Aggregates. Jason Jones Les Millar. #14 Aggregates Jason Jones & Les Millar 1

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1 Aggregates Jason Jones Les Millar #14 Aggregates Jason Jones & Les Millar 1

2 Aggregate Specifications and Technical Standards MRS22, MRTS 22 and Annexure MRTS22.1 Supply of Cover Aggregate MRS30, MRTS 30 and Annexure MRTS30.1 Dense Graded and Open Graded Asphalt MRS31, MRTS 31 and Annexure MRTS Heavy Duty Asphalt #14 Aggregates Jason Jones & Les Millar 2

3 Overview Draft specifications released by TMR late December 2007 The following current bituminous specifications reference aggregates MRS11.22, MRS11.30, MRS11.34, MRS11.36, (MDSS548) Other specifications (granular and concrete) also have references to quarry material TMR proposed that a single Pavement Aggregates specification/technical standard be developed AAPA supports this direction Cement Concrete & Aggregates Australia (CCAA) have been involved in discussions and these are continuing Due to time constraints, a separate Pavement Aggregates standard not developed, aggregate property requirements remain in the separate technical standards #14 Aggregates Jason Jones & Les Millar 3

4 MRS 22 Supply of Cover Aggregate The content in the draft MRS22 does not significantly differ from the relevant sections of the current MRS11.22 One difference is standard item number 5012 Supply of Cover Aggregate has a changed unit of measurement from tonnes to m 3 #14 Aggregates Jason Jones & Les Millar 4

5 MRTS 22 Supply of Cover Aggregate Addition of aggregate properties requirements to include ALD, PAFV, Degradation Factor and Water Absorption Hold point 2, precoating procedure, to be changed to a witness point Crushed Particles testing will not be required on material from a blasted face in a quarry Wet/dry strength variation for aggregate quality A has changed to maximum 35% (from 30%) #14 Aggregates Jason Jones & Les Millar 5

6 MRTS 22 Supply of Cover Aggregate Degree of Aggregate Precoating has changed from minimum 85% to minimum 70% Time period between precoating and spreading has been moved from Annexure MRS into the main body of MRTS22 (table 7.1.4). Time period specified as: 7 28 days (agent without waste oil) days (agent containing waste oil) Administrator may approve use outside these nominated periods if the result from a stripping test shows less than 10% strip AAPA requested a reduction to the minimum days and removal of the requirement for maximum days. This was not accepted by TMR #14 Aggregates Jason Jones & Les Millar 6

7 MRTS 22 Supply of Cover Aggregate Lot sizes and testing frequencies have been moved from Annexure MRS MRTS30 for aggregate strength and durability tests Table 8.2 of MRTS22 for PSD, FI and ALD Normal, reduced and tightened frequencies have been provided A complying aggregate lot within a quarry can be used to supply a number of different projects Australian Standard test methods will be allowed only when the AS test method is the same as the specified Q test method #14 Aggregates Jason Jones & Les Millar 7

8 MRTS 30 DG & OG Asphalt Coarse aggregate properties DG asphalt have not changed OG asphalt have tightened New properties for fine aggregate Source rock of fine aggregate to comply with the values set for coarse aggregate for the following properties Ten percent fine value (wet) Wet/dry strength variation Degradation factor No properties currently specified in MRS11.30 & 34 Properties align with existing heavy duty asphalt specification #14 Aggregates Jason Jones & Les Millar 8

9 MRTS 31 Heavy Duty Asphalt MRTS31 will become the base heavy duty asphalt technical standard MRSS , TS31 and PSTS31 will be withdrawn Aggregate properties for MRTS31 are the same as MRTS30. The aggregate standards will be less stringent than those currently specified for heavy duty asphalt #14 Aggregates Jason Jones & Les Millar 9

10 PAFV Requirements Provision has been made in Annexure MRTS30.1 and Annexure MRTS22.1 for the Principal / Designer to select minimum PAFV for coarse aggregate Until the Main Roads policy on macrotexture and microtexture is released, the minimum PAFV value will be 48 for open graded asphalt (MRTS30) 48 for DG14HS surfacing layers (MRTS31) 45 for other dense graded surfacing layers (MRTS30) No requirement for cover aggregate (MRTS22) #14 Aggregates Jason Jones & Les Millar 10

11 Aggregate Testing TMR concerns: Quality / durability Safety / Polishing Testing will provide assurance to TMR that aggregates supplied to projects comply with technical standard requirements #14 Aggregates Jason Jones & Les Millar 11

12 Aggregate Testing Coarse aggregate testing frequencies included in main body of MRTS30 No requirement in MRS11.30 & MRS11.34 to test aggregates Testing frequencies are currently covered in Appendix K of the Asphalt Supplier Registration System Reduced testing frequencies compared to existing heavy duty asphalt supplementary specification Testing of fine aggregate source rock is only required when it s obtained from a different source to the coarse aggregate. Testing only required for the following properties Ten percent fines value (wet) Wet/dry strength variation Degradation factor #14 Aggregates Jason Jones & Les Millar 12

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14 Estimated Testing Frequencies Property Frequency of Testing per Lane km (3.5 m Lane) 50 mm DG14 Layer Normal Reduced Flakiness Index 1/ 10 km 1 / 19 km 10% Fines (wet) 1 / 39 km 1 / 77 km Wet/dry Variation 1 / 39 km 1 / 77 km Weak particles 1 / 10 km 1 / 19 km Water absorption 1 / 39 km 1 / 77 km Deg. Factor 1 / 39 km 1 / 77 km Surfacing Layer Only PAFV 1 / 39 km 1 / 77 km PAFV (marginal compliance) 1 / 10 km 1 / 19 km #14 Aggregates Jason Jones & Les Millar 14

15 Aggregate Testing TMR estimate of testing costs: Normal testing frequency $0.40 / tonne Reduced testing frequency $0.20 / tonne #14 Aggregates Jason Jones & Les Millar 15

16 Summary Aggregate properties have changed as follows: Dense graded largely unchanged Open graded more stringent requirements Heavy duty less stringent requirements Aggregate compliance testing has been embedded in the cover aggregate and asphalt specifications There is agreement to move pavement aggregate requirements to a separate technical standard in the future Statistical based assessment of aggregate properties will be part of ongoing discussions between TMR, AAPA and CCAA Changes to the technical standards may lead to some quarries, currently supplying material for sealing and asphalt to no longer be able to supply aggregates for these applications #14 Aggregates Jason Jones & Les Millar 16