque (analogous to a typical wall furnace exposure)
and closely track the ASTM El19 temperature-time curve,
the CFAST.GYPST-simulated thermal wall-system response
compares favorably to the corresponding experimental
thermal-response data acquired during the
furnace-exposed wall-system tests. In example
"real-fire-type" simulations that are relatively-severe
(i.e., the upper layer temperature rises above that of
the ASTM E119 standard fire for several minutes and then
drops below it), CFAST.GYPST is used to calculate the
fire environment and associated wall response for each
of the above-referenced wall systems for a room geometry
and fire energy-release history that is related to that
of a newly developing ASTM room fire test standard. For
these simulations, the thermal responses of the two wall
systems are predicted and then evaluated relative to
respective expected fiie resistance.