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FEEDBACK ON SANRAL / SAACE /SAFCEC WORKSHOP ON LABORATORY ACCREDITATION & MANAGEMENT Held on 28 MARCH 2003
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings MANAGEMENT OF SITE LABORATORIES – Wesley Weber SANAS ACCREDITATION – Rob Damhuis Main Laboratory Site Laboratory – temporary accreditation COMBINED LABORATORY PROPOSAL – Johan Gillmer (Acceptance and Process Control) COMBINED LABORATORIES: - Poens Venter The Contractors’ Perspective
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SANAS ACCREDITATION Main Laboratory Site Laboratory – temporary accreditation INTERLAB CORRELATION Binders C ement stabilisation: new findings NATIONAL PROFICIENCY TESTING INTRODUCTION MANAGEMENT OF SITE LABORATORIES STANDARDISATION OF TEST METHODS – Barry Dumas COMBINED LABORATORY PROPOSAL (Acceptance and Process Control) COMBINED LABORATORIES: The Contractors’ Perspective
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MTC is responsible for the Standard Test Methods regarding: Evaluation Upgrading Publishing
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http://Asphalt.CSIR.co.za/tmh
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Although the members of MTC are mainly from the Road Authorities the industry is nevertheless invited to partake in the process of upgrading the Standard Test Methods. All recommendations can be addressed to: Although the members of MTC are mainly from the Road Authorities the industry is nevertheless invited to partake in the process of upgrading the Standard Test Methods. All recommendations can be addressed to: MTC The Secretariat Fax: 021 - 483-3620
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas
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Proficiency testing continues to be the best mechanism for ensuring that laboratory tests are being performed properly. This is also applicable to accredited laboratories, because proficiency testing on accredited laboratory tests is a vital component of the laboratory’s quality assurance program. Proficiency testing is a good risk management tool for the laboratory and provides confidence in the correctness of the results obtained.
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Precision A generic concept related to the closeness of agreement between test results obtained under prescribed like conditions from the measurement process being evaluated.
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Data Representation Dry Density vs Moisture Content relationship ASTM D1557 :– “plot the values and draw the compaction curve as a smooth curve through the points”.
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Data Representation CBR vs Dry Density relationship ASTM D1883 :– “plot the values and draw the compaction curve as a smooth curve through the points”.
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CBR vs Compaction Compaction (%) CBR Compaction (%) CBR Compaction (%) CBR Compaction (%) CBR Compaction (%) CBR
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings
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SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation Inter-Laboratory Correlation Testing of Binders Curing of Cement Stabilized Laboratory Samples By Russell Clayton Ninham Shand Consulting
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SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation Binder Testing 3 BINDERS 60-70 penetration grade 80-100 penetration grade Class SE-1 (RMB3) 2 TESTS Softening point Penetration TEST CONDITIONS Normal test procedure After 48hrs ageing in fridge
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SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation TESTER EXPERIENCE ON SOFTENING POINT Test Results not affected by : Age Years Testing Experience Education and Tertiary Training Industry Training Test Results affected by : Years Binder Testing Experience Younger (less experienced testers have more erratic results)
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TESTER EXPERIENCE ON PENETRATION No correlation could be determined by the following : Age Years Testing Experience Years Binder Testing Experience Education and Tertiary Training Industry Training SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation
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Curing of Cement Stabilized Laboratory Samples Reasons for the Investigation Cement specification and behavior has changed Problems were being experienced with compaction Contractors being asked to rework material and re-dose with cement because of low 24hrs UCS strengths Some doubt regarding the appropriate laboratory design curing procedures SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation
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CONCLUSIONS The 24 hrs curing under estimates the 7 day strengths The 40 hrs curing predicts closer 7day UCS strengths Higher ITS results are achieved with 40hrs curing but not as close to 7day strengths Not shown.. But the same response has occurred with blends of crushed dolerite or sandstone,weathered dolerite and sandstone ROC SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation
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CONCERNS Long term strengths of 4.5MPa UCS are being achieved at 90days for a C3 material..is this correct Long term strengths of 500kPa ITS are being achieved at 90days for a C3 material..is this also correct Stabilizer contents are being recommended on 24hrs curing. In the long term, over stabilization and cracking is likely to occur Does our mechanistic analysis procedures consider this ? We may be wasting money by over-dosing with cement SANRAL /SAACE/SAFCEC Workshop on Laboratory Accreditation
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings MANAGEMENT OF SITE LABORATORIES – Wesley Weber
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CONSTRUCION MATERIALS AND MANAGEMENT OF LABORATORIES CONTENTS: Responsibility of Laboratory Responsibility for Quality Control Quality Assurance Responsibility of the Engineer Responsibility and duties of Materials Supervisory Staff Materials Staff Requirements and Training
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings MANAGEMENT OF SITE LABORATORIES – Wesley Weber SANAS ACCREDITATION – Rob Damhuis Main Laboratory Site Laboratory – temporary accreditation
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Agenda 1.Overview of SANAS 2.Accreditation of Base (main) labs to SABS ISO/IEC 17025 3.Accreditation of Site laboratories (SANAS R52-1 document)
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings MANAGEMENT OF SITE LABORATORIES – Wesley Weber SANAS ACCREDITATION – Rob Damhuis Main Laboratory Site Laboratory – temporary accreditation COMBINED LABORATORY PROPOSAL – Johan Gillmer (Acceptance and Process Control)
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COMBINED LABORATORY PROPOSAL Presented by : Johan Gillmer 28 March 2003
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1. CONTRACTUAL OBLIGATIONS COMBINED LABORATORY PROPOSAL CONTENTS OF PRESENTATION 2. HISTORY OF TESTING 3. COMBINED LABORATORY SPECIFICATION 3.1 Objectives 3.2 Contents 4. CASE STUDY 4.1 Procedural data 4.2 Monthly / accumulative cost to the contractor 4.3 Monthly / accumulative cost to the employer 5. CONCLUSION
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COMBINED LABORATORY PROPOSAL CONCLUSION The choice of a test laboratory remains with the contractor. 1. REGARDED AS A FAIR SPECIFICATION FOR THE FOLLOWING REASONS : The contribution of the contractor to the employer’s cost of having a site laboratory can be determined and is related to the actual process control testing required. The employer is compensated for the additional cost to work outside normal working hours. The system offers an incentive to the well organised and competent contractor who works according to a structured quality assurance system and produces work of quality.
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COMBINED LABORATORY PROPOSAL CONCLUSION (continued) Feed back from employer / contractors / consultants should be addressed. Overtime classification should be clearly defined. Unit rates for testing (Schedule A) of samples should be market related. Hourly rates (Schedule B) of lab staff should be related to the consultants team for the specific site. The determination of the value of the approved contractors staff and equipment should be clearly defined. 2. REFINENMENT OF SPECIFICATION
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INTRODUCTION STANDARDISATION OF TEST METHODS – Barry Dumas NATIONAL PROFICIENCY TESTING – Barry Dumas INTERLAB CORRELATION – Russell Clayton Binders C ement stabilisation: new findings MANAGEMENT OF SITE LABORATORIES – Wesley Weber SANAS ACCREDITATION – Rob Damhuis Main Laboratory Site Laboratory – temporary accreditation COMBINED LABORATORY PROPOSAL – Johan Gillmer (Acceptance and Process Control) COMBINED LABORATORIES: - Poens Venter The Contractors’ Perspective
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Payment for overtime worked by laboratory staff Consistency of testing Expensive laboratory assistants in stead of training local people Tariffs – where the Contractor has to pay for each process control test ISSUES
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Control/management of laboratories not good. Contractors are not tendering on equal grounds Assistance to Contractor with: - –Testing of Materials from Commercial Sources –Finding Borrow Pits/Exploratory Testing –Process Experiments, e.g. Compaction effort
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RECOMMENDATIONS The Employer and the Engineer should accept that a combined laboratory has a responsibility to ensure that the Contractor’s obligations to test in terms of COLTO98 are fully complied with. (Duty of Care) The management and control of the combined laboratory should be shared between the Engineer and the Contractor. Contributions to combined laboratories should be standardised to ensure that Contractors tender on an equal basis and to avoid confusion and ambiguity.
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RECOMMENDATIONS Shifts should be introduced to overcome the issue of overtime and work outside of normal working hours. SANRAL should consider appointing independent laboratories on site. This would improve relationships on site and would reduce conflict situations even further. Contractors would also have more faith that the laboratory would be unbiased.
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RECOMMENDATIONS Alternatively, SANRAL could call for tenders from commercial laboratories to perform process, quality and acceptance control testing on sites in a combined laboratory arrangement and then include the cost of the total service in the tender documents to which the Contractor would contribute.
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