Civil Engineering Reference
In-Depth Information
Fig. 13.1
Cumulative frequency distribution (Summenh¨ufigkeit) of the mass m (Masse), the
impact speed v (Absturzgeschwindigkeit) and impact angle
(Absturzwinkel) of crashed military
ϑ
aircraft (according to [
2
])
Hits that result in relevant damages to safety-related buildings have an even smaller
probability of occurrence.
Numerous studies were performed with regards to possible scenarios of an
accidental airplane crash in the beginning of the 1970s. The result for the design
of a nuclear power plant was the crash first of a Starfighter and later of a Phantom,
representing many possible events (Table
13.1
).
For the older nuclear power plants in Germany (cf. Table
12.2
) the crash of a
military aircraft of the model Starfighter (Fig.
13.2
) with a mass of 13 t and an
impact velocity of mach 0.30 (
102 m/s or 367 km/h) was used as a design basis.
For newer nuclear power plants and nuclear facilities in Germany
(cf. Fig.
13.3
) with a mass of 20 t and an impact velocity of mach 0.65 (
¼
215 m/s or
774 km/h) was assumed as covering event. A load function was established for this
case in 1973 (cf. [
12
]), which was finally included in the RSK-LL in 1981 [
6
]. The
possible impact angles are assumed between 0 and 90
. Normally the worst load
case perpendicular to the impact surface is assumed for design.
An analysis shows that the load parameters (mass, speed) of over 90 % of the
observed accidental crashes lie beneath the load assumptions (Phantom) of the
newer German nuclear power plant design requirements.
¼
