2035
Response of piled buildings to deep excavations in soft soils
Déformations des bâtiments liés aux excavations profondes situé dans les sols mous
Korff M.
Deltares and Cambridge University
Mair R.J.
Cambridge University
ABSTRACT: This paper explores the building displacements related to deep excavations for a case study from the Netherlands: the
construction of the North South Metro Line in Amsterdam. The overall goal of the analysis of the displacement is to study the
interaction of deep excavations with piled buildings. The response of buildings is governed by the soil displacements resulting from
the excavation. These displacements are described in a second, related paper in this conference. In this paper, the response of the piled
buildings is described.
RÉSUMÉ : Les auteurs ont analysé déformations des bâtiments liés aux excavations profondes à Amsterdam pour la Ligne nord/sud.
L'objectif général de l'analyse des déformations est d'étudier l'interaction des excavations profondes avec des bâtiments sur pieux. La
réponse des bâtiments est régie par les déformations du sol résultant de l'excavation. Ces déformations, du niveau de la surface et de
niveaux plus profonds, sont décrites dans un article connexe à cette conférence. Dans le document présent, la réponse des bâtiments
sur pieux est décrite.
KEYWORDS: deep excavation, ground displacement, piles.
1 INTRODUCTION
The North-South Line in Amsterdam passes under the historical
centre of the city in twin tunnels. Five underground stations are
currently under construction. Rokin, Vijzelgracht and
Ceintuurbaan Station are three of the deep stations in the
historic city centre. They are built using the top down method,
see Figure 1. In a related paper for this conference by the same
authors, the construction method and ground displacements
related to the deep excavations have been described. The
settlement measurements for the Amsterdam deep excavations
have been compared to several, mostly empirical, relationships
to determine the green field surface displacements and
displacements at depth. In summary, the surface displacement
behind the wall is 0.3 – 1.0% of the excavation depth, if all
construction works are included. Surface displacements behind
the wall can be much larger than the wall deflections and
become negligible at 2-3 times the excavated depth away from
the wall. The shape of the displacement fits the proposed profile
by (Hsieh and Ou 1998) best. In all three of the Amsterdam
cases, the largest effect on the ground surface displacement can
be attributed to the preliminary activities, which include
amongst others the diaphragm wall construction, jet grout strut
installation and construction of the roof, and took in total about
4 years. See Table 1 for details.
Table 1 Construction activities and dates for Ceintuurbaan
Construction activity
End date
Base monitoring start 2001
2003-11-01
Preliminary activities
2007-04-01
Excavation to NAP –6.2m
2007-09-13
Excavation to NAP –15.3 m
2007-12-10
Excavation to NAP –19.4 m
2008-03-01
Excavation to NAP –24 m
2008-08-01
Excavation to NAP –25.6 m
Floor construction, pumping test
2009-06-24
The actual excavation stage caused only about 25-45% of the
surface displacements, with 55-75% attributed to the
preliminary activities. At larger excavation depths the influence
zone is significantly smaller than 2 times the excavation depth.
This paper describes the building displacements related to
the excavation works in more detail.
Figure 1 Cross section of Ceintuurbaan Station with soil profile and
extensometer locations.
1st sandlayer
Holocene soft clay
Eemclay
Intermediate sandlayer
Glacial clay
2nd sandlayer
3rd sandlayer
