Forecasting penetration and wear for TBM drives in hard rock – Results from the ABROCK research project / Prognose von Penetration und Verschleiß für TBM‐Vortriebe im Festgestein – Erkenntnisse aus dem Forschungsprojekt ABROCK

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

“…At the Chair for Subsurface Engineering of the Montanuniversität Leoben, research work has been underway for many years on a disc force measurement system for each individual disc and also a 3D face monitoring system [20] [23] [24] [25] [27]. In the long term, the interaction behaviour of cutting tools with the face will be researched through research into the fracturing behaviour of various rocks in parallel with the performance of numerical simulations of the disc cutting process.…”

Section: Research Work To Investigate the Interaction Behaviour Of Mamentioning

confidence: 99%

The determination of performance‐ and payment‐relevant parameters in TBM tunnelling – State of the technology and outlook / Ermittlung leistungs‐ und vergütungsrelevanter Parameter für TVM‐Vortriebe – Stand der Technik und Ausblick

Galler

Handke²,

Nolden³

2014

Self Cite

The success of mechanised tunnelling is greatly influenced by the interactive behaviour of machine and ground. A multitude of published research and practice reports documents the problem of a targeted forecast based on tests and forecasting models [19]. The paper describes the currently used methods of estimating performance-relevant parameters, including current research into the subject of crack propagation in solid rock and developments in disc force measurement on the tunnel boring machine and its forecasting from laboratory tests. IntroductionIn order to determine a theoretical performance forecast for a TBM drive at the design stage, the entire tunnelling process is divided into partial elements and process activities. These include, at the interface to the ground, 1:1 measurements of disc forces and in the future also the minidisc cutting test newly developed at the Montanuniversität Leoben. Final statements to forecast the performance are, however, first possible based on knowledge of the in-situ stress conditions, the prevailing geological and hydrogeological conditions in interaction with the tools used and the tunnel boring machine -in other words, through tests during the construction phase. Performance-relevant parameters in TBM tunnellingState of the technology 2.1 OverviewThe resulting advance rate is determined by the interaction of geological, mechanical and process-technical and construction operational factors. The cutterhead penetration is defined as the average advance into a rock or rock mass for one single rotation of the cutterhead [1]. The penetration in collaboration with the disc track spacing greatly determines the formation of fractures in the rock while boring solid rock. With decreasing size of the chips and increasing fines content in the muck, the danger of wear and clogging increase, and this is worsened by insufficient material transport. In cohesive soils, cutting wheels with a EinleitungZur Ermittlung der theoretischen Leistungsprognose eines TVM-Vortriebs im Planungsstadium wird der gesamte Vortriebsprozess in Teilelemente und Prozessabläufe untergliedert. Hierzu gehören an der Schnittstelle zum Baugrund auch 1:1-Diskenkraftmessungen sowie zukünftig u. U. ein an der Montanuniversität Leoben neu entwickelter Minidiskenschneidversuch. Endgültige Aussagen zur Leistungsprognose sind i.d.R. aber erst auf Basis der in situ vorherrschenden Spannungsverhältnisse, der anstehenden geologischen und hydrogeologischen Verhältnisse in Wechselwirkung mit dem eingesetzten Werkzeug, der Tunnelvortriebsmaschine -also durch Versuche während der Bauausführung -möglich. R. Galler/D. Handke/M. Nolden · The determination of performance-and payment-relevant parameters in TBM tunnelling -State of the technology and outlook small degree of opening tend to clog. With the danger of clogging, the wear also increases, and is worsened by insufficient material transport from the face.

“…quartz content, uniaxial compressive strength, VHNR, CAI, CLI. A summary and discussion of the various wear prediction models is omitted here, instead referring to the applicable works of Spiegl [18], Frenzel [5] or Schneider et al [19].…”

Section: Effects On Wear Prediction and Tool Selectionmentioning

confidence: 99%

Rock mass‐scale factors with an influence on tool wear in the mechanised tunnelling process in hard rock

Plinninger¹,

Alber

Düllmann³

2018

Wear to the tools used for excavate the rock mass has a significant relevance for the cost and performance of tunnel drives in hard rock. This applies in particular to mechanised tunnelling processes, where the effect of wear is an important factor for system availability. At the moment, laboratory tests and derived abrasiveness indices like the Cerchar Abrasiveness Index (CAI) or the Rock Abrasivity Index (RAI) provide the basis for evaluation of tool wear. It should however be noted that such index values can only take into account influential factors on the scale of the intact rock. Influential factors on the scale of the rock mass, for example mixed‐face conditions, unstable face conditions, blockiness or the primary and secondary stress states at the face, can also be significant for the tool wear that is actually experienced. The possible consequences of such disadvantageous effects, which for example can cause catastrophic failure of tools, can represent many times the abrasiveness of the intact rock.