Structural Evaluation Criteria.

DOE-STD-3014-96

When necessary data for the given aircraft are not available, an

approximate method given in Appendix C may be used to determine F(t),

by scaling available impact force time-histories of other similar aircraft

(see Reference 1).

The second step is to develop a structural model of the impacted

structure and perform a dynamic analysis using the impact force time-

history computed in the first step or the one obtained from Reference 1.

Structural Evaluation Criteria. Deformation responses computed for

6.3.3.3

various target structural components by either the energy-balance

method or the time-history analysis method are then used to compute the

ductility ratio (the ratio of computed displacement to elastic

displacement). Computed ductility ratios are then compared to the

permissible ductility ratios specified below to determine if the component

would deform excessively or collapse under impact loads.

a. For concrete structural components, the permissible ductility ratios

shall be as specified in ACI Code 349, Appendix C, Section C-3. For

beam columns, walls, and slabs carrying axial compression loads, the

provisions of Paragraph C 3-8 of ACI Code 349, Appendix C, shall be

followed.

b. For steel structural components, the permissible ductility ratios shall

be as specified in Section Q1.5.8 of AISC Nuclear Specifications,

ANSI-N690 (Reference 11). For plate structures, the permissible

ductility ratio of 10 is recommended.

Potential loss of SSC safety functions resulting from structural

deformation and degradation due to aircraft impact should also be

evaluated.