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Analysis on the Relationship Between Layout and Consumption of Face Cutters on Hard Rock Tunnel Boring Machines (TBMs)

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The consumption of TBM disc cutters is influenced by the ground conditions (e.g. intact rock properties, rock mass properties, etc.), the TBM boring parameters (e.g. thrust, RPM, penetration, etc.) and the cutterhead design parameters (e.g. cutterhead shape, cutter layout). Previous researchers have done much work on the influence of the ground conditions and TBM boring parameters on cutter consumption; however, limited research has been found on the relationship between the cutterhead design and cutter consumption. The purpose of the present paper is to study the influence of layout on consumption for the TBM face cutters. Data collected from six tunnels (i.e. the Røssåga Headrace Tunnel in Norway, the Qinling Railway Tunnel in China, tubes 3 and 4 of the Guadarrama Railway Tunnel in Spain, the parallel tubes of the Vigo–Das Maceiras Tunnel in Spain) were used for analysis. The cutter consumption shape curve defined as the fitted function of the normalized cutter consumption versus the cutter position radius is found to be uniquely determined by the cutter layout and was used for analysis. The straightness and smoothness indexes are introduced to evaluate the quality of the shape curves. The analytical results suggest that the spacing of face cutters in the inner and outer parts of cutterhead should to be slightly larger and smaller, respectively, than the average spacing, and the difference of the position angles between the neighbouring cutters should be constant among the cutter positions. The 2-spiral layout pattern is found to be better than other layout patterns in view of cutter consumption and cutterhead force balance.
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Vol.:(0123456789)
1 3
Rock Mech Rock Eng (2018) 51:279–297
https://doi.org/10.1007/s00603-017-1320-1
ORIGINAL PAPER
Analysis ontheRelationship Between Layout andConsumption
ofFace Cutters onHard Rock Tunnel Boring Machines (TBMs)
QiGeng1,2,3· AmundBruland3· FranciscoJavierMacias3,4
Received: 20 December 2016 / Accepted: 9 September 2017 / Published online: 15 September 2017
© Springer-Verlag GmbH Austria 2017
slightly larger and smaller, respectively, than the average
spacing, and the difference of the position angles between
the neighbouring cutters should be constant among the cutter
positions. The 2-spiral layout pattern is found to be better
than other layout patterns in view of cutter consumption and
cutterhead force balance.
Keywords Tunnel boring machine· Disc cutter layout·
Disc cutter consumption· Shape curve
Abbreviations
TBM Tunnel boring machine
CAI Cerchar abrasivity index
CLI™ Cutter Life Index™
UCS Uniaxial compressive strength
BTS Brazilian tensile strength
VHNR Vickers hardness number of rock
RIAT Rolling Indentation Abrasion Test
GRA Grey relational analysis
RR The Robbins TBM applied in the Røssåga
Project
WQ The Wirth TBM applied in the Qinling Project
WG The Wirth TBM applied in the Guadarrama
Project
HG The Herrenknecht TBM applied in the Guadar-
rama Project
WV The Wirth TBM applied in the Vigo–Das Macei-
ras Project
HV The Herrenknecht TBM applied in the Vigo–Das
Maceiras Project
D & B Drill and blast tunnelling
CCS Constant cross section
CSM Colorado school of mines
Tav The averaged applied gross cutter thrust (kN)
RPM Cutterhead revolution per minute (rpm)
Abstract The consumption of TBM disc cutters is influ-
enced by the ground conditions (e.g. intact rock properties,
rock mass properties, etc.), the TBM boring parameters (e.g.
thrust, RPM, penetration, etc.) and the cutterhead design
parameters (e.g. cutterhead shape, cutter layout). Previous
researchers have done much work on the influence of the
ground conditions and TBM boring parameters on cutter
consumption; however, limited research has been found on
the relationship between the cutterhead design and cutter
consumption. The purpose of the present paper is to study
the influence of layout on consumption for the TBM face
cutters. Data collected from six tunnels (i.e. the Røssåga
Headrace Tunnel in Norway, the Qinling Railway Tunnel in
China, tubes 3 and 4 of the Guadarrama Railway Tunnel in
Spain, the parallel tubes of the Vigo–Das Maceiras Tunnel
in Spain) were used for analysis. The cutter consumption
shape curve defined as the fitted function of the normal-
ized cutter consumption versus the cutter position radius is
found to be uniquely determined by the cutter layout and was
used for analysis. The straightness and smoothness indexes
are introduced to evaluate the quality of the shape curves.
The analytical results suggest that the spacing of face cut-
ters in the inner and outer parts of cutterhead should to be
* Qi Geng
gengqi8902@gmail.com
1 School ofConstruction Machinery, Chang’an University,
Xi’an710064, China
2 State Key Laboratory forManufacturing Systems
Engineering, Xi’an Jiaotong University, Xi’an710049, China
3 Department ofCivil andTransport Engineering, NTNU,
7491Trondheim, Norway
4 SINTEF Building andInfrastructure, Rock andSoil
Engineering, 7491Trondheim, Norway
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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Thesis
The use of hard rock tunnel boring machines (TBMs) has become widely and generally used with success but in too many cases, due to unanticipated situations and/or inappropriate assessments, with catastrophic consequences. Hard rock tunnel boring involves major investments and high levels of geological risk, which require reliable performance predictions and cutter life assessments. Hard rock tunnel boring leads the interaction between the rock mass and the machine, which is a process of great complexity. The tunnelling system around the excavation process has a great relevance in the final goal of performance predictions for hard rock TBMs, which is the estimation of time and cost. The overall aim of this thesis is to build on the existing knowledge of tunnel boring and wear processes, technology and capacity, thus enhancing performance prediction and cutter life assessments in hard rock tunnel boring projects. The prediction model for hard rock TBMs developed by the Norwegian University of Science and Technology (NTNU) is based on a combination of field performance data, engineering geological back-mapping, and laboratory testing. The development of TBM technology during recent decades, and the possible influence of parameters not considered in previous versions, has made revision of the model to improve prediction accuracy an essential requirement. TBM specifications, the penetration rate and cutter life models have been revised and extended to adapt to the current technology. In addition, it has been incorporated a new definition of the rock mass fracturing, the influence of the cutterhead velocity (rpm) on penetration rate on the in response to the results of in-situ trials 'RPM tests' and cutter thrust on cutter life. The tunnel length effect on time consumption for the tunnelling activities has been introduced for the estimation of the machine utilization and therefore in the advance rate model. A revised and extended version of the current version of the NTNU prediction model for TBM performance and cutter life has been published included in this thesis. Cutter consumption and parameters such as cutter ring wear play a significant role in performance and cost predictions, especially in hard rock conditions. Cutter wear involves a complex tribological system in interaction with the geological properties of the rock mass. Existing laboratory test methods fail to reproduce wear behaviour encountered during tunnel boring. Because of this, and the importance of cutter wear, it was considered of interest to develop a new rock abrasivity test method for tool life assessments in hard rock tunnel boring: The Rolling Indentation Abrasion Test (RIAT). Understanding the processes and failure mechanisms during cutter wear enabled new knowledge to be applied as part of the development of the new rock abrasivity test method for laboratory use. In addition, cutter wear mechanisms affecting cutter rings during tunnel boring might lead to better cutter consumption predictions and future improvements in cutter ring development.
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