expected compressed strength and then multiplying by not more than 1.15 to
account for a one year age effect.] [The expected yield stress for steel
sheet and strip used in design shall be computed as 1.21 times the
specified static yield point.]
1.3.1.2
Dynamic Material Strength
The dynamic material strength shall be computed by applying a dynamic
increase factor that accounts for the increase in material strength due to
strain rate effects. The dynamic increase factor for structural steel in
flexure shall be applied to the average yield strength and shall be [1.29]
[_____], [1.19] [_____], and [1.09] [_____] for structural steel having a
minimum yield strength (or yield point) of 248 MPa, 345 MPa, and 689 MPa,
36, 50, and 100 ksi, respectively. The dynamic increase factor for
structural steel having a minimum yield strength (or yield point) between
these values shall be obtained by interpolation. Optionally, for
structural steel in these yield ranges, the dynamic increase factor shall
be determined by a detailed analysis that accounts for the time to yield.
The dynamic increase factor for structural steel having a minimum yield
exceeding 689 MPa 100 ksi shall be 1.0. [The dynamic increase factor for
Grade 60 flexural reinforcing bars shall be [1.17] [_____] applied to the
average yield strength. The dynamic increase factor for concrete used in
flexure shall be [1.19] [_____] applied to the in-place compressive
strength. Optionally, the dynamic increase factor applied to flexural
reinforcing bar yield and concrete compressive strength shall be determined
by a detailed analysis that accounts for the time to steel yield and time
to ultimate concrete strength.] [The dynamic increase factor for steel
sheet and strip used in flexure shall be 1.1 applied to the average yield
stress.]
1.3.1.3
Structural Member Design
[Structural steel section properties for rolled shapes shall be obtained
from AISC 325, AISC 316, or steel manufacturers' catalogs. The plastic
moment capacity for single plate sections and sections built up from plates
and shapes shall be computed as the average of the elastic and plastic
section modulus multiplied by the dynamic yield strength, unless otherwise
approved. Shear, welds, local buckling, and web crippling of structural
steel shall be designed in accordance with AISC 325, the plastic design
provisions of AISC 335, or by other approved methods except that for blast
design, the load factors and resistance factors shall be equal to 1.0 and
the dynamic yield strength shall be substituted for the static yield
stress.] [Nominal reinforcing bar designations, weights, and dimensions
shall be obtained from ACI 318M/318RM ACI 318/318R or the reinforcing bar
specification. The moment of inertia of the reinforced concrete cross
section used to determine the elastic deflection shall be the average of
the moment of inertia of the gross section and the moment of inertia of the
cracked section. The resistance of the reinforced concrete section shall
be computed in accordance with ACI 318M/318RM ACI 318/318R or other
approved methods except that for blast design, the load and resistance
factors shall be equal to 1.0 and the dynamic reinforcing bar yield
strength and dynamic ultimate concrete strength shall be substituted for
the static strength values.] [Hollow metal doors shall be designed in
accordance with AISI SG-971-Spec except that for blast design, the dynamic
yield strength shall be substituted for the static yield point.]
1.3.1.4
Dynamic Analysis and Deformation
The door shall be designed using an equivalent single degree of freedom or
SECTION 08390
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