Global Response Evaluation.

DOE-STD-3014-96

Alternative formulas such as the Stanford Research Institute (SRI)

formula and the Hagg-Sankey formula can be used as applicable.

6.3.3

The objective of the global response evaluation is to determine if the

impact of the aircraft results in the excessive deformation or collapse of

the target structure. A localized collapse evaluation (i.e., the collapse of

a segment, a component, or a portion of the structure) may be sufficient if

it can be demonstrated that such a localized collapse would not adversely

affect the structure's function or the function of any systems or

components. Global response evaluation of a building or a structure

typically involves characterization of the nonlinear behavior of both the

aircraft and the target, including soil-structure interaction.

Global response evaluation can be performed by either the energy-

balance method or the time-history analysis method. The energy-balance

method discussed in Section 6.3.3.1 can be used for global response or

collapse evaluation if the following conditions are met: (1) there are no

safety-related SSCs supported by the target in the vicinity of the impact;

(2) the configuration of the target is simple, such that the overall dynamic

characteristics of the structure can be adequately represented by a

single-degree-of-freedom (SDOF) nonlinear energy-absorbing system;

and (3) the resulting response of the SDOF system would be compatible

with the strength and ductility limits of the various components and

supports of the impacted structure. If these conditions are not met, then

the time-history analysis method described in Section 6.3.3.2, or in

Appendix C, Section C.6.3.3.2, should be used to evaluate the global

response.