Evaluation of Steel Targets

DOE-STD-3014-96

(where f/c = ultimate compressive strength of concrete in psi)

at the perimeter, one-half the effective depth away from the

load. This criterion is very conservative compared to recent

test results, but may be used conservatively for structural

screening purposes and for cases where punching shear is

not likely to be critical. For marginal or critical cases, the

alternative formula in Appendix C of this standard can be used

as applicable. For punching shear evaluation, the dynamic

increase factor, strength reduction factor, and ultimate load

factors are given in Appendix C of ACI 349.

Evaluation of Steel Targets. A widely accepted formula for predicting

6.3.2.2

penetration of steel targets is the Ballistic Research Laboratory (BRL)

formula:

0.5MV 2

1.5

(6-3)

1.5

17,400KsD

where:

predicted thickness to just perforate a steel plate

(in.);

W/g missile mass (lb-sec2/ft);

missile impact velocity (ft/sec);

constant depending on the grade of steel

1);

(usually

missile diameter (in.).

The range of test data parameters used in developing this formula and

their scope of applicability are not defined. However, the formula is

independent of target size or support conditions. It should be used only

to predict local perforation of steel structures by small rigid missiles. To

prevent perforation of steel targets, the minimum thickness, td, should be

> 1.25T.