Increased agility for the research and development

of dynamic roof support products

Greig Knox&

Adrian Berghorst

© NCM 2018

© Copyright 2018 Innovative Mining Products (Pty) Ltd t/a New Concept Mining ("NCM"). All rights reserved. This document is confidential and may not be reproduced or shared without the express written permission of NCM.

Agenda

• Dynamic Performance• Dynamic Test Methods• NCM DIT Overview & Instrumentation• Data Processing

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PresenterPresentation NotesDynamic PerformanceExpected performance versus actual performance

Test MethodsTwo of the well known methods

Overview of the NCM DIT

Data Processing

Requirement for Dynamic Testing

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PresenterPresentation NotesIncrease in the depth of minesRock bursts – strain burstSeismicityDifference in performance Stiff BoltYielding BoltDynamic BoltDynamic Increase Factor Malvar and CrawfordFirst Dynamic TestSouth Africa Ortlepp & Stacey

Requirement for Dynamic Testing

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PresenterPresentation NotesIncrease in the depth of minesRock burstsSeismicityDifference in performance Stiff BoltYielding BoltDynamic BoltDynamic Increase Factor Malvar and CrawfordFirst Dynamic TestSouth Africa Ortlepp & Stacey

Test Methodologies

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PresenterPresentation NotesCanMETCanadianImpact test methodOriginally developed for testing landing gear on space shuttle

WASMAustralianMomentum transfer method Developed to be able to perform full system tests

Drop Test Facility for R&D

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PresenterPresentation NotesLimitation of Drop test method:Purely axial loading – No ShearNot a complete simulation of underground conditions

Advantages:Repeatable / consistentRelatively safeRelatively cost effective

Provides a platform on which revisions / products and be compared

NCM DIT

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PresenterPresentation NotesVideo overview of the NCM DIT

Sample loaded through the bore of the trolleyKnown mass raised to a known height Release of trolley potential energy converted to kinetic energy Impact – force and displacement result of work done to absorb the energy

NCM DIT

• 65 kJ Energy (maximum)

• 551kg Weight (minimum)

• 3171kg Weight (maximum)

• 2.1m Drop Height (maximum)

• 6.4m/s Velocity at Impact (maximum)

• 3.5m Bolt Length (maximum)

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PresenterPresentation NotesOverview of the system specification

NCM DIT: Measurement Overview

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PresenterPresentation NotesTypical ResultImpact loadPlate load Proximal DisplacementDistal Displacement

Additional Load Cell Set frame load cell

NCM DIT: Measurement OverviewLoad Cells

Line scan Cameras

User Interface & Report Generation

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PresenterPresentation NotesOverview of outcome measurements – a large number of other sensors running to ensure health and safe operation of the machine

Piezoelectric load cells 3 setsLine scan camera’s used from displacement measurementAutomatic calculation of displacement measurementLighting requirement X axis displacement / Y axis time

Ability to automatically view data and generate reports

Importance of sample preparation

NCM DIT: Data Processing

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PresenterPresentation NotesIsolate Focus on the first impulse of multiple

NCM DIT: Data Processing

215 Samples500 Drops

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Thank youQuestions ?

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ReferencesAnderson, B. V. (2015). Dynamic Behaviour of New Concept Mining PAR1 Bolt.Hadjigeorgiou, J., & Yves, P. (2011). A Critical Assessment of Dynamic Rock

Reinforcement and Support Testing Facilities. Rock mechanics and rock engineering 44, no. 5, 565-578.

Ortlepp, W. (1969). An Empirical Determination of the Effectiveness of RockboltSupport under Impulse Loading. Proceedings of the International Symposium on Large Permanent Underground Openings, (pp. 197-205). Oslo.

Villaescusa, E., Thompson, A., & Player, J. (2004). Dynamic Testing of Rock Reinforcement using the Momentum Transfer Method. Fifth International Sysmposium on Ground Support in Mining and Underground Construction, (pp. 237-339). Perth.

© NCM 2018

Slide Number 1AgendaRequirement for Dynamic TestingRequirement for Dynamic TestingTest MethodologiesDrop Test Facility for R&DNCM DITNCM DITNCM DIT: Measurement OverviewNCM DIT: Measurement OverviewNCM DIT: Data ProcessingNCM DIT: Data ProcessingThank you�Questions ?Slide Number 14