The deployment of engineering models and design methods divorced from the effect that mechanised shield tunnelling with tunnel boring machines (TBMs) has on concrete segmental linings (CSLs) can lead to either material waste or structural damage within the tunnel design life. Most research to date on CSL behaviour during construction neglects the sequential ring loading and TBM-lining transverse interactions, which this thesis proved to be key in the short and long term behaviour of CSLs and whose study is essential if the design and maintenance of CSL structures is ever to be optimised. This thesis investigates the longitudinal and transverse behaviour of CSL structures simultaneously backfilled with bicomponent grouts (BGs) during tunnelling, and how this early response influences long term behaviour. The research work is drawn on three pillars that enable cross-validation of conclusions: analytical models, three-dimensional numerical simulations and the interpretation of the Crossrail's Thames tunnel (CTT) field data, which included distributed fibre optic strain (DFOS) data. A theoretical framework ranging from construction loading scenarios to the mechanisms underlying structural damage is described for the future development of limit state design methods. Analytical models of longitudinal behaviour are also proposed. The study of joint geometries, temporary spear bolts and DFOS sensing in CSL construction monitoring is included as ancillary research. The solution developed for a sequential elastic rod subjected to a trilinear temperature profile and in shear interaction with the elastic ground predicts accurately the early tunnel pre-stressing relaxation caused by grout hardening, e.g. ≈50% in the CTT. The proposed sequential elastic beam model, which incorporates the effects of stage-varying net TBM moments, transverse loads and lining pressure gradients within the tunnel unsupported length, estimates satisfactorily the history of tunnel beam response during construction for a realistic expression of the lining stiffness. A potential damage assessment method for the early detection of tunnel sections prone to ring joint damage was proposed. The TBM-lining transverse interaction determines the CSL ring behaviour at the early stages of tunnelling. The ring response resultant from this interaction is irrecoverable and contributes to the long term total deformations and internal forces; in tunnels excavated in grounds with Ko≈1, it becomes the major source of ring distortion. The main transverse actions are the sealing pressures, which are inversely related to the tail clearance, and the transverse load of oblique hydraulic jacks. When the non-bedded rings are eccentric with respect to the shield tail, the ring distortion increases the risk of cracking near the rear corners and spalling at the ram pad interspaces of constrained segments. The ring distortion is directly related to the pressure gradients, the unsupported length and the ring flexibility. When individual segments rotate outwards under the action of transverse ram loads, e.g. the outer springline segment during pronounced TBM steering around a horizontal curve, the localised action of the sealing pressures can result in longitudinal cracking at the intrados of the segment front. This study represents a qualitative leap towards the optimisation of CSL design, shifting the attention of researchers and designers to TBM-lining transverse interactions as the most determinant factor of structural response during construction in CSLs simultaneously backfilled with BGs.

Contrary to the linings of conventionally driven tunnels, the linings of tunnels bored by tunnel boring machines (TBMs) consist of precast concrete segments which are articulated or coupled at the longitudinal and circumferential joints. There are several analytical and numerical structural analysis methods proposed for the design of TBM segmental linings. In this thesis study, different calculation methods including elastic equation method and two dimensional (2D) and three dimensional (3D) beam &ndash / spring methods are compared and discussed. This study shows that in addition to the characteristics of concrete segments, the mechanical and geometrical properties of longitudinal and circumferential joints have significant effects on the structural behavior of segmental lining.

Cette thèse vise à étudier le comportement de revêtement articulé du tunnel en développant une nouvelle approche numérique à la Méthode de Réaction Hyperstatique (HRM) et la production des modèles numériques en deux dimensions et trois dimensions à l'aide de la méthode des différences finies (FDM). L'étude a été traitée d'abord sous charges statiques, puis effectuée sous charges dynamiques. Tout d'abord, une étude bibliographique a été effectuée. Une nouvelle approche numérique appliquée à la méthode HRM a ensuite été développée. En même temps, un modèle numérique en deux dimensions est programmé sur les conditions de charge statique dans le but d'évaluer l'influence des joints, en termes de la distribution et des caractéristiques des joints, sur le comportement du revêtement articulé de tunnel. Après cela, des modèles complets en trois dimensions d'un seul tunnel, de deux tunnels horizontaux et de deux tunnels empilés, dans lesquels le système des joints est simulé, ont été développés. Ces modèles en trois dimensions permettent d'étudier le comportement non seulement du revêtement du tunnel, mais encore le déplacement du sol entourant le tunnel lors de l’excavation. Un modèle numérique en trois dimensions simplifié a ensuite été réalisé afin de valider la nouvelle approche numérique appliquée à la méthode HRM.Dans la dernière partie de ce mémoire, la performance du revêtement articulé du tunnel sous chargements dynamiques est prise en compte par l’analyse quasi-statique et dynamique complète en utilisant le modèle numérique en deux dimensions (FDM). Un modèle HRM a également été développé prenant en compte des charges quasi-statiques. Les différences de comportement de tunnel sous chargements statiques et sismiques sont mises en évidence et expliquées. / This PhD thesis has the aim to study the behaviour of segmental tunnel lining by developing a new numerical approach to the Hyperstatic Reaction Method (HRM) and producing two-dimensional (2D) and three-dimensional (3D) numerical models using the finite difference method (FDM). The study first deals with under static loads, and then performs under dynamic loads. Firstly, a literature review has been conducted. A new numerical approach applied to the HRM has then been developed. At the same time, a 2D numerical model is programmed regarding static loading conditions in order to evaluate the influence of the segmental joints, in terms of both joint distribution and joint stiffness characteristics, on the tunnel lining behaviour. After that, full 3D models of a single tunnel, twin horizontal tunnels and twin tunnels stacked over each other, excavated in close proximity in which the joint pattern is simulated, have been developed. These 3D models allow one to investigate the behaviour of not only the tunnel lining but also the displacement of the ground surrounding the tunnel during the tunnel excavation. A simplified 3D numerical model has then been produced in order to validate the new numerical approach applied to the HRM. In the last part of the manuscript, the performance of the segmental tunnel lining exposed to dynamic loading is taken into consideration through quasi-static and full dynamic analyses using 2D numerical models (FDM). A new HRM model has also been developed considering quasi-static loads. The differences of the tunnel behaviour under static and seismic loadings are highlighted.

In der vorliegenden Arbeit wurde die Ringfuge einer Tübbingschale hinsichtlich der Möglichkeit einer Reibungskopplung zur Übertragung von Scherkräften, wie sie bei relativen Ringversätzen auftreten können, untersucht. Ein Schwerpunkt lag dabei in der Ermittlung von Scherwiderständen an unterschiedlich profilierten Betonprobekörpern mit direktem Betonkontakt bzw. mit Verwendung einer Zwischenlage. Neben diesen Scherversuchen wurde zudem die Entwicklung der Normalkraft in der Ringfuge untersucht. Dabei wurden zur Verfügung gestellte Messdaten eines In-situ-Versuchs am Neuen Schlüchterner Tunnel ausgewertet. Weitere Erkenntnisse lieferte ein unter Laborbedingungen durchgeführter Bauteilversuch an Originaltübbings. Letztere wurden mittels Spanngliedern über einen Zeitraum von drei Jahren verspannt. Der Spannkraftverlust infolge von Kriechen und Schwinden des Betons sowie der Relaxation der Dichtungsprofile und der Spannglieder wurde kontinuierlich ermittelt