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walls and partial failure of roofs, damage that corresponds to extensive damage (grade 3 in
the EMS-98 macroseismic scale).
For the houses presenting complete damage, equivalent to damage grade 4 or 5 on the
EMS-98 macroseismic scale, it can be supposed that new houses were reconstructed. Some
of themwere reconstructed using the building style progressively adopted by richer families
in this region since the second part of the seventeenth century (
Figure 8.7
D
). The castle
and the church were rebuilt in the years following the earthquake, but even if intensive
works were required to stabilize the two edifices after the earthquake, they did not collapse
(Nicolas Ignace de Woelmont,
Histoire de la maison de Woelmont
).
These observations and analysis suggest that most of the damage to the buildings in
the centre of Soiron ranged from extensive to complete (grades 3 to 5 in the EMS-98
damage scale). Following our inventory, one-third of the damaged houses revealed extensive
damage. These houses can be considered as the less vulnerable ones of the building stock of
that epoch in Soiron, meaning very likely vulnerability class B at the best. Based on these
hypotheses, the intensity can be evaluated as VIII on the EMS-98macroseismic scale. This
and not incompatible with the fact that the more vulnerable houses could have presented
complete damage.
8.6 Discussion and conclusions
In this chapter, we have presented the methodological background associated with the
investigation of the damage caused by past earthquakes in the region of Western Europe
extending from the Lower Rhine Embayment to the southern North Sea. We have applied it
to the study of seven earthquakes that represent typical seismic activity of this area and for
which we have been able to retrieve relevant information on the characteristics, location, and
extent of damage. Our study furnishes information on important seismological, geological,
geographical, and architectural aspects influencing the consequences of earthquakes and
helping to validate earthquake risk assessment.
8.6.1 Earthquake vulnerability of Western Europe
The precise inventory of the damage caused by the 1983 M
=
4.6 Liege and 1992
M
5.3 Roermond earthquakes has provided fundamental information on the present-
day high seismic vulnerability of the major centres of population in this part of Europe.
The vulnerability is especially high in regions where industrialization took place dur-
ing the nineteenth and the early twentieth centuries. There are two main reasons for this
high vulnerability. The first one is the very high population density, which explains the
elevated estimated losses during the 1992 Roermond earthquake, despite the maximum
macroseismic intensity barely reaching VI (EMS-98 scale). The second aspect to take into
consideration is the extremely high vulnerability of the building stock composed of low-rise
=
