BREAKTHROUGHS IN TUNNELING 2019DRILL & BLAST AND ROADHEADER

RMDS IN DETAIL

Sandvik AB – Sandvik Mining and Rock Technology – Product Division Mechanical Cutting – Uwe Restner

TABLE OF CONTENTS

2

DRILL & BLAST AND ROADHEADER TUNNELING

• Selection criteria for excavation method• Rock & rock mass cuttability assessment• Facts & developments in drill & blast• Latest & ongoing roadheader developments• Closing movie

SELECTION CRITERIA FOR EXCAVATION METHOD3

EXCAVATION METHOD SELECTION CRITERIA

4

ROCK MASS PROJECT ENVIRONMENT

Drill & Blast

Shield Machines

Hardrock TBM

Excavator Attachments

Roadheaders

Rock Compressive Strength

Roc

k M

ass

Con

ditio

ns

Mechanical Excavationwith Breakers / Splitters

MECHANICAL TUNNEL EXCAVATION

5

Mechanical Tunnel

Excavation

Part face excavation

Soft (loose)

rock

Full face excavation

Hard (stable)

rock

ROADHEADER TUNNEL EXCAVATION

6

CAI

–C

ERC

HAR

Abr

asivi

ty In

dex

[mm

]

UCS – Uniaxial (Unconfined) Compressive Strength [MPa]50 100 150 2000

0

1

2

3

4

Limestone (867)UCS=85MPa, CAI=1.1

Sandstone (1197)UCS=80MPa, CAI=2.2

Basalt (64)UCS=119MPa, CAI=2.5

Coal (56)UCS=24MPa, CAI

OVERALL CUTTING PERFORMANCE TOO LOW

7

CUTTING TOOL CONSUMPTION TOO HIGH

8

EXCAVATION METHOD SELECTION CRITERIA

• Complex and variable geology• Free access to tunnel face• Ability for partial face excavation• Smooth excavation process• Not sensitive against squeezing rock mass• High cutting performance in weak and medium

strong rock mass

9

CRITERIA FOR ROADHEADER SELECTION

EXCAVATION METHOD SELECTION CRITERIA

• Flexible system in terms of profile shape and size• Accurate excavation resulting in less over-break

and less concrete installation work• Low primary investment• Fast mobilization

10

CRITERIA FOR ROADHEADER SELECTION

ROCK & ROCK MASS CUTTABILITY ASSESSMENT11

GEOTECHNICAL CHARACTERIZATION

• Rock:Natural aggregate of components including minerals, rarely glasses, fragments of minerals and rocks, binding agent and X-ray amorphous substances.

• Rock mass:Combination of rock and discontinuities, separating rock into different rock bodies and forming characteristic areas of homogeneity.

12

DIFFERENTIATION BETWEEN ROCK AND ROCK MASS

REPRESENTATIVE ROCK SAMPLING

Select typical rock samples in correct quality and sufficient quantity

13

KEY SUCCESS FACTOR FOR ROCK CUTTABILITY ASSESSMENT

Block sample: 20 x 20 x 20 cm

Drill core:50 mm diameter500 mm length

Batchingcard forsampleidentification

Sample

Specimens

PRECISE LABORATORY ROCK TESTING

Rock test results representing intact rock properties

14

LEADING TO REPRESENTATIVE ROCK TEST RESULTS

USM UCS BTS CAI

INTERPRETATION OF ROCK TEST RESULTS

15

PRINCIPALLY SIMPLE, BUT VERY EFFECTICE EVALUATIONS

Rock toughness&

Fracture energy

Quick characterization of rock fracturing behavior

SUMMARY OF ROCK TEST RESULTS

16

PROVIDING CLEAR OVERVIEW OF ROCK CHARACTERISTICS

ROCK TESTINGASSESSMENT OF NCR FOR INTACT ROCK

17

0

10

20

30

40

50

60

70

80

90

100

110

120

130

140

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160

Unia

xial

Com

pres

sive

Str

engt

h [M

Pa]

Net Cutting Rate [solid m³/nch]

Net Cutting Rate for MR/MT/MH620 (300 kW installed cutter head power)equipped with Cutter Head 105-G 57+ and 22 mm TC Diameter Picks

according to Uniaxial Compressive Strength for Intact to Moderately Fractured Rock Massfor Cross Sections > 35 m²

very tough rock normal rock very brittle rock

The volume of cut rock per effective net cutting time (counted in net cutting hours ... nch) defines the netcutting rate. The effective net cutting time is defined by the time the cutter head is in contact with the rockand actually cutting. Thus, supplementary actions of the cutter head like profiling and loading or any idlingtime during cutting operation does not contribute to the effective net cuttingtime.

For calculating machine productivity or excavation performance, please consider that the ratio of machineoperating hours to net cutting hours is usually about 2:1 (ranging from 1.5:1 to 2.5:1). This difference in thetimes is caused by a number of delays and standstills (non-productive times) during cutting operation,when the machine is operated at the face.

Uniaxial Compressive Strength measured onH:D=1:1 specimen with 50 mm diameter @ 10

NCRtheor=24 solid m³/nch @UCS=100 MPa &UCS:BTS=8-15 => normal rock

ROCK TESTINGOPERATING LIMITS DEFINED BY NCR

18

Specific Pick Consumption (SPC) for Low Speed Cuttingwith Transverse Cutterhead and 22 mm TC Diameter Picks of High Quality

0,001

0,010

0,100

1,000

10,000

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180Uniaxial Compressive Strength [MPa]

Spec

ific

Pick

Con

sum

ptio

n [p

icks

/sol

id m

³]

CAI=0,5CAI=1,0CAI=1,3CAI=1,8CAI=2,3CAI=3,0CAI=4,5

Effective minimum specific pick consumption: 0,005 picks/solid m³

Uniaxial Compressive Strength measured on H:D=1:1 specimen with 50 mm diameter @ 10 kN/s

CAI ..... CERCHAR Abrasivity Index measured on rocksurface of natural roughness (e.g. surface of brokenBrazilian Tensile Strength test specimen) usingoriginal CERCHAR testing apparatus and test pickswith HRC=54-56

SPC=0.1 picks/solid m³ @UCS=100 MPa & CAI=1.0

ROCK TESTINGASSESSMENT OF SPC

19

ROCK TESTINGOPERATING LIMITS DEFINED BY SPC

20

EVALUATION OF ROCK MASS CUTTABILITY

21

USING GEOTECHNICAL REPORTS OR DOING JOB SITE INVESTIGATIONS

Mapping and recording of all relevant rock types and rock mass features/discontinuities like bedding planes, fractues, etc.

The picture can't be displayed.

EFFECT OF ROCK MASS ON CUTTING

22

PRINCIPLES OF ROCK MASS INFLUENCE ON ROADHEADER CUTTING

I

II

III

Excavation predominantly byactivation of parting planes:„RIPPING ZONE“Activation of existing parting planesand generation of new fracture planes:„INTERMEDIATE ZONE“

Excavation predominantly bygeneration of new fractureplanes: „CUTTING ZONE“

ROCK MASS CUTTABILITY RATING

23

SYSTEMATIC APPROACH FOR ROCK MASS EVALUATION

Block size [m3] Rating> 0,6 20

0,3 - 0,6 160,1 - 0,3 10

0,06 - 0,1 80,03 - 0,06 50,01 - 0,03 3

< 0,01 1

Surface Aperture Wall/Fill Rating Influence on cuttability

Rating

rough closed hard, dry 30 very favorable -12slightly rough

< 1 mm hard, dry 20 favorable -10

slightly rough

< 1 mm soft, dry 10 fair (and if block size 5 mm soft, damp to wet

0 very unfavorable 0

Rating of joint conditions Rating of orientation of joint set

100 - 200 2> 200 1

25 - 50 750 - 100 4

1 - 5 155 - 25 12

Rating of block size

UCS [MPa] Rating

Rating of uniaxial compressive strength Block Si

ROCK MASS CUTTABILITY RATING

24

FINAL RMCR SYSTEM FOR ROADHEADERS

RMRrev Influence on cuttability by roadheaders

40 - 60 no to little influence25 - 40 moderate influence15 - 25 considerable influence10 - 15 high influence

< 10 dominating influence

Block size [m3] Rating> 0,6 20

0,3 - 0,6 160,1 - 0,3 10

0,06 - 0,1 80,03 - 0,06 50,01 - 0,03 3

< 0,01 1

Surface Aperture Wall/Fill Rating Influence on cuttability

Rating

rough closed hard, dry 30 very favorable -12slightly rough

< 1 mm hard, dry 20 favorable -10

slightly rough

< 1 mm soft, dry 10 fair (and if block size 5 mm soft, damp to wet

0 very unfavorable 0

Rating of joint conditions Rating of orientation of joint set

100 - 200 2> 200 1

25 - 50 750 - 100 4

1 - 5 155 - 25 12

Rating of block size

UCS [MPa] Rating

Rating of uniaxial compressive strength

ROCK MASS CUTTABILITY RATING

25

EVALUATION OF RMCR VALUE AND ITS INFLUENCE ON NET CUTTING RATE

Evaluation of Rock Mass Influence on NCR(Low cutting speed - 1.4 m/s)

NCReff/NCRtheor = 45,553RMCR-0,9821

R2 = 0,9332

0123456789

10

0 10 20 30 40 50 60

RMCRN

CR

eff /

NC

Rth

eor

Erzberg Stillwater PozzanoPremadio Athens BilecaFresnillo Montreal

EXCAVATION STRENGTHEVALUATED AND DEFINED BY RMCR

26

Rock Mass Cuttability Rating (RMCR)Reduction of Rock Mass Strength (UCSRM) related to Rock Strength (UCSR)

for SANDVIK Roadheaders using Low Cutting Speed (~1.4 m/s)

0

50

100

150

200

250

300

0 50 100 150 200 250 300

UCSR [MPa]

UC

S RM [M

Pa]

RMCR=10RMCR=15RMCR=20RMCR=25RMCR=30RMCR=35RMCR=40RMCR=45RMCR=50

RMCR = 30

UCSR~200MPa

UCSRM~120MPa

ROCK TESTINGOPERATING LIMITS DEFINED BY RMCR

27

FACTS & DEVELOPMENTS IN DRILL & BLAST28

DRILL & BLAST CYCLE

• Hole size and round length slightly increasing• Rock supporting tasks with jumbo are becoming more important (e.g. short & long

bolt holes, self-drilling anchors, injection hole drilling & grouting, casing, installation of steel arches, rod handling)

• Multifunctional use of drilling jumbo increasing (e.g. installation works, charging, ground monitoring, profile measurement, scaling, water leakage testing)

• Faster round cycle times• Quality and cost awareness increasing• Stricter safety and environmental requirements

29

CURRENT TRENDS

DRILLING PERFORMANCENET PENETRATION RATES (M/MIN)

• Rock drillability• Percussion power level (and feed

force)• Bit diameter, type and rotation speed• Flushing• Rock drill (and impact frequency)

GROSS PENETRATION RATES (DRM/H)

• Boom moving and collaring time• Fast feed and possible anti-jamming time• Set-up time (cables, hoses and jacks)• Navigation time (Data & TCAD jumbos)• Marking of tunnel face• Cleaning tunnel floor for bottom hole

charging• Idle of booms (bit changes, repairs, etc.)

30

TUNNEL ADVANCE RATES

For one equipment set in 3-shift continuous operation

31

SINGLE OR MULTIPLE FACE OPERATION

Conditions Average advance rate (m/month)

Single heading Multiple headings

Easy - Competent rock - Minimum rock support (some

bolts)

200 - 300

300 – 450

Average - Varying rock conditions - Regular support (bolts, some

shotcrete)

150 – 250

200 – 350

Difficult - Soft & fractured rock - Heavy rock support (bolts,

shotcrete, mesh / steel arches)

< 150

100 – 200

Conditions

Average advance rate

(m/month)

Single heading

Multiple headings

Easy

· Competent rock

· Minimum rock support (some bolts)

200 - 300

300 – 450

Average

· Varying rock conditions

· Regular support (bolts, some shotcrete)

150 – 250

200 – 350

Difficult

· Soft & fractured rock

· Heavy rock support (bolts, shotcrete, mesh / steel arches)

< 150

100 – 200

ROCK BOLTING

Selection criteria referring to lifespan and cost

32

BOLT TYPES

BOLT TYPE LIFESPAN RELATIVE COST

GENERAL COMMENTS

Cement grouted rebar Permanent 1 Low cost, good availability, no immediate support

Resin grouted rebar Permanent (if fully grouted)

2 Reasonable cost, availability of resin may be problem, immediate support

Expansion shell (grouted)

Temporary / permanent (if fully grouted)

1.5 Fairly low cost, fast installation, immediate support

Cement grouted wedge-type

Temporary / permanent (if fully grouted)

1.25 Fairly low cost, fast installation, immediate support

Swellex Temporary (longer than split-set)

3 Expensive, fast installation, immediate support

Split-set (or copy) Temporary

1

Low cost, fast installation, immediate support

CT-bolt Permanent

4…5

Expensive, immediate support, good bolt properties

BOLT TYPE

LIFESPAN

RELATIVE

COST

GENERAL COMMENTS

Cement grouted rebar

Permanent

1

Low cost, good availability,

no immediate support

Resin grouted rebar

Permanent (if fully grouted)

2

Reasonable cost, availability of resin may be problem, immediate support

Expansion shell (grouted)

Temporary / permanent (if fully grouted)

1.5

Fairly low cost, fast installation, immediate support

Cement grouted wedge-type

Temporary / permanent (if fully grouted)

1.25

Fairly low cost, fast installation, immediate support

Swellex

Temporary (longer than split-set)

3

Expensive, fast installation, immediate support

Split-set (or copy)

Temporary

1

Low cost, fast installation, immediate support

CT-bolt

Permanent

4…5

Expensive, immediate support, good bolt properties

AUTOMATION FEATURES

• Possibility to drill the whole face automatically• System handles boom movements and hole drilling automatically• Hole sequences can be imported from drill plan and/or created onboard• Well-functioning hole sequences & roll-overs can be retrieved from previous

rounds (Sandvik patented feature)• Operator supervises the drilling process• Booms have self-collision avoidance

33

FULL-AUTOMATIC FACE DRILLING

SANDVIK ACCESS DETECTION SYSTEM

34

INCREASED SAFETY

Access ProtectorIf the Sandvik Access Protector system recognizes aperson in the detection field, boom and drilling movementswill automatically be stopped. In other words, the Sandvikaccess protector prevents anyone from entering theworking area of the booms while they are in operation inautomatic mode. If boom operation is automaticallystopped, the system must be reset by pressing theacknowledgement button, after ensuring that no-one is inthe hazard zone.

It’s possible to use the Access Protector as Detector –version while automatic drilling cycle is not used.

LATEST & ONGOING ROAD-HEADER DEVELOPMENTS35

EXCAVATIONCONTROLPROFILE CONTROL

36

• Profile and tunnel planning with office tool and transfer of plans to machine

• Solution fully integrated into machine control system

• Profile control

EXCAVATIONCONTROLPROFILE CONTROL

3737

• Cutter head is kept within profile limits

• Visualization of cutting process for machine operator

AUTOMATED EXCAVATIONCUTTING AUTOMATION

38

• Planning of cutting path referring to tunnel profile

• Fully automated cutting of one round length / sump distance

• Automated profiling in fast speed

TELE-REMOTE OPERATION

39

AUTONOMOUS MACHINE WITH VISUALLY SUPPORTED TELE-OPERATION

40

Thank you for your attention!!!

Breakthroughs in tunneling 2019TABLE OF CONTENTSSelection criteria for excavation methodexcavation method Selection criteriaMechanical Tunnel ExcavationRoadheader Tunnel ExcavationOverall Cutting performance too lowCutting Tool consumption too highexcavation method Selection criteriaexcavation method Selection criteriarock & rock mass cuttability assessmentGeotechnical characterizationRepresentative rock samplingPrecise laboratory rock testingInterpretation of rock test resultsSummary of rock test resultsRock testingRock testingRock testingRock testingEvaluation of rock mass cuttabilityEffect of rock mass on cuttingRock mass cuttability ratingRock mass cuttability ratingRock mass cuttability ratingexcavation strengthRock testingFacts & developments in drill & blastDrill & Blast cycleDrilling performanceTunnel advance ratesRock boltingAUTOMATION featuresSANDVIK ACCESS DETECTion SYSTEMLatest & ongoing road- header developmentsExcavation�controlExcavation�controlAutomated excavationTele-remote operationSlide Number 40