Civil Engineering Reference
In-Depth Information
Chapter 16
Special Cases
Abstract
Special cases like engine impacts, the effects of flying wreckage or small
aircraft and debris have to be considered in the design. Jet fuel fire may also cause
damage and must be regarded.
16.1 Engine Impact
The impact of an individual jet engine as a side effect of an airplane crash represents
a special case and must be considered separately. However, the effect of the
impacting engine is already an integral part of the respective impact load-time
function of a specified aircraft and is therefore included in the calculations of
the local and structural behaviour.
In addition to the local and global structural behaviour due to an aircraft impact
the question must be asked whether an engine can penetrate the reinforced concrete
shell of the reactor building locally. Aspects such as vibrations do not play a role in
connection to this. The topic of the possibility of perforation has already been
extensively examined by a variety of sources in the past (cf. e.g. [
1
-
5
]), in large part
using information gained from military expertise.
A turbojet engine of the type GE-J79 built by General Electric (cf. Fig.
16.1
)is
installed in the Phantom and many other military aircraft. Within the framework of
the experiments carried out at Sandia the effects of this engine were analyzed in
detail. For example an impact load-time function as shown in Fig.
16.2
was
developed. In addition appropriate perforation formulas were tested and evaluated.
Figure
16.3
for example shows the results of the necessary penetration thickness
that the author has compiled in conjunction with other projects. The results of the
examinations show that a 1.80 m thick steel reinforced concrete wall cannot be
penetrated by an engine.
