Local Response Evaluation.

DOE-STD-3014-96

APPENDIX C

C.6.3.2

Scabbing Thickness.

C.6.3.2.1.1

Modified National Defense Research Committee (NDRC) Formula (1976)

(Reference 4).

In the local response sequence, the phenomenon of penetration is initiated by

spalling or chipping off of the concrete from the front face. Penetration is the

displacement of the missile into the target. The Modified NDRC formula predicts

the penetration depth, x, of an equivalent solid circular cylindrical missile:

1.8

4KNWD

1000D

(C 6-3)

for

< 2.0

1.8

KNW

1000D

(C 6-4)

for

> 2.0

where:

penetration depth of missile (in.);

concrete penetrability factor = [180/(f'c)];

ultimate compressive strength of concrete (lb/in.2);

f'c

C-6