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mentioned that all the people left their homes in a hurry: Andenne, Jodoigne, Namur, Sainte-
Marguerite (suburb of Liege), Sint-Truiden, and Tongeren. These observations certainly
correspond to intensity equal to or greater than VI on the EMS-98 macroseismic scale,
confirming the range of intensities assessed from the damage discussed above.
8.5.6.2 Damaged churches during the 1828 earthquake
The earthquake that occurred 23 February 1828 caused severe damage to the architectural
heritage, mainly the churches of Central Belgium. Several historical sources mentioned
damage caused by the earthquake on such buildings: pieces of ceilings falling down, cracks
on walls and vaults, collapse of vaults, the ruin of some parts of buildings, etc, This damage
led to repairs that are sometimes mentioned in the historical sources too: cramp irons on
facades, placing of ties on vaults. We have elaborated an interdisciplinary methodology to
recognize the traces of damage produced by this earthquake on these buildings with the
objective of improving our knowledge of specific historical earthquakes, and also evalu-
ating the vulnerability of the architectural heritage in the perspective of its future preser-
vation.
Seismic damage in churches attested by historical sources
The first step in this analysis
consisted of a survey of the 18 churches for which historical sources mentioned some
damage (
Figure 8.6
)
. Visits to the churches that still exist allowed pathologies corresponding
to those described in the reports on the earthquakes to be identified in some cases. Most of
the damage has been repaired, but it can still be identified in the buildings and associated
with repairs mentioned in historical documents. This is the case for the church of
Autre-
Eglise
(
Figure 8.6
A
): “The building took damage from the 1828 earthquake. The front was
repaired in 1830; the cramp irons visible in the choir to the east up to a window also date
from this epoch” (Tarlier and Wauters,
Geographie et histoire des communes belges
, 1872).
At present, it can be observed that this church is built in stone except for a large part of the
front, which is built in brick and was rebuilt after the earthquake.
In the village of
Marilles
, the tower of the church was also damaged by the 1828
earthquake, as attested by the many cramp irons presently holding the different walls of the
tower (
Figure 8.6
B
). Some of them at the top bear the date 1831, which is the date of the
end of the repair work that followed the earthquake.
The church of
Petit-Hallet
(
Figure 8.6
C
) was repaired in 1829, although it still presents
recognizable damage, as substantial as cracks above and under the windows of the nave
and the choir, many cramp irons in the face of the tower, and cracks in the middle of
the arches of the vaults. This last observation can be directly linked to the descriptions in
historical sources that mentioned that parts of the vault collapsed. Of course, not all the
present pathologies are necessarily linked to the earthquake, and a specific investigation on
the Petit-Hallet church was performed to show which of the existing pathologies and repair
The historical sources mention major damage in the church of
Berloz
as well: cracks
on walls, collapse of the vaults, and ruin of the tower. The two aisles had to be rebuilt in
