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1

Proposed training program for shotcrete operators

To achieve a quality shotcrete system



2

Introduction

• Australian shotcrete industry• Advantages of a training program• Proposed training program• Case Studies• Recommendations• Conclusions



3

Austrlain Shotcrete Industry

• Australian Mining industry uses approximately 500,000 cubic meters of shotcrete per year

• Mines want 32 to 40 MPa UCS (Unconfined Compressive Strength) at a minimum thickness of 50 mm and a cost of $650 to $750 per cubic metre

• Quality and cost is significantly affected by the skill and knowledge of the shotcrete operator

• Australia does not have an accredited shotcrete operator training program



4

Advantages of a Training Program

• The aims of a nationally recognised and standardised training program are to– Achieve a consistent quality of shotcrete – Ensure safe and rapid development– Recognition of employee’s skills– Transferable skills– Safer mining



5

Proposed Training Program

• Level 1. Trainee shotcrete operator• Level 2. Pump operator• Level 3. Nozzle operator• Level 4. Advanced nozzle operator (or

trainer-assessor)• Level 5. Project manager



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Training Program - Content• Level 1 - trainee shotcrete operator

De scripti on Est imat ed Ti me

Schedule d Com pletion

Ov ervi ew of training progr am 2 hours W eek 1

QMITA B ge neri c me talliferrous core induction progr am 10 hours W eek 1

QMITA B ge neri c me talliferrous elective induction program 5 hours W eek 1

Introduction to shotcrete an d illustrated glossary 2 hours W eek 2

Und erground communi cation 2 ho urs W eek 2

Plan an d organise individual work 2 hours W eek 2

Hazar d identification and risk assessment 3 hours W eek 2

Site induction 30 hours W eek 3

Site light vehicle ticket (equip ment manual) 10 hours W eek 4

Concret e basics , including fibre 3 hours W eek 5

Batch plant o perato r (theory and quality control) 3 hours W eek 6

Site agitator ticket (equipmen t manual, for mal training component) 30 hours W eek 7

Shotcret e Rig (equipment manua l, formal training com ponent) 40 hours W eek 8

Maintenan ce an d mino r repairs 10 hours W eek 9

Consolidation of skills and allowa nce for scheduling 30 hours W eeks 10 , 11 & 12



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Training Program - Content• Level 2 - pump operator

Description Estimated Time

Scheduled Completion

Job safety analysis 3 hours Week 1

Crew communication 3 hours Week 1

Introduction to ground prepa ration 10 hours Week 2 & 3

Maintenance trouble shooting 10 hours Week 4 & 5

Electrical and hydraulic trouble shooting 10 hours Week 6 & 7

Mix trouble shooting 10 hours Week 8 & 9

Factors affecting mix performance 5 hours Week 10

Fibre balls 2 hours Week 11

Extra water 2 hours Week 12

Oversize aggregate 2 hours Week 13

Admixtures and dosages 5 hours Week 14

Quality implications 5 hours Week 15

Rejection of loads 5 hours Week 16



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Level 3 – nozzle operator

Training Program - Content

De s cripti o n Est imat e d Ti m e

Sc h ed ule d C om pletion

Supplier c o mmuni c ation 5 hours W eek 1

Site specifi c ground aw are n ess course 10 hours W eek 1

Australian Standard s in testing 10 hours W eeks 3 & 4

Certification to sp ray test panels 30 hours W eeks 5 & 6

L og o f fifty test p anels to r equired stand a rd 40 hours W eeks 7 to 11

Und e rstanding of tensile strength 5 hours W eek 12

Flexural strength 5 hours W eek 13

Shea r strength 5 hours W eek 14

Bond strength 5 hours W eek 15

De v elop standard o p erating pro c edures 5 hours W eeks 16 to 19

Senior first aid c ertificate 15 hours W eek 19

Adva n ced admixtures and dosages 5 hours W eek 20

Practi c al application of stabilizers 5 hours W eek 21

Practi c al application of ac c elerator 5 hours W eek 22

Practi c al application of w at e r redu c er 5 hours W eek 23

Calculations of dosag e rates by w eight of ce m entatious mat e rial

10 hours W eeks 24 & 25

Justifying rejection of loads 5 hours W eek 26

Limits o f a d mixture quantities 5 hours W eek 27

Consolidation of skills 40 hours W eeks 28 to 36



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• Level 4 - advanced nozzle operator




Supervisory communication 10 hours Weeks 1 to 4

Leadership and motivation 10 hours Weeks 5 to 8

Introduction to contract management 10 hours Weeks 9 & 10

Supervisor for up to 24 hour, 7 day operation 40 hours Weeks 11 & 12

Parts of Certificate IV Workplace Training and Assessment 30 hours Weeks 13 to 24

Consistent procedures (quality control) 15 hours Weeks 25 to 28

Implement and maintain standards on site 10 hours Weeks 29 to 32

Consolidation of skills 10 hours Weeks 33 to 36



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• Level 5 – project manager




Client communication 10 hours Weeks 1 to 4

Advanced contract administration 10 hours Weeks 1 to 4

Advanced site administration procedures 10 hours Weeks 5 to 8

Consistent procedures across all sites 10 hours Weeks 9 to 12

Supervisory level in charge of a 24/7 operation with 4 crews

10 hours Weeks 13 to 16

Hiring procedures 10 hours Weeks 17 to 20

Retrenchment procedures 10 hours Weeks 21 to 24



11

Assessments

• Confirm Learning Outcomes• Accredited Assessor• Competency Standards• Elements• Performance Criteria• Statement of Attainment• Australian Qualification Framework



12

NorthParkesKey PointsKey Points::

••500m high block cave500m high block cave••8 extraction drives 8 extraction drives ••142 draw points142 draw points



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NorthParkes Issues• Inexperienced staff

• Experienced staff moving on to mining crews• Training was limited to what the operators could pick up in a

two week handover• Poor practices were being passed on as standard work

procedures• Shotcrete was transferred underground from a large agitator to

a smaller more manoeuvrable rig underground via a slick line.• Excessive rework to rectify poor shotcrete• Shotcrete was not meeting the required specifications



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Improved Core UCSSPRAYED

0

5

10

15

20

25

30 35 40 45 50 55 60 65 70 75

UCS(MPa)

NO

OF

EVEN

TS

Before training After training



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Improved Core ResultsBATCH-SPRAYED UCS

0%10%20%30%40%50%60%70%80%90%

100%

30 35 40 45 50 55 60 65 70 75 80 85 90 90+

UCS-MPa

%

sprayed (BT) batched (BT) sprayed(AT) batched(AT)



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Improved In-situ Density In-situ Density

0

10

20

30

40

50

2200 2250 2300 2350 2400 2450 2500

Density (kg/m3)

No

of E

vent

s

Before Training After Training



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20 % Improvement in Accelerator Dosage

ACCELERATOR USAGE

0.0

20.0

40.0

60.0

80.0

100.0

19 20 21 22 23 24 25 26 27 28

lt/m3

%

BEFORE TRAINING AFTER TRAINING



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Depth Probing



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Peak Gold Mine

• Restarting shotcrete system• Shotcrete operators came back from

months in other roles • Temporary batch plant operated by

contractor



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Peak Results• Increase in UCS from 32.5 to 35 MPa (7.6%)• A saving in excess of 40 litres per heading in accelerator

usage• There was a improvement in the quality of the shotcrete

applied underground• There was a improvement in the performance of the

shotcrete operator’s• Improved operator understanding of the use and control of

the Maxijet including concrete pump speed and pressure, accelerator pump setting and engine speed setting



21

Recommendations

• Initial audit• Collect data• Review existing procedures• Analyse training needs• Monitor the shotcrete and training

systems• Seek continuous improvement



22

Conclusions• Training has a significant and immediate impact

on the performance of a mine’s shotcrete system.• Monitoring the shotcrete systems performance is

an essential element of, monitoring the effectiveness of training and reducing the cost of shotcrete.

• Training is an essential step to developing and improving a quality shotcrete system.



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