1735
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
1
Wall structure
Segmental tunnel
Tunnel boringmachine
Tu el boring machine
Box- odules
Lining Frame
Datum element
excavation
Normal element
excavation
Pull jack
Tunnel boring
machine
Datum element
PC steel cable
Normal element
PC steel cable
PC steel cable
Pull jack
B x-module
Tunnel boring machine
t l
l
ll jack
Existing box-module
Finite Element Modelling of Construction Processes of The Modular Approached
Tunnelling Method
Modélisation par éléments finis du processus de construction de la méthode tunnel modulared
K. Komiya
Chiba Institute of Technology, Narashino, Japan
ABSTRACT: A modular approached tunnelling method is a new mechanized tunnelling method which has been developed to
construct large scale tunnels under-crossing the existing railroad tracks or other existing main artery traffics in urban areas. In the
method, a lining frame is first formed in a soil ground by with step-by-step excavation using a small tunnel boring machine and
insertion of a box-module. After completion of the lining frame, the soil within the internal section of the lining frame is excavated. In
this paper, the advancement and excavation processes of the box-modules operations were modelled using the finite element method
in order to investigate the effect of these construction processes on the ground response. The proposed modelling techniques were
applied to simulate a modular approached tunnelling work in soft cohesive soil in Tokyo and the results were compared with the field
measurements.
RÉSUMÉ : Une méthode modulaire approché tunnel est une méthode nouvelle tunnel mécanisé qui a été développée pour construire
des tunnels à grande échelle sous-franchissement des voies ferrées existantes ou d'autres trafics existants artères principales dans les
zones urbaines. Dans le procédé, un premier cadre de revêtement est formé dans un motif en sol à l'étape par étape à l'aide d'une
machine d'excavation du tunnel petite forage et l'insertion d'une boîte module. Après l'achèvement de la trame de revêtement, le sol à
l'intérieur de la section interne du cadre d'habillage est excavé. Dans cet article, les processus d'avancement et l'excavation des
opérations box-modules ont été modélisés à l'aide de la méthode des éléments finis afin d'étudier l'effet de ces processus de
construction sur la réponse du sol. Les techniques de modélisation proposées ont été appliquées pour simuler un travail modulaire,
s'approcha de tunnel dans un sol cohérent doux à Tokyo et les résultats ont été comparés avec les mesures sur le terrain.
KEYWORDS: modular approached tunnelling method, finite element method, constraction process, displacement, soft clay.
1 INTRODUCTION
A modular approached tunnelling method (Nozawa S. 2003) is
a new mechanized tunnelling method which has been developed
to construct large scale tunnels under-crossing the existing
railroad tracks or other existing main artery traffics in urban
areas.
In the method, a lining frame is first formed in a soil ground
by with step-by-step excavation using a small tunnel boring
machine and insertion of a box-module as shown in Figure 1.
After completion of the lining frame, the soil within the internal
section of the lining frame is excavated.
As the excavation by the tunnel boring machine is of small
scale and guided by the existing adjacent box-module, it is
possible to perform safe construction even where the
overburden is small. Therefore, as the modular approached
tunnelling method has a variable for a large cross section with
extremely shallow overburden earth coverage, the method has
been used extensively for the construction of road tunnels under
the existing rail track.
Since many advances such as the development of new
excavation machines have been made in order to optimise the
modular approached tunnelling method, the magnitude of soil
deformation has become small. However even with recent
advancements of the method, the tunnelling in soft clayey
ground, where the SPT-N value is close to zero, is still a major
technical challenge to engineers.
In this paper, the advancement and excavation processes of the
tunnel boring machine and the box-module are newly modelled
using the finite element method in order to investigate the effect
of the step-by-step construction processes on the ground
response. The proposed modelling techniques are applied to
Figure 1. Overview of the modular approached tunnelling.
Figure 2. Construction process of box-module.
simulate a modular approached tunnelling work in Tokyo and
the numerical results are compared with the field measurements.
inite le ent odelling of onstruction rocesses of he odular
Approached Tunnelling Method
odélisation par élé ents finis du processus de construction de la éthode tunnel
modulared
Komiya K.
Chiba Institute of Technology, Narashino, Japan
