REVISION REGISTER Clause Number Description of Revision Authorised By Issue Date MME 29/06/2018 References Added WA 142.2 & WA 142.3 Table 501.02 Amended CBR criterion for Gravel Subbase 501.05 Added Sustainability Considerations Table 501.06 Amended CBR criterion for CRB Subbase Tables 501.08, 501.10, 501.13, 501.15, 501.16 Included vertical modulus criterion 501.29.04 Added trimmings clause 501.41.5 Amended Hold Point 501.46 Amended 501.47 Amended Table 501A3 Amended Basecourse Dryback (sprayed seal) criterion Table 501A8 Amended PSD criterion Guidance Notes Amended 8, 10.4, 11 & 12 Guidance Note 15 Added Note 15 for Basecourse vertical modulus Guidance Note 2.3 GER Basecourse and Sub-base specifications Guidance Note Added Note 16 for Reclaimed Pavement Whole Document Reformatted SCO 22/05/2017 501.09 Add Crushed Rock Sub-Base Material PM 22/03/2017 Table 501.11 Amended UCS criteria 501.28 Amended maximum Basecourse thickness 501.29.01, 501.30.02 & 501.30.07, 501.95.07, 501.95.11 Amended compaction moisture 501.30.08, 501.95.09 Guidance Notes 10.3 & 11.4 Amended rework requirements Guidance Note 1 Amended limitations on Ferricrete use Guidance Note 2 Add Wheatbelt Region Gravels Guidance Note 11.3 Amended Lime demand requirements Tables 501.G01, 501.G02 & 501.16 Amended design traffic limits Base
501.33 – 501.40 NOT USED 29 ACCEPTANCE 30 501.41 General 30 501.42 Compaction 30 501.43 Dryback 30 501.44 Layer Width 31 501.45 Surface 31 501.46 Surface Levels 31 501.47 Surface Finish 32 501.48 – 501.50 NOT USED 32 MAINTENANCE 32 501.51 Maintenance of Compacted Layers 32 501.52 – 501.80 NOT USED 33 AS BUILT AND HANDOVER REQUIREMENTS 33 501.81 – 501.90 NOT USED 33 CONTRACT SPECIFIC REQUIREMENTS 33 501.91 – 501.99 NOT USED 33 ANNEXURE 501 A 34 Construction Requirements 34 ANNEXURE 501 B 38 Cementitious Materials for Concrete 38 SPECIFICATION 501 PAVEMENTS GENERAL 501.01 SCOPE
The drainage layer shall consist of a Geotextile lining and a sand material of the material type and thickness as shown in Annexure 501A. The drainage layer shall be constructed immediately below the Pavement to the details shown in the drawings, and connected to a positive drainage system. 501.32.02 GEOTEXTILE The Geotextile shall be a non-woven fabric consisting of long chain synthetic polymer fibres composed of at least 85% by mass of polyesters, polyolefins or polyamides. The fibres shall be formed into a fabric by needle punching, heat or chemical bonding processes such that they are capable of retaining their relative position in the Geotextile. In addition, the fibres shall be stabilised against ultra-violet (UV) radiation and shall have low water absorbency. The Geotextile shall be free of any flaws or defects that may adversely affect the mechanical or physical properties of the fabric. Each roll of Geotextile shall be provided with a suitable covering to protect the fabric against moisture and ultra-violet radiation. Each roll shall be marked in conformance with AS 3705. Covering Rolls shall be stored on site under a waterproof cover and shall be supported off the ground. The Contractor shall take appropriate measures to protect the Geotextile from damage. Storage The Geotextile shall comply with the requirements shown in Table 501A6 and Table 501A7 of Annexure 501A. Properties All properties represent minimum roll values, that is, the test result from any sampled roll shall exceed the minimum value in Table 501A6. 501.32.03 INSTALLATION OF GEOTEXTILE The Contractor’s process of installation of the Geotextile shall ensure that fabric is not damaged. The initial lift thickness of fill materials placed directly over the Geotextile shall be a minimum uncompacted thickness of 300mm. The use of vibratory compaction equipment over the Geotextile should be minimized for the initial lift. Initial Lift Unless otherwise shown on the Drawings, the minimum overlap requirement shall be 300mm. Successive sheets of Geotextile shall be overlapped a minimum of 300mm with the upslope section overlying the down slope. Overlap The period of time between laying out and cover of the Geotextile shall not exceed 14 days. Timing Damaged areas of Geotextile may be repaired by overlaying the damaged section with a patch. The patch shall extend a minimum of 1 metre beyond the area of damage. Repairs
501.42 COMPACTION Each Pavement Layer shall be compacted to the Characteristic Dry Density Ratio shown in Annexure 501A or greater. General The Characteristic Dry Density shall be determined in accordance with Specification 201 QUALITY SYSTEMS ANNEXURE 201A 1.2.1. Characteristic Dry Density the pavement material contains more than 20% by mass of material retained on a 37.5mm sieve, the Maximum Dry Density shall be determined on that portion of the material that passes a 37.5mm sieve. Oversize Material 501.43 DRYBACK Each Pavement and the layer 150mm below the Subgrade shall be dried back such that the Dryback Characteristic Moisture Content (DMc) is equal to or less than the proportion of the Optimum Moisture Content as shown in Annexure 501A as determined by Test Method WA 133.1 or WA 133.2 as appropriate. General The Dryback Characteristic Moisture Content be determined in accordance with Specification 201 QUALITY SYSTEMS ANNEXURE 201A 1.3. Dryback Characteristic Moisture Content Where the pavement material or the material in the layer 150mm below the Subgrade contains more than 20% by mass of material retained on a 37.5mm sieve, the Optimum Moisture Content and the Maximum Dry Density shall be determined on that portion of the material that passes a 37.5mm sieve. Oversize Material 501.44 LAYER WIDTH The outer top edge of any layer of the pavement shall be no closer to the road centreline and no more than 100mm further away from the road centreline than the positions shown in the drawings. 501.45 SURFACE SHAPE 501.45.01 SUB-BASE The shape of the Sub-Base in granular Pavement shall be judged to be acceptable when the maximum deviation from a 3 metre straight edge placed in any position on the surface does not exceed 10mm. Max Deviation 10mm The shape of the Sub-Base under Full Depth Asphalt shall be judged to be acceptable when the maximum deviation from a 3 metre straight edge placed in any position on the surface does not exceed 15mm. Max Deviation 15mm Additionally, for pavement widening work, the crossfall at any position on the new surface measured at right angles to the centreline shall be within 0.5% of the existing crossfall on the outer 2 metres of the adjacent traffic lane at that location. Widening 501.45.02 BASECOURSE
Drainage Layer 94% All Sub-Base 94% Cement Stabilised Basecourse 96% Lime Stabilised Basecourse 96% Bitumen Stabilised Limestone Basecourse 98% Crushed Rock Base Basecourse 99% Hydrated Cement Treated Crushed Rock Base Basecourse 99% Other Basecourse Materials (final surfacing – sprayed seal) 96% or 98% (Select appropriate value then delete this note. Refer to Guidance Notes) Basecourse Materials (final surfacing – asphalt) 98% DRYBACK OF PAVEMENT LAYERS Pavement Layers shall be dried back to the requirements shown in Table 501A2 or Table 501A3 prior to the application of bituminous binder or the construction of the overlying layer. TABLE 501A2 DRYBACK ON SUBGRADE OR SUB-BASE LAYERS Subgrade or Pavement Layers Maximum Dryback Characteristic Moisture Content (DMc) as a proportion of Optimum Moisture Content 150mm below Subgrade surface (except for Perth sand) 85% Drainage Layer Not required Sub-Base 85% TABLE 501A3 BASECOURSE DRYBACK Basecourse Material Type Maximum Dryback Characteristic Moisture Content (DMc) as a proportion of Optimum Moisture Content