i137 GEO binnen - GeoTechniek

Rigidity of the station
The tilt meters have been installed in the station to
calculate the vertical deformation of the south side
of the station under the assumption that the station
sections behave rigid. During the building activities
this hypothesis was questioned, because of small
leakages of the station and unexplainable differences
between results of the automatic monitoring
system and the measurements of RPW. To investigate
the rigidity of the station additional points were placed
in the centre of the station. With these points
cross profiles of the station could be constructed.
However, after installation of these points no
significant displacements of the station were
measured anymore. As a result no conclusion could
be drawn about the hypothesis of the rigidity of the
station sections (Huisman and Berkelaar, 2006).
CONCLUSIONS AND
RECOMMENDATIONS
CONCLUSIONS
The most prominent risk, interference of operation of
the metro station, did not occur. Full accessibility of
all services was maintained during all building
activities.
The monitoring system operated according to
contract specifications. The on-line presentation and
checking on hazard warning levels was very helpful in
detecting the effect of building activities on the
metro station. The examples in this paper show how
monitoring has been used to control building risks.
RECOMMENDATIONS
As a result of the problems with refraction due to the
semi-confined structure of the station and the
questioned rigidity of the station, a system with
more internal control was recommended for phase
2 of the project and for semi-confined spaces in
general. With 2 tachymeters points are measured
from different positions. Refraction problems will be
eliminated and/or detected in time because it is
unlikely that refraction and temperature peaks would
have the same effect on measurements from two
directions. The monitoring specifications for phase 2
were set up in such a way that the recommendations
from phase 1 were taken into account. Two tachymeters
were specified in combination with crack
meters placed over the station section joints.
ACKNOWLEDGEMENTS
The authors acknowledge the graphical contributions
from Ton de Keiser of Rotterdam Public Works –
Engineering Department.
DEFORMATION MONITORING OF THE UNDERGROUND METRO STATION ROTTERDAM CS
FIGURE 9
REFERENCES
– Berkelaar, R. (2006) Coping with underground risks
during the development of a new underground metro
station in Rotterdam, Proceedings of the 10th IAEG
International Congres, Nottingham, United
Kingdom.
– Huisman, L. (2005) Deformatiemetingen staartspoor
Metro CS week 25 (Results of verification measurements
metro station week 25), Internal memo RPW,
Rotterdam, the Netherlands.
– Huisman, L., and Berkelaar, R. (2006), Evaluatie
monitoring Metro CS Fase I (Evaluation monitoring
metro station CS Phase 1), Internal report RPW,
R.2006.012.RR, Rotterdam, the Netherlands.
– Luijten, C.J.L.M. (2002) Betuweroute en grondverzet,
Handboek Bouwstoffenbesluit (Betuweroute
and earth moving, Manual of building materials
regulations), part 9-16 page 1-20, Weka Uitgeverij,
Amsterdam, the Netherlands.
– Man, C.H. (2005) Een systematiek voor risicomanagement
tijdens de uitvoeringsfase in een complex
stedelijk civieltechnisch project (Systematic approach
for risk management in complex urban construction
projects), M.Sc. thesis C.H. Man, University of
Twente, Enschede, the Netherlands.
RELATION BETWEEN STATION TEMPERATURE AND VERTICAL DEFORMATION.
– Visser, A. (2005) Meetopzet deformatiemetingen
Metro CS (Design of deformation measurements
metro CS), Internal memo RPW, Rotterdam,
the Netherlands.
Reprinted with permission from ASCE.
1 Robert Berkelaar is Geotechnical Engineer, MSc
Engineering Geology, Rotterdam Public Works –
Engineering Department, PO Box 6633,
3002 AP Rotterdam, the Netherlands
r.berkelaar@gw.rotterdam.nl
2 Lennard Huisman is Geodetic Engineer, MSc
Geodetic Engineering, Iv-Infra b.v., PO Box 1155,
3350 CD Papendrecht, the Netherlands,
currently working for University of Technology Delft,
Faculty of Aerospace Engineering,
l.huisman@tudelft.nl
3 Cor J.L.M. Luijten is Monitoring Supervisor, MA
Geography, Rotterdam Public Works – Engineering
Department, PO Box 6633, 3002 AP Rotterdam,
the Netherlands, cjlm.luijten@gw.rotterdam.nl
4 Rotterdamse Electrische Tram i.e.
Rotterdam public transport company.
5 Rotterdam Public Works.
GEOinternational – October 2008 43