A three-dimensional finite element simulation model for shield-driven tunnel excavation is presented. The model takes into account all relevant components of the construction process (the soil and the ground water, the tunnel boring machine with frictional contact to the soil, the hydraulic jacks, the tunnel lining and the tail void grouting). The paper gives a detailed description of the model components and the stepwise procedure to simulate the construction process. The soil and the grout material are modelled as saturated porous media using a two-field finite element formulation. This allows to take into account the groundwater, the grouting pressure and the fluid interaction between the soil and slurry at the cutting face and between the soil and grout around the tail void. A Cam-Clay plasticity model is used to describe the material behaviour of cohesive soils. The cementitious grouting material in the tail void is modelled as an ageing elastic material with time-dependent stiffness and permeability. To allow for an automated computation of arbitrarily long and also curvilinear driving paths with suitable finite element meshes, the simulation procedure has been fully automated. The simulation of a tunnel advance in soft cohesive soil below the ground water table is presented and the results are compared with measurements taken from the literature. Copyright © 2004 John Wiley & Sons, Ltd.

A 3D finite element simulation model for TBM tunnelling in soft ground

Recurrent neural networks for real-time prediction of TBM operating parameters

A numerical study of the effect of soil and grout material properties and cover depth in shield tunnelling

In order to extend the application field of Earth Pressure Balance (EPB) tunnel machines to various soil conditions, the soil to be excavated has to be treated with additives in order to modify its mechanical properties, changing it into a plastic paste. Sometimes the grain size distribution is also changed with the use of fine-sized materials. The performance of the conditioned soil should be evaluated with tests that are able to describe its mass behavior, but very little research has been carried out in this field. Often the choice of the conditioning agent set and its control during the excavation is made on a trial-and-error basis during the excavation process. The slump cone test performed on conditioned material is a fast and low-cost way of checking this behavior both in the laboratory and on the job site. The results of a test program on different conditioned non-cohesive soils using the slump cone test are presented and discussed. The influence of the water content and the amount of conditioning foam has been studied, and the feasibility of this type of test for the control of EPB conditioned soil has been assessed.

Using the Slump Test to Assess the Behavior of Conditioned Soil for EPB Tunneling

Electro-hydraulic proportional control of thrust system for shield tunneling machine

This book is translated from German. The development potential of the mechanised shield tunnelling method is far greater than that of the shotcrete method and other traditional tunnelling machines because it is a safer, more effective method of tunnel construction. This book considers the planning of the construction method and design of the machine in harmony with the geological and hydrological conditions, settlement requirements and safety considerations. The technological developments in Germany and world-wide are presented. The book includes chapters on tunnel lining, tailskin seals, grouting and injection procedures, open-faced shields, compressed air shields, slurry shields, earth pressure balance shields, combined shields and special configuration shields and special construction methods.

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Mechanised Shield Tunnelling

Das Buch dokumentiert den weltweit hohen Entwicklungsstand der Schildvortriebstechnik im Jahre 1994. Die Grundlagen, die unterschiedlichen Schildtypen mit ihren Entwicklungen, die Ausruestungen sowie der Stand der Vertragswerke unter Beruecksichtigung der Risikoabgrenzung zwischen dem Auftraggeber, Auftragnehmer und Maschinenhersteller werden zusammengefasst. Es ist ein Gemeinschaftswerk mehrerer Autoren, die ihre jeweiligen Spezialkenntnisse eingebracht haben. In insgesamt 17 Kapiteln wird praktisch das ganze Gebiet des maschinellen Schildvortriebs dargestellt. Beginnend mit dem Grundsaetzlichen, wie Setzungen, Hohlraumstuetzungen, Konstruktion und Berechnungsansaetzen werden nachfolgend bauliche Gesichtspunkte, wie Foerdereinrichtungen, Separation, Deponierung, Tunnelsicherung, Schildschwanzdichtungen, Verpress- und Injektionsverfahren dargestellt. Nach der Beschreibung der verschiedensten Schildtypen und Sonderverfahren wird noch auf Randgebiete, wie Vermessung und Steuerung sowie Arbeitssicherheit und vertragliche Gesichtpunkte eingegangen. Viele Bilder, Zeichnungen und Diagramme erlaeutern den Text.

Gerhard Wehrmeyer

Papers

Mechanised Shield Tunnelling

Maschineller Tunnelbau im Schildvortrieb

The Tunnel Lining

Excavation Tools and Excavation Process

Earth Pressure Balance Shields