PRAC: Quality Assurance

1
PRAC Quality Assurance Control

• Mervyn Henderson

2
QA/QC Research Projects

• Deadline end July
• Battled to get input from industry
• Met in July with the Materials Testing Committee
  to finalise project definitions

3
Projects
4
Impact of Scalping on Specifications

• Introduction
• The effect of scalping the 26,5 mm fraction on
  the test results has not been sufficiently
  quantified to make adjustments to the
  specifications in the light of the change in test
  methods
• Objectives
• To determine the impact of scalping the 26,5 mm
  fraction on density, OMC, CBR and UCS test
  results with respect to the specifications
• Scope
• Different quality materials (G1 to G10, C1 to C4)
  from various origins and with fine to coarse
  gradings
• Maximum density, OMC, CBR and UCS test results
• COLTO and SABS specifications

5
Temperature Effects on Test Methods

• Introduction
• Extreme temperatures may have a significant
  effect on various pieces of equipment used for
  test methods and materials, but this had not been
  quantified.
• Objectives
• Determine suitable temperature range(s) for
  carrying out test methods
• Scope
• All commonly used test methods, especially those
  that are susceptible to temperature variation

6
Asphalt Fatigue Test Protocols

• Introduction
• There are currently equipment testing preparation
  problems with the 4 Point Beam Fatigue test (low
  temperature applicability, no commercial lab.
  apparatus available etc.)
• Objective
• To define an applicable Continuous Graded HMA
  fatigue test suitable to SADC conditions
• Scope
• To research current fatigue testing protocols and
  laboratory equipment in order to design or
  recommend user friendly applicable fatigue
  testing protocols, criteria and equipment for
  SADC conditions

7
MMLS Test Protocol

• Introduction
• The development of suitable MMLS test protocols
  and evaluation criteria are important for
  industry to gain confidence in this method of
  testing and its widespread usage for the
  characterization of asphalt mixes
• Objective
• To define applicable MMLS test protocols and
  evaluation criteria
• Scope
• To research current MMLS test protocols and to
  recommend standardized test protocols
  (temperatures / wandering / briquette preparation
  / slab preparation, etc.) for various mix types,
  in situ temperature conditions and layer types

8
Nuclear Density Apparatus

• Introduction
• Nuclear density apparatus is widely used for the
  measurement of compaction in the field. No
  nationally accepted standard exists to verify the
  results obtained from this method of measurement
• Objectives
• Devise a new national standard method for
  verifying the results of the nuclear density
  apparatus
• Scope
• A standard method is required to be developed
  into a national standard

9
Limits for the Repeatability, Reproducibility and
Precision of TMH1 Test Methods

• Introduction
• The current transformation of TMH1 test methods
  to new SANS test methods requires the provision
  of information to define the repeatability,
  reproducibility and precision of the test
  methods.
• There are also different interpretations of the
  terms and limits for different materials and test
  methods.

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Limits for the Repeatability, Reproducibility and
Precision of TMH1 Test Methods

• OBJECTIVES
• Determine and clearly define what controls should
  be used
• Determine for which tests such controls can be
  put in place
• Collect and analyse existing data gathered from
  industry over the last thirty years covering
  repeatability and inter-laboratory comparisons
• Supplement existing work with additional testing
  where such data is lacking
• Set up applicable national limits.
• Educate all sectors of the industry

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Limits for the Repeatability, Reproducibility and
Precision of TMH1 Test Methods

• Scope
• All TMH1 test methods, starting with the most
  important and popular tests first including tests
  used by accredited laboratories