An Integrated Approach to Penetration, Advance Rates and Disc Cutter Wear for Hard Rock TBM Drives

The Brenner Base Tunnel, with two main bores and an investigation tunnel running parallel in the middle, crosses the main ridge of the Alps beneath the Brenner Pass and the border of Austria and Italy. The first construction contract was a 10.5 km long investigation tunnel bored by a double shield machine in granite. Numerous investigation measures, laboratory tests and geological face surveys were carried out, and the TBM data was recorded on a 10-second cycle. Due to the large amount of data and the very well known homogeneous geology, it seemed appropriate to develop correlations between the data of the rock mass, the rock and the TBM. Statistically reliable statements could be derived. The unconfined compression strength of the rock, discontinuity parameters and index parameters such as the RMR (Rock Mass Rating), GSI (Geological Strength Index) and RQD (Rock Quality Designation) were compared with the penetration behaviour. GSI values between 30 and 40 showed four times the penetration rate compared to GSI values between 90 and 100. This applies similarly for the RQD, RMR and discontinuity spacing values. The objective was to precisely localize rock mass zones with a high degree of fracturing or faults for the main bores. This is only possible to a limited extent from the face surveys since the sides of the tunnel are not visible between the individual face surveys and the delivered information is not complete. By matching the geological face information with the TBM data, the faulted rock mass zones in the investigation tunnel could be defined well. In addition, experience from the investigation programme and its geotechnical monitoring is described. The constant presence of geologists on the TBM, the installation of measurement segments and continuous probe drilling can be seen as particularly positive. EinleitungBei der Errichtung des Brenner Basistunnels wurde im Erkundungsstollen Aicha in einheitlicher Geologie, dem Brixner Granit, ein 10,5 km langer Stollen mittels einer Doppelschildmaschine aufgefahren. Aufgrund zahlreicher kontinuierlicher und gezielter Erkundungsmaßnahmen, konsequent durchgeführter Ortsbrustaufnahmen während des Vortriebs und in regelmäßigen Abständen durchgeführter Laborversuche ist der Brixner Granit als Gestein und als Gebirge bestens untersucht und bekannt [1]. Die Daten der Tunnelbohrmaschine (TBM) wurden im 10-Sekunden-Takt erhoben. Seismische und geoelektrische Ver-Topics Brenner Base Tunnel -a 10.5 km double shield TBM drive in granite Brenner Basistunnel -10,5 km Doppelschild-TBM im Granit

Section: Korrelation Geologischer Daten Mit Maschinendaten 621 Allgunclassified

Brenner Base Tunnel – a 10.5 km double shield TBM drive in granite / Brenner Basistunnel – 10,5 km Doppelschild‐TBM im Granit

Skuk¹,

Wegscheider²

2015

“…Comparing the modelled rock mass stresses with the results of the wear analysis, it is clearly apparent that high rock mass stresses correlate with high tool wear. A direct relationship between abrasive wear and the stress state in the rock has already been demonstrated in CAI laboratory tests on various rocks [11]. The evaluation of wear data presented in Section 3 shows that this wear behaviour is also qualitatively valid under real tunnelling conditions.…”

Section: Effects Of Rock Mass Stressesmentioning

confidence: 55%

“…This remarkable relationship does not however mean that the wear depends on cutter ring temperatures or vice-versa. The determined temperature distribution of the cutter rings over the individual installation positions does however show that this is not solely controlled by the rotational velocity of the Ein direkter Zusammenhang zwischen abrasivem Verschleiß und dem Spannungszustand des Gesteins konnte bereits durch CAI-Laborversuche an verschiedenen Gesteinen nachgewiesen werden [11]. Die in Kapitel 3 vorgestellte Auswertung der Verschleißdaten zeigt, dass dieses Verschleißverhalten auch unter realen Vortriebsbedingungen qualitativ gültig ist.…”

Section: Wear Against Temperatureunclassified

Does the in‐situ stress state have an effect on tool wear in deep TBM tunnelling?

Rauch¹,

Goliasch²,

Käsling

et al. 2018

Analysis of wear data from a TBM tunnelling project under high overburden shows diverging wear rates on the disc cutters depending on their position in the cutterhead. The disc cutters at inner and middle positions in the cutterhead reach about twice the running distances compared with cutters fitted at pre‐gauge positions. This work shows that the construction of the cutterhead has an impact on the degree of abrasive wear, especially for the gauge positions. Moreover, the analysis shows that the in‐situ stress state correlates significantly with disc cutter wear. Working temperatures of disc cutters were also measured and analysed. In general, the measured temperatures are controlled by the transverse velocity of the disc cutters, which depends on the position of the disc cutter in the cutter head. Furthermore, there is a good correlation between the results of the analysis of disc cutter wear and the measured disc cutter temperatures. It is shown that high temperatures and high cutter wear occur at the same positions in the cutterhead.

“…Further information and the results of current research into disc wear can be found in the investigations of Frenzel, Käsling & Thuro [27] and Alber [28]. The prognosis models available so far determine the primary wear on cutter discs and apply to cutterheads working in open mode (TBM or SM-V1) without face support.…”

Section: Wear Predicition For Shield Tunnelling In Soil 81 No Analogmentioning

confidence: 96%

Abrasiveness and tool wear in shield tunnelling in soil / Abrasivität und Werkzeugverschleiß beim Schildvortrieb im Lockergestein

Köhler¹,

Maidl²,

Martak³

2011

There are currently no recognised prediction models available for the estimation of tool wear in shield tunnelling in soil. This paper describes the current state of knowledge through the interpretation of the available index tests, available correlations and analogies to hard rock. Then follows a discussion of the essential soil properties and the process-related interactions, which can also determine tool wear in soil.