7
purpose to present the most recent time series is to illustrate
that the movements are still ongoing. Referring to what has
been discussed above, it is clear that the damage is caused
by the cumulative effect of all past and current movements,
and not just by the additional movements taking place in
the period 2016–2021.
As indicated above, all observed damage occurred in
the period after the closure of the Winterslag coal mine.
Figures 6 and 7 show damage to masonry walls and refer
to a single house and a large building (i.e., school), respec-
tively. For the example in Figure 7, the new damage is a
re-activation of cracks that occurred during the subsidence
phase. These old cracks were simply filled with mortar and
no further reinforcement was locally installed. The rate of
vertical movements in these two examples over recent years
is for Figure 7b about half the rate of Figure 6b. However,
there is a clear trend in the variation of the horizontal
movement in Figure 7c, i.e., just over 1 mm/year. For the
first case, the horizontal movements are relatively small
and more of a fluctuation. So far, horizontal movements
above deep coal mines have only been studied to a limited
extent. As mentioned above, the horizontal strain due to a
curvature in the subsidence profile is calculated, but here
absolute horizontal movements are measured. The latter is
successfully investigated during movements towards exca-
vations or slope instability, but so far not really above long-
wall panels. It is certainly a parameter which needs more
attention in the future.
Figure 8 shows the damage to the road surface. The
pictures cover two parallel roads at a distance of 10 to 15 m.
The amount of traffic is significantly different. One road
was built after the mine closure the other was completely
renovated during that period. Therefore, it can be con-
cluded that the damage is clearly related to the upsidence.
Further research is needed to relate the damaged zones to
the underlying mining geometry and the position of the
faults. The horizontal movement at the site is about 1 mm
a year and the trend is clear (Figure 8c).
(a)
(b) (c)
Figure 6. Examples of damage to masonry of a house, observed after the closure of the coal mines. a. Pictures b &c. On-going
vertical (b) and horizontal (c) surface movement during the period 2016–2021 (average, minimum and maximum values of
four neighboring data points)
purpose to present the most recent time series is to illustrate
that the movements are still ongoing. Referring to what has
been discussed above, it is clear that the damage is caused
by the cumulative effect of all past and current movements,
and not just by the additional movements taking place in
the period 2016–2021.
As indicated above, all observed damage occurred in
the period after the closure of the Winterslag coal mine.
Figures 6 and 7 show damage to masonry walls and refer
to a single house and a large building (i.e., school), respec-
tively. For the example in Figure 7, the new damage is a
re-activation of cracks that occurred during the subsidence
phase. These old cracks were simply filled with mortar and
no further reinforcement was locally installed. The rate of
vertical movements in these two examples over recent years
is for Figure 7b about half the rate of Figure 6b. However,
there is a clear trend in the variation of the horizontal
movement in Figure 7c, i.e., just over 1 mm/year. For the
first case, the horizontal movements are relatively small
and more of a fluctuation. So far, horizontal movements
above deep coal mines have only been studied to a limited
extent. As mentioned above, the horizontal strain due to a
curvature in the subsidence profile is calculated, but here
absolute horizontal movements are measured. The latter is
successfully investigated during movements towards exca-
vations or slope instability, but so far not really above long-
wall panels. It is certainly a parameter which needs more
attention in the future.
Figure 8 shows the damage to the road surface. The
pictures cover two parallel roads at a distance of 10 to 15 m.
The amount of traffic is significantly different. One road
was built after the mine closure the other was completely
renovated during that period. Therefore, it can be con-
cluded that the damage is clearly related to the upsidence.
Further research is needed to relate the damaged zones to
the underlying mining geometry and the position of the
faults. The horizontal movement at the site is about 1 mm
a year and the trend is clear (Figure 8c).
(a)
(b) (c)
Figure 6. Examples of damage to masonry of a house, observed after the closure of the coal mines. a. Pictures b &c. On-going
vertical (b) and horizontal (c) surface movement during the period 2016–2021 (average, minimum and maximum values of
four neighboring data points)