Sprayed Seal Manual 443_AP-T17

AP-T17

AUSTROADS

PRACTITIONERS GUIDE TO DESIGN OF SPRAYED SEALS REVISION 2000 METHOD

Practitioners Guide to Design of Sprayed Seals Revision 2000 Method

First Published 2002

Austroads Inc. 2002

This work is copyright. Apart from any use as permitted under the Copyright Act 1968, no part may be reproduced by any process without the prior written permission of Austroads.

National Library of Australia Cataloguing-in-Publication data:

Practitioners Guide to Design of Sprayed Seals Revision 2000 Method ISBN 0 85588 621 8

Austroads Project No. T&E.P.N.513

Austroads Publication No. APT17 /02

Project Manager Mr Lance Midgley, VicRoads

Working Group

Mr R Gaughan, RTA NSW (Convenor) Mr W Holtrop, AAPA

Mr I Cossens, VicRoads Mr S Hogan, DMR Qld

Mr K Neaylon, TSA Mr B Walker, DIER Tas

Mr J Rebbechi, formerly CSR Emoleum Dr J Oliver, ARRB TR Mr S Brown, VicRoads

Mr A Alderson, ARRB TR (Technical Secretary)

Published by Austroads Incorporated Level 9, Robell House 287 Elizabeth Street

Sydney NSW 2000 Australia Phone: +61 2 9264 7088

Fax: +61 2 9264 1657 Email: [email protected]

www.Austroads.com.au

Austroads believes this publication to be correct at the time of printing and does not accept responsibility for any consequences arising from the use of information herein. Readers should rely on their own skill and

judgement to apply information to particular issues.

PRACTITIONERS GUIDE TO DESIGN OF SPRAYED SEALS

REVISION 2000 METHOD

Sydney 2002

AUSTROADS PROFILE

Austroads is the association of Australian and New Zealand road transport and traffic authorities whose purpose is to contribute to the achievement of improved Australian and New Zealand transport related outcomes by: developing and promoting best practice for the safe and effective management and use of the road

system providing professional support and advice to member organisations and national and international

bodies acting as a common vehicle for national and international action fulfilling the role of the Australian Transport Councils Road Modal Group undertaking performance assessment and development of Australian and New Zealand standards developing and managing the National Strategic Research Program for roads and their use. Within this ambit, Austroads aims to provide strategic direction for the integrated development, management and operation of the Australian and New Zealand road system through the promotion of national uniformity and harmony, elimination of unnecessary duplication, and the identification and application of world best practice.

AUSTROADS MEMBERSHIP

Austroads membership comprises the six State and two Territory road transport and traffic authorities and the Commonwealth Department of Transport and Regional Services in Australia, the Australian Local Government Association and Transit New Zealand. It is governed by a council consisting of the chief executive officer (or an alternative senior executive officer) of each of its eleven member organisations: Roads and Traffic Authority New South Wales Roads Corporation Victoria Department of Main Roads Queensland Main Roads Western Australia Transport South Australia Department of Infrastructure, Energy and Resources Tasmania Department of Infrastructure, Planning and Environment Northern Territory Department of Urban Services Australian Capital Territory Commonwealth Department of Transport and Regional Services Australian Local Government Association Transit New Zealand The success of Austroads is derived from the synergies of interest and participation of member organisations and others in the road industry.

A U S T R O A D S 2 0 0 2 i

PREFACE

This document is a summary of the Austroads Provisional Seal Design Method Revision 2000 (AP-T09) June, 2000. It has been prepared to provide a convenient guide to practitioners.

This Design Method has been prepared for use in conjunction with the NAASRA Technical Report Bituminous Surfacing - Sprayed Work (NAASRA 1989), and replaces the design procedures in Section 3.3.3 - Aggregate Application Rate and Section 3.3.5 - Binder Application Rate of that document. This Design Procedure also replaces the Austroads document Design of Sprayed Seals (Austroads 1990).

Multipliers for the binder application rates of Polymer Modified Binders (PMBs) and Bitumen Emulsion Binders (hereafter referred to as emulsions) and their aggregate spread rates are included. Also refer to the Austroads AP-T04 and Guidelines for the Selection and Use of PMBs and the Bitumen Emulsion Users Guide.

INTRODUCTION

This method has been produced as the result of an Austroads review involving 47 sealing trials and extensive monitoring work. The road trials compared the Austroads (1990), the local State Road Authority (SRA) and modified National Institute for Transport and Road Research (NITRR) South Africa design methods for use in Australia. As a result of this study, two approaches to seal design were considered based on (1) a statistical analysis of field and laboratory data, and (2) consensus of experienced practitioners based on the trial results.

This Revision 2000 seal design method, based upon consensus, is considered to be a step forward and it is released as a provisional update of the 1990 Austroads Design of Sprayed Seals document. This method is expected to be further reviewed when the results of subsequent validation trials can be assessed and incorporated into a final seal design method, and it is expected this will be possible by 2002/2003.

It is expected that the final method will be a combination and consolidation of the two approaches to ensure the most favourable and practical outcome. The method based upon the statistical approach is presently being fully validated by field performance trials.

Designers should also continue to apply their own judgement based on proven performance, and take into account local practices and procedures, to design binder application rates. It is requested that feedback be provided to Austroads on any anomalies observed with regard to the Provisional Design Method given in this document.

This design procedure document describes the design rates of application for various seals and reseals in three parts as follows:

PART I Size 10 mm and Larger Aggregates PART II Size 7 mm and Smaller Aggregates PART III Double/Double seals.

Typical examples of designs, applications and calculations are shown in Appendix 1.

For the purpose of this document, where general references are made to typical traffic volumes, the following descriptions apply: very low (< 200 vehicles per lane per day), low (201-750 v/l/d), medium to high (751-2000 v/l/d) and high (> 2000 v/l/d).

CONTENTS

PART I Size 10 MM and Larger Aggregates ................................................................1

1. Introduction .............................................................................................................1 1.1 Assumptions ..........................................................................................................................................1 1.2 Design Philosophy (Basis for method) ..................................................................................................2

2. Aggregate Spread Rate ..........................................................................................3 2.1 Conventional binder...............................................................................................................................3 2.2 Very Low Traffic Roads .........................................................................................................................3 2.3 Polymer Modified Binders (PMBs) ........................................................................................................4 2.4 Bitumen Emulsion Binders ....................................................................................................................4

3. Binder Application Rate for Single/Single seals ..................................................5 3.1 General ..................................................................................................................................................5 3.2 Factors Affecting the Binder Application Rates.....................................................................................5

4. Basic Voids Factor (Vf) ...........................................................................................7

5. Adjustments ............................................................................................................8 5.1 General ..................................................................................................................................................8 5.2 Aggregate Adjustment (Va)....................................................................................................................8 5.3 Adjustment for Traffic Effects (Vt) ..........................................................................................................8

6. Basic Binder Application Rate (BB) .....................................................................10

7. Allowances ............................................................................................................11 7.1 Texture Allowance (AS)........................................................................................................................11

7.1.1 Retreatment of Existing Seals .............................................................................................................. 11 7.1.2 Resealing over Asphalt......................................................................................................................... 11 7.1.3 Resealing over Slurry Surfacing .......................................................................................................... 11 7.1.4 Resealing over Primed Concrete Surfaces........................................................................................... 12 7.1.5 Resealing over Timber Surfaces .......................................................................................................... 12 7.1.6 Sealing Treatments............................................................................................................................... 12

7.2 Binder Absorption Allowance (ABA)......................................................................................................12 7.2.1 Binder Absorption by Aggregate.......................................................................................................... 12 7.2.2 Binder Absorption by Pavement .......................................................................................................... 13

7.3 Embedment Allowance (AE) ................................................................................................................15 7.3.1 Seals ..................................................................................................................................................... 15 7.3.2 Reseals ................................................................................................................................................. 16

8. Design Binder Application Rate (BD)...................................................................17 8.1 Conventional Binders ..........................................................................................................................17 8.2 Emulsion Binders.................................................................................................................................17 8.3 Polymer Modified Binders (PMBs) ......................................................................................................18

CONTENTS (continued)

PART II SIZE 7 MM and SMALLER AGGREGATES...................................................19

9. Design Application Rates for Size 7 MM and Smaller Aggregates ...................19 9.1 General ................................................................................................................................................19 9.2 Aggregate Spread Rate.......................................................................................................................19 9.3 Binder Application Rates .....................................................................................................................20

9.3.1 Information Required........................................................................................................................... 20 9.3.2 Basic Binder Application Rate (BB) ..................................................................................................... 20 9.3.3 Design Binder Application Rate (BD)................................................................................................... 20

PART III DOUBLE/DOUBLE SEALS ...........................................................................23

10. Design Application Rates For Double/Double seals ..........................................23 10.1 General ................................................................................................................................................23 10.2 Both Applications on the Same Day....................................................................................................23 10.3 For the Second Application Delayed ...................................................................................................24

REFERENCES ..................................................................................................................25

APPENDIX 1 SEAL DESIGN EXAMPLES ...................................................................26

General .............................................................................................................................26

Example 1 Single/Single reseal..................................................................................26 Job details.........................................................................................................................................................26 Traffic data........................................................................................................................................................26 Design traffic calculations.................................................................................................................................27 Aggregate details..............................................................................................................................................27 Calculations ......................................................................................................................................................28

Example 2 Double/Double reseal ...............................................................................29 Job details.........................................................................................................................................................29 Aggregate .........................................................................................................................................................29 Traffic Data .......................................................................................................................................................29 Design Calculations..........................................................................................................................................30

Example 3 Single/Single 7 MM seal ...........................................................................31 Job details.........................................................................................................................................................31 Aggregate .........................................................................................................................................................31 Traffic Data .......................................................................................................................................................31 Design Calculations..........................................................................................................................................32

INFORMATION RETRIEVAL ............................................................................................33


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PART I SIZE 10 MM and LARGER AGGREGATES

1. INTRODUCTION

1.1 Assumptions

The Austroads sprayed seal design method for size 10 mm or larger aggregate is based on the following assumptions:

the average least dimension of the aggregate is determined by direct measurement

correct prime/primerseal design and application. Where this has not been achieved, remedial work should be undertaken prior to, and well in advance of, the commencement of sealing

the aggregate is sound and single-sized

aggregate is spread in a uniform layer of one stone thickness, with particles in continuous, partly interlocked contact, with the least dimension near vertical

the aggregate spread rate determines the inter-aggregate void space in the seal layer, and hence the amount of binder required

the aggregate spread rate does not contain an allowance for whip-off. Failure to achieve the correct aggregate spread rate will result in the designed binder application rate being incorrect.

By contrast, the design method for seals with aggregate size 7 mm or less (see Part II) differs from the method for larger aggregate seals in that:

the sealing aggregate is not generally tested to determine the average least dimension

7 mm seals or smaller are commonly used as correction courses to provide an interim even surfacing prior to the placement of a more durable surface treatment

7 mm seals or smaller are used in situations that can tolerate a reduced surfacing life, such as where a temporary surfacing is required.


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1.2 Design Philosophy (Basis for method)

The design philosophy is based on the following:

use of single-sized aggregate as described in NAASRA (1989), Chapter 4

single layer of aggregate particles has typically 40 to 60 % voids

binder should be 50 to 60% up the height of the aggregate particle (i.e., to two years after construction)

aggregate particles may penetrate (embed) into the base

reseals interlock with the substrate

surface texture (macro and micro) is required for skid resistance

binder may be absorbed into the base and aggregate

binder filled voids may be varied to optimise surface texture requirements and seal life.


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2. AGGREGATE SPREAD RATE

2.1 Conventional binder

For 10 mm and larger seals and reseals using conventional binder, the amount of aggregate required is based on its Average Least Dimension (ALD) and should be calculated using the following equation:

The aggregate spread rate (m2/m3) = ALD900 ...............[Equation 1]

Where:

ALD = Average Least Dimension (mm)

Calculated spread rates of aggregate for single/single seals and reseals, based on 900/ALD, are shown in Figure 1.

50

100

150

200

250

4 5 6 7 8 9 10 11 12

Average Least Dimension (mm) Fig. 1 Aggregate spread rate for seals and reseals

Note: The above spread rates do not include allowances for spreading or stockpile wastage. A typical allowance for stockpile wastage is 5 to 10 %.

2.2 Very Low Traffic Roads

To achieve a satisfactory mosaic and/or to prevent pick-up of the binder immediately following application, the application of aggregate should be 5% heavier on very low trafficked roads (less than 200 v/l/d).


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2.3 Polymer Modified Binders (PMBs)

For 10 mm and 14 mm sealing and resealing applications using polymer modified binders, e.g., High Stress Seal (HSS), Strain Alleviating Membrane (SAM), Strain Alleviating Membrane Interlayer (SAMI), etc., the required aggregate spread rate is based on its Average Least Dimension (ALD) and should be calculated in accordance with the appropriate equation in Table 1.

TABLE 1 10 & 14 mm Aggregate Spread Rate for PMBS

Traffic Condition Equation 2

Light traffic The aggregate spread rate (m2/m3) = ALD750

Medium to heavy traffic The aggregate spread rate (m2/m3) = ALD

800

Where: ALD = Average Least Dimension (mm)

2.4 Bitumen Emulsion Binders

For all 10 mm and 14 mm seals and reseals using emulsion binders (including emulsified conventional bitumen and PMBs), the required aggregate spread rate is based on its Average Least Dimension (ALD) and should be calculated in accordance with the appropriate equation in Table 2.

TABLE 2 10 & 14 mm Aggregate Spread Rate for Emulsions

Aggregate layer configuration Equation 3

Single The aggregate spread rate (m2/m3) = ALD750

Single

with 7 mm (or smaller) Scatter Coat (rack-in)

The aggregate spread rate (m2/m3) = ALD800

The aggregate spread rate (m2/m3) = 400 600

Where: ALD = Average Least Dimension (mm)


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3. BINDER APPLICATION RATE FOR SINGLE/SINGLE SEALS

3.1 General

The design objective is for the residual binder to be about 50 to 60% of the height of the aggregate layer two years after construction. The residual binder comprises bitumen, flux oil and adhesion agent, but does not include cutter oil or water. The amount of binder required will depend on the size, shape and orientation of the aggregate particles, embedment of aggregate into the base, texture of surface onto which the seal is being applied, and absorption of binder into either the pavement or aggregate.

All application rates determined by this method are stated in L/m2, of residual binder at a temperature of 15C. In determining the actual field application rate, allowances must be made for a proportion of the cutter oil or water (emulsions) and the volume corrected for the spraying temperature.

3.2 Factors Affecting the Binder Application Rates

Orientation and embedment are mainly functions of rolling, traffic compaction and substrate properties. It is essential that adequate, timely rolling is carried out, particularly at very low traffic volumes, < 100 vehicles/lane/day (v/l/d), to achieve initial aggregate interlock, orientation and embedment.

The binder quantity required is also influenced by the shape of the aggregate and the volume and nature of the traffic, in particular, heavy vehicles. Adjustments are made to the Basic Voids Factor, Vf , depending on the aggregate properties and traffic conditions.

The basic design is based on average shape of the aggregates, i.e., with a flakiness of about 20 to 25%. Cubical or rounded aggregate particle shapes require a higher quantity of binder to aid retention, than elongated flakey particles.

If increasing traffic volumes are predicted, particularly an increase in heavy vehicles, a reduction in the required binder quantity may be necessary due to further reorientation and aggregate embedment. A further reduction in the required binder quantity may be necessary due to situations where the traffic is channelised.

Allowances are made to the basic binder application rate for existing surface texture conditions, aggregate and pavement absorption, and for hardness of the existing surface (ball embedment measurement) in the case of seals.

A flow chart for determination of aggregate spread rates and binder application rates for single/single sprayed seals is shown in Figure 2.


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Seal Intentions * Road environment * Asset management criteria * Treatment type

Traffic Volume (vehicles/lane/day)

Basic Voids Factor, Vf (L/m2/mm)

Fig. 3

Traffic Effects, Vt * Composition * Untrafficked areas * Short term effects * Climbing lanes * Passing lanes * Curvature * Intersections * Narrow lanes Table 4

Voids Factor

Adjustments

Aggregate, Va shape and size

Table 3

Design Voids Factor, VF

Basic Binder Application Rate, BB

(L/m2) = VF x ALD

Aggregate ALD

Surface Texture, AST of existing seal

Table 6 Binder Absorption, ABA

* by aggregate * by pavement Table 5

Embedment, AE (seals only)

Fig. 4

Allowances (L/m2)

Design Binder Application Rate, BD

(L/m2) Traffic Volume (vehicles/lane/day)

Design Aggregate

Application Rate

Fig. 1

(L/m2/mm)

Fig. 2 Determination of aggregate spread and binder application rates for single/single sprayed seals.


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4. BASIC VOIDS FACTOR (Vf) The Basic Voids Factor, Vf (L/m2/mm), is related to traffic level and is determined from Figure 3a or 3b (depending on traffic volume), and should be read to the nearest 0.005. The designer should use the central target line as the Basic Voids Factor in all cases.

Figures 3a and 3b also contain the upper and lower lines which represent indicative limits for the Design Voids Factor, VF (see 5.1). Practitioners must exercise caution if adopting Design Voids Factors outside these limits.

0.15

0.20

0.25

0.30

0 100 200 300 400 500


Bleeding Limit Target Stripping Limit

Fig. 3a Basic Voids Factor (Vf) Traffic Volume 0 500 vehicles/lane/day

0.05

0.10

0.15

0.20

500 1500 2500 3500 4500 5500 6500 7500 8500 9500


()

Bleeding Limit Target Stripping Limit

Fig. 3b Basic Voids Factor (Vf) -Traffic Volume 500 10,000 vehicles/lane/day

The Bleeding/Flushing Limit indicates the factor beyond which the resultant texture depth may be too low, leading to bleeding in the seal. The Stripping Limit indicates the factor beyond which the resultant texture depth may be too high, leading to stripping of the seal.


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5. ADJUSTMENTS

5.1 General

The Design Voids Factor, VF (L/m2/mm), is determined by adjusting the basic voids factor (Vf) to account for aggregate characteristics (Va) and for traffic effects (Vt). These factors are cumulative.

Design Voids Factor, VF = Vf + Va + Vt .........................[Equation 4]

5.2 Aggregate Adjustment (Va)

An adjustment, Va, is made to the Basic Voids Factor to account for the variation in aggregate characteristics in accordance with Table 3.

TABLE 3 Aggregate Shape Adjustment (Va) to Basic Voids Factor

Aggregate Type Aggregate Shape Flakiness Index (%) Adjustment to Vf (L/m2/mm)

Crushed Flaky

Angular

Cubic

26 to 35

15 to 25

< 15

- 0.010 to + 0

+0 to +0.005

+ 0.010

Partly crushed Not applicable + 0.005

Rounded Not applicable + 0.01

5.3 Adjustment for Traffic Effects (Vt)

The Basic Voids Factors, Vf, described in Section 4, have been developed for an average mix of light and heavy vehicles in free traffic flow. An adjustment, Vt, needs to be made for variations in traffic composition, in particular for heavy vehicles, vehicle speeds, climbing lanes and abnormal concentration of vehicle effects refer Table 4.

Where traffic is channelled into confined wheel paths such as on single lane bridges, tight radius curves or confined lane widths, an appropriate adjustment to the Basic Voids Factor (Vf) must be made to reduce the risk of the seal bleeding. For example, a confined single lane bridge may increase the effective traffic loading in the wheel path as much as three-fold when the cumulative effects of combining lane volumes and constraining traffic to a confined path are taken into account.

Possible short increases in traffic volumes such as during grain harvest, local field days, etc., may occur early in the life of the seal. Designers should take this into account and may need to make some adjustment to the design traffic volumes adopted in the design procedure.


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TABLE 4 Traffic Effects Adjustment (Vt) to Basic Voids Factor

ADJUSTMENT TO BASIC VOIDS FACTOR (L/m2/mm)

Flat or downhill Slow moving climbing lanes

TRAFFIC EFFECT

Normal Channelised* Normal Channelised*

15 - 30 % H.V. -0.01 -0.02 -0.02 -0.03

> 30% H.V. -0.02 -0.03 -0.03 -0.04

Fast moving cars only (overtaking lanes of multi-lane

rural roads) +0.01 0 N/A N/A

Untrafficked areas (shoulders, medians) +0.02 N/A N/A N/A

N/A Not applicable

H.V. Heavy Vehicles

* Channelisation - a system of controlling traffic by the introduction of an island or islands, or markings on a carriageway to direct traffic into predetermined paths, usually at an intersection or junction. This also applies to approaches to bridges and narrow culverts.

The Design Voids Factor may now be calculated in accordance with Equation 4.


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6. BASIC BINDER APPLICATION RATE (BB) The procedure for the determination of the basic binder application rate, BB (L/m2) for the proposed seal and reseal treatments is as follows (see also Figure 2):

1. Determine the Basic Voids Factor, Vf, to the nearest 0.005 from Fig. 3a or 3b.

2. Apply aggregate and traffic voids factor adjustments, Va (Table 3) and Vt (Table 4) to determine Design Voids Factor, VF.

3. The ALD is determined in accordance with Austroads Test Method SDT 01.

4. The basic binder application rate, BB is determined to the nearest 0.01 L/m2 by

multiplying the Design Voids Factor (VF) by the ALD, as shown in the following equation:

BB = VF x ALD .................................................[Equation 5]


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7. ALLOWANCES The following allowances are determined to the nearest 0.1 L/m2 and are cumulative. They must be added to, or subtracted from, the Basic Binder Application Rate to determine the Design Binder Application Rate, BD (L/m2).

Allowances in L/m2 are made for the following:

surface texture of existing surfacing, the surface texture determined by the sand patch method in accordance with Austroads Test Method SDT 02, for reseals and seals over primerseals (Table 6)

binder absorption by the aggregate and/or the existing pavement (Table 5),

aggregate embedment into existing surface (for sealing treatments only) Figure 4.

Some aggregate sizes will not be readily compatible with existing seal sizes and texture depths, e.g., small-sized reseals will generally not give good results over flushed large-sized seals and 10 mm reseals sometimes do not interlock well with hungry 14 mm and 10 mm seals. Allowances for existing surface texture may be substantial, and require a degree of judgement by the designer.

7.1 Texture Allowance (AS)

7.1.1 Retreatment of Existing Seals

The allowances to be made for different sizes of resealing aggregate over various existing seal sizes and textures assumes satisfactory interlock between aggregates. There may be some aggregates that have unusual (atypical) shape or size, which require minor variations from the tabulated values (see Table 6).

7.1.2 Resealing over Asphalt

For an asphalt surface the sand patch test would not usually be appropriate. In this case, an allowance based on a visual assessment may be necessary. Based on experience, the allowance should be +0.0 to +0.3 L/m2. Where the asphalt is slick with fatty patches, the ball penetration test may be appropriate. For further details, refer to Austroads (2000), Part I .

7.1.3 Resealing over Slurry Surfacing

For a slurry surfacing the sand patch test would not usually be appropriate. In this case, an allowance based on visual assessment may be necessary. For further details, refer to Austroads (2000), Part I .


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7.1.4 Resealing over Primed Concrete Surfaces

For a well-primed concrete surface, the sand patch test may not be appropriate. In this case, an allowance based on a visual assessment may be necessary. Based on experience, the allowance should be +0.2 to +0.4 L/m2.

7.1.5 Resealing over Timber Surfaces

For a timber surface, the sand patch test is not appropriate. Timber may be untreated, primed, coated or impregnated. An allowance based on experience and visual assessment may be necessary. As a guide an allowance between +0.2 to +0.4 L/m2 may be appropriate.

7.1.6 Sealing Treatments

Sealing treatments on primersealed surfaces will be treated as for reseals in 7.1.1 above for surface texture effects except that the ball penetration test should be carried out to determine if an additional embedment allowance needs to be included.

For a seal over a primed surface, the sand patch test is not appropriate. In this case, a texture allowance based on a visual assessment may be necessary. Based on experience, the allowance should be +0.0 to +0.2 L/m2. In addition, a ball penetration test value and embedment allowance may also need to be included.

7.2 Binder Absorption Allowance (ABA)

It will be necessary to increase the binder application rate to allow for any binder absorption by aggregate and pavement, ABA, but it is not possible to give a general allowance.

7.2.1 Binder Absorption by Aggregate

Absorptive aggregates may fall into two general categories, ie., those which are:

porous, eg. sandstone, rhyolite, etc.

vesicular (full of cavities), eg. scoria, slags, etc.

An aggregate should be tested for binder absorption in accordance with AUSTROADS Test Method SDT 03. Generally, the allowance for binder absorption by aggregate does not exceed +0.1 L/m2. Precoating alone will not usually compensate for absorption. The appropriate allowance to be added should be made in accordance with Table 5. However, in extreme cases, allowances of up to + 0.3 L/m2 may be needed with some of these types of aggregates.


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TABLE 5 Allowances for Binder Absorption by Aggregate , ABA (Austroads Test Method SDT 03)

Binder Absorption, (%) Absorption Allowance, (L/m2)

1 +0 to +0.1

> 1 to 3 + 0.1 to +0.3

> 3 Do not use unless performance is proven

7.2.2 Binder Absorption by Pavement

Seals

For seals, the binder may drain into voids in the base course if these have not been adequately filled by a prime or primerseal. This is most likely to occur in sandy or silty rubble base courses (sandstone, limestone or silty gravels) in a hot dry climate. For unusually absorptive pavement surfaces, particularly in hot climates, long-term absorption of the binder into the base course can occur. The allowance for this will generally be between + 0.1 to + 0.2 L/m2. Where more than 0.2 L/m2 is required, an alternative treatment should be used.

Alternative treatments may comprise:

use of different grade or class of binder including PMBs

modification or stabilisation of the base

use of a small nominal size seal

in extreme cases, this may lead to an early enrichment, being required.

Reseals

Binder absorption into the substrate will seldom be a problem in reseals, unless the existing surface is visibly porous.


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TABLE 6 Surface Texture Allowance For Existing seals, AS (L/m2)

Existing Seal Proposed Reseal Size Condition Texture Depth 5 mm 7 mm 10 mm 14 mm 5 mm Bleeding a b -0.2 -0.2 -0.2

Flushed < 0.7 mm b -0.1 - - Smooth 0.9 mm - - - - Matt 1.0 mm - +0.1 +0.1 +0.1 Hungry 1.4 mm +0.2 +0.2 +0.2 +0.2 Very Hungry > 1.8 mm +0.3 +0.3 +0.3 +0.3

7 mm Bleeding a b -0.2 -0.2 -0.2 Flushed < 0.7 mm -0.1 -0.1 -0.1 - Smooth 1.0 mm - - - - Matt 1.2 mm - +0.1 +0.2 +0.2 Hungry 1.7 mm +0.2 +0.2 +0.3 +0.3 Very Hungry > 2.0 mm +0.3 +0.4 +0.4 e +0.4

10 mm Bleeding a b -0.2 -0.2 -0.2 Flushed < 0.7 mm -0.1 -0.1 -0.1 - Smooth 1.0 mm - - +0.1 +0.2 Matt 1.4 mm +0.1 +0.2 +0.3 +0.4 e Hungry 1.9 mm +0.2 +0.3 +0.4 e +0.5 e Very Hungry > 2.2 mm +0.3 +0.4 +0.5d +0.6 d

14 mm Bleeding a c b -0.3 -0.3 Flushed < 0.7 mm b -0.1 -0.1 -0.1 Smooth 1.0 mm - - + 0.1 +0.2 Matt 1.6 mm +0.1 +0.2 +0.4 e +0.4 e Hungry 2.4 mm +0.2 +0.3 +0.5 e +0.6 d Very Hungry > 3.2 mm +0.3 +0.4 +0.6 d +0.7 d

20 mm Bleeding a c b -0.3 -0.3 Flushed < 0.7 mm c -0.1 -0.1 -0.1 Smooth 1.0 mm - - +0.1 +0.2 Matt 1.8 mm +0.1 +0.2 +0.4e +0.4 e Hungry 2.9 mm +0.2 +0.3 +0.5 e +0.6 d

Very Hungry > 3.5 mm +0.3 +0.4 +0.6 d

+0.8 d

a Embedment considerations dominant

b Not recommended

c Specialised treatments necessary

d Consider alternative treatments (fog coat, small size seal or others)

e This treatment might not be advisable depending on the shape and interlock of aggregates

- Where no value is shown, a value may be interpolated to the nearest 0.1 L/m2.


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7.3 Embedment Allowance (AE)

Embedment allowance compensates for loss of voids in the seal under traffic due to the sealing aggregate being punched into the surface of the substrate. This will depend on the volume and mass of traffic, and the condition (hardness) of the substrate (Fig. 4).

7.3.1 Seals

Embedment of aggregate may occur:

in an initial treatment applied over a soft base

in a sealing treatment applied over a primed or primersealed surface.

Typical embedment allowances (in L/m2) for sprayed seals are shown in Figure 4. Existing pavement surface hardness should be determined by the Ball Penetration Test, in accordance with the Austroads Test Method SDT 04.

- 0.1 L/m2

NIL

- 0.2 L/m2

- 0.3 L/m2

- 0.4 L/m2

NIL 1000 2000 3000 4000 5000


1

2

3

4

5

6

7

8

Fig. 4 Embedment allowance for seals

Note: Where embedment allowances of -0.3 L/m2 or more are indicated, consideration should be given to alternative treatments such as armour-coating with higher quality materials rolled into the surface of the base or the use of a primerseal/prime and seal with a small aggregate in order to provide a platform on which a larger aggregate seal may then be placed.


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A U S T R O A D S 2 0 0 2

7.3.2 Reseals

Embedment of aggregate may occur in reseals:

if there is free binder on the surface being resealed

when applying a reseal over fresh asphalt or slurry surfacings.

Where the binder in the existing seal is relatively soft, some embedment may occur. For further details, refer to Austroads (2000), Part I.


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8. DESIGN BINDER APPLICATION RATE (BD)

8.1 Conventional Binders

Where conventional binders are used, the Design Binder Application Rate, BD, may be determined by the following equation:

BD = BB + Allowances..........................................[Equation 6a]

Where:

BB = Basic Binder Rate determined in accordance with Equation 5, rounded to the nearest 0.1 L/m2

Allowances = as determined in Tables 5 and 6, Fig. 4 and Section 7

8.2 Emulsion Binders

Where emulsion binders are used, the Design Binder Application Rate, BD, may be determined by the following equation:

BD* = (BB x EF) + Allowances ..................................[Equation 6b]

Where:


EF = Emulsion Factor (from Table 7)


Note: * litres of residual bitumen per square metre

For emulsions using polymer modified bitumen binders, the Design Binder Application Rate, BD, may be determined by the following equation:

BD* = (BB x PF x EF) + Allowances .............................. [Equation 6c]

Where:


EF = Emulsion Factor (from Table 7)

PF = Polymer Factor (from Table 8)


Note: * litres of residual bitumen per square metre

TABLE 7 Emulsion Factor

Product Emulsion Factor (EF)

Conventional emulsion (60%) 1.0

High Bitumen Content Emulsion (67 %) 1.1 1.2


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8.3 Polymer Modified Binders (PMBs)

Where Polymer Modified Binders are used the Design Binder Application Rate, BD, may be determined by the following equation:

BD = (BB x PF) + Allowances ...................................[Equation 6d]

Where:


PF = PMB Factor (from Table 8)


TABLE 8 SAM PMB Factor (PF)

Product* S10E (as an HSS)

S10E (holding treame

nt)

S15E S20E S35E S45R S50R S55R EVA **

Factor (PF) 1.10 1.15 1.20 1.30 1.30 1.45 1.45 1.70 1.25

Note: The above factors apply for all traffic levels. Intended for both SAM and HSS applications. A higher factor may be required for a SAMI application and/or where the use of an S25E or S30E is considered.

* Where other polymer modified binders are used, an appropriate factor should be determined for the particular material.

** Sometimes used in emulsion applications

These factors are designed to provide the maximum practicable binder application rate to optimise resistance to reflective cracking and to waterproof the pavement. For HSS applications, where surface texture is the primary objective, the PMB factors (PF) in Table 8 may be reduced but should not be less than 1.10.

CAUTION - The above factors are solely applicable to this design method.


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PART II SIZE 7 MM and SMALLER AGGREGATES

9. DESIGN APPLICATION RATES FOR SIZE 7 MM and SMALLER AGGREGATES

9.1 General

The design philosophy for size 7 mm and smaller aggregates is similar to size 10 mm and larger aggregates except that:

the sealing aggregate is not generally tested to determine the average least dimension

7 mm seals or smaller are commonly used as correction courses to provide an interim even surfacing prior to the placement of a more durable surface treatment

7 mm seals or smaller are used in situations that can tolerate a reduced surfacing life, such as where a temporary surfacing is required.

Adjustments and allowances to the Basic Voids Factor and Basic Binder Application Rate need to be considered. A flow diagram (see Figure 5) illustrates the design method for the 7 mm and smaller seals.

9.2 Aggregate Spread Rate

In general, a typical aggregate spread rate for size 7 mm and smaller aggregates is about 200250 m2/m3, however the broad ranges of typical spread rates for 7 mm and smaller aggregates take into account different seal objectives. Lower aggregate applications are used in conjunction with light binder application rates where designed to fill the spaces in a coarse textured surface, e.g. correction seals. Heavier aggregate applications are applied where a completely interlocked aggregate layer is required. This may result in more than one thickness of aggregate particles. The following table may be used as a guide to the selection of appropriate spread rates.


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TABLE 9 7 mm aggregate spread rates

Seal Type Number of aggregate thicknesses

Rate (m2/m3)

Seal/Reseal 1 260 290

> 1 200 250

Scatter (rack-in) Coat 1 400 600

2nd Coat of Double/Double - 300 340

9.3 Binder Application Rates

In some areas, it is not usual to determine ALD for aggregates sized 7 mm or smaller. For small and flaky aggregates where the ALD is less than half the nominal size, the resultant seal will be more than one aggregate particle thickness. Basic spread rates in Table 10 may be used for 7 mm and smaller aggregates. Normal design allowances are applied to determine the design binder application rate.

9.3.1 Information Required

aggregate grading, if no ALD information available

design traffic, including % heavy vehicles

allowances for surface texture, absorption, etc. For further details, refer to Austroads (2000), Part II.

9.3.2 Basic Binder Application Rate (BB)

If ALD is not available then determine a basic binder application rate, BB (L/m2), from Table 10, taking into account the notes at the bottom of the table.

If ALD is available then a basic voids factor can be determined from Figure 3. Adjustments for aggregate (Table 3) and traffic (Table 4) are added to the basic voids factor to derive the design voids factor which is multiplied by the ALD to derive a basic binder application rate. For further details, refer to Austroads (2000), Part II .

9.3.3 Design Binder Application Rate (BD)

Determine the design binder application rate by adding allowances for surface texture, AS (Table 6), binder absorption, ABA (Table 5) and embedment, AE (Figure 4) to the selected basic binder application rate. For further details, refer to Austroads (2000), Part II Section 4.


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Table 10 Basic Binder Application Rates for Size 7 mm and Smaller Aggregates

Vehicles/lane/day, (v/l/d) Basic Binder Application Rate, BB (L/m2)

< 100 0.8 - 1.0

100 600 0.7 - 0.9

601 1200 0.6 - 0.8

1201 2500 0.5 - 0.7

> 2500 0.5

Notes:

a. The lower of the basic binder application rates should be selected for use with flaky aggregates. The higher of the basic binder application rates should be selected for use with more cubically shaped aggregates.

b. The lower of the basic binder application rates should be used where traffic includes 10% HV or higher.

c. If not certain of the conditions and traffic composition, it is recommended the mid-point basic binder application rate be selected.

d. If the smaller aggregate is part of the second application of a double/double seal applied within a short time after the first application, then it is recommended that the lower of the basic binder application rates be selected and no allowances added.


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Basic Application

Binder Rate BB

Table 10

ALD

Basic Voids Factor Vf

(L/m2/mm) Fig. 3

NO ALD


Allowances (L/m2)

* Surface texture (Table 6) * Binder absorption (Table 5) * Embedment (Fig. 4)

Basic Binder Applcation Rate BB (L/m2)

BB= ALD x VF


Design Voids VF (L/m2/mm) VF = Vf + Vt + Va

Fig. 3, Table 4 & Table 3

Design Binder Application Rate, BD (L/m2)

BD = BB + Allowances

Fig. 5 Determination of binder application rate for 7 mm and smaller single/single sprayed seals


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PART III DOUBLE/DOUBLE SEALS

10. DESIGN APPLICATION RATES FOR DOUBLE/DOUBLE SEALS

10.1 General

A double/double seal consists of two applications of binder each followed by an application of aggregate. Double/double seals may be laid in two ways:

both applications placed on the same day.

the second application delayed

10.2 Both Applications on the Same Day

Where the second application is to be applied immediately after the first, with little or no trafficking between applications, the following design procedure may be used.

design the first application using the procedure for a single/single sprayed seal, except modify the Design Voids Factor (VF) by the amount as shown in Table 11 provided the that the Design Binder Rate (BD) remains above 0.1 ALD. Interpolation between values is permitted.

apply adjustments as normal as for a single/single seal

the aggregate application for the first layer of aggregate should be reduced by 10%

design the second application as for a single/single reseal but without the addition of any allowances for surface texture or embedment. Binder Absorption Allowance, ABA , is to be added.

aggregate in the second application is normally no more than half the size of the first, and spread rate is just sufficient to fill the voids in the first application.


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TABLE 11 Modification To Design Voids Factor for the First Seal of a Double/Double Seal

Traffic Volume (vehicle/lane/day)

Modification to VF (%)

< 500 25 500 1000 20 1001 2000 15

> 2000 10

To retain more of the second layer of aggregate in the final mosaic, calculate the total binder application rate for both layers and, if the traffic volume allows, proportion the binder application rate for each layer more evenly. For example, apply 55% of the total binder in the first layer, and 45% in the second. In some circumstances, the lower application rate may be placed on the bottom to ensure there is sufficient binder to hold the second aggregate in place.

It should be noted that the first application is very vulnerable to traffic damage, and the second application must be applied on the same day.

10.3 For the Second Application Delayed

Where the second application is to be applied after 1 week and up to several months after the first, and the seal will be trafficked during this delay:

the first application should be designed as a single/single seal, and

the second application should be designed as a single/single seal (or alternatively, BD may be reduced to the minimum basic rate given in Table 10) and the aggregate application reduced by up to 30%. This should fill the void spaces in the first application and avoid excessive aggregate loss.


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REFERENCES

APRG (1999) Pavement Technology Glossary of Terms, APRG 99/12 (MA)

AUSTROADS (1990) AUSTROADS Design of Sprayed Seals, July 1990, 6 pgs

AUSTROADS (1999a) Calibration of bitumen sprayers - Part 0: General introduction and list of Methods, Austroads Test Method SDT 01.0

AUSTROADS (1999b) Calibration of bitumen sprayers - Part 1: Volumetric Calibration, Austroads Test Method SDT 01.1

AUSTROADS (1999c) Calibration of bitumen sprayers - Part 2: Transverse Distribution by fixed pit facility, Austroads Test Method SDT 01.2

AUSTROADS (1999d) Calibration of bitumen sprayers - Part 3: Transverse Distribution by RTA field method, Austroads Test Method SDT 01.3

AUSTROADS (1999e) Calibration of bitumen sprayers - Part 4: Transverse Distribution by BCA field method, Austroads Test Method SDT 01.4

AUSTROADS (1999f) Calibration of bitumen sprayers - Part 5: Road Speed calibration, Austroads Test Method SDT 01.5

AUSTROADS (1999g) Calibration of bitumen sprayers - Part 6: Viscosity of test fluid Determination, Austroads Test Method SDT 01.6

AUSTROADS (2000) AUSTROADS Provisional Sprayed Seal Design Method Revision 2000, Technical Note AP-T09

AUSTROADS Guide to the Selection of Road Surfacing, Austroads Publication No. AP-63/00.

AUSTROADS (2001a) Average least dimension of aggregate by direct measurement (nominal size 10 mm and greater), Austroads Test Method SDT 01

AUSTROADS (2001b) Modified Surface Texture Depth (Pestle Method), Test Method SDT 02

AUSTROADS (2001c) Absorption of Bituminous Binder into Aggregate, Austroads Test Method SDT 03

AUSTROADS (2001d) Ball Penetration Test, Austroads Test Method SDT 04

AUSTROADS (2001e) Absorption of Primer or Binder by Road Gravel, Austroads Test Method SDT 05a

AUSTROADS (2001f) Penetration of road bases by bituminous primers or primerbinders, Austroads Test Method SDT 05b

AUSTROADS (2001g) Seal Behaviour, Test Method SDT 06

NAASRA (1989) Bituminous Surfacing - Sprayed Work, Technical Report, NTR-07, National Association of Australian State Road Authorities.


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APPENDIX 1 SEAL DESIGN EXAMPLES

GENERAL Following are three design examples provided to show typical designs that may be required to be carried out using this method. These cover a range of traffic volumes and highlight the various adjustments and allowances that may be required to be taken into consideration, as well as the calculations that must be carried out to determine the binder application rate and aggregate spread rate.

For convenience a pro-forma has been designed and used for these design examples. It generally follows the procedure recommended in Fig. 2 Determination of aggregate spread rates and binder application rates for single/single sprayed seals and will assist with ensuring that all relevant adjustments and allowances are taken into consideration.

EXAMPLE 1 SINGLE/SINGLE RESEAL A 14 mm reseal on a highway with a high traffic volume.

One carriageway of a duplicated highway is to be resealed to provide waterproofing and skid resistance for at least 5 years, at which time it is expected this section will be rehabilitated and upgraded by the addition of another lane and reconstructing the existing lanes. The area to be resealed is an uphill section of the highway.

Job details

Sealed pavement consists of 2 traffic lanes of 3.7 m width plus a sealed 2.7 m shoulder on the left-hand side.

a) The left-hand lane was rutted and also had some distressed areas. This has been patched and regulated with asphalt. The surface texture is uniform in appearance. It is too smooth for the sand patch test to determine a surface texture, and an allowance will need to be estimated based on experience. The asphalt is just over 12 months old. An allowance of +0.1 L/m2 is considered appropriate.

b) The right-hand lane is a seal of size 10 mm basalt aggregate. It is reasonably uniform in appearance and texture, although along the edges and between the wheel paths the texture is slightly coarser, but not enough to warrant a correction treatment. Sand patch test results give an average surface texture of 1.5 mm.

c) The shoulder is a seal of size 7 mm basalt applied at some stage to prevent further loss of the original size 10 mm aggregate. It is uniform in appearance but has a very coarse texture. The sand patch test results give an average surface texture of about 2.4 mm.

Traffic data

Traffic 15 000 AADT, including 15% heavy vehicles.


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Design traffic calculations

Assume traffic is equal over the two carriageways, thus each carriageway carries 15000/2 = 7500 vehicles per day.

Assume kerb lane takes 60% and median lane takes 40% of traffic

Kerb lane = 60/100 7500 = 4500 v/l/d

Median lane = 40/100 7500 = 3000 v/l/d

Heavy vehicles are all assumed to have travelled in the LH lane. Heavy vehicles were given as 15% of the total AADT and it is necessary to calculate the actual % of heavy vehicles in the LH lane in order to be able to make an appropriate adjustment to the basic voids factor. Heavy vehicles = 15/100 7500 = 1125 for this carriageway. This equals 1125/4500 = 25% of the traffic on the LH lane.

Aggregate details

Size/type: 14 mm, basalt Flakiness index: 20% ALD: 8.6 mm Binder Abs. by Agg.: 0.0% Binder Abs. by Pvt.: 0.0%


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Calculations

Job location Symbol Units Kerb lane Median lane Shoulders Traffic - AADT 15000 15000 Adopt < 50 Design Traffic - v/l/d 4500 3000 See Table 2 Basic Void Factor Vf - 0.13 (Fig 3b) 0.14 0.23 (Fig 3a) Adjustments:

Aggregate Shape Traffic Effects

Other

Va Vt -

L/m/mm L/m/mm L/m/mm

nil

0.02 (Table 4) nil

nil

0.01 nil

nil

+ 0.02 (Table 4) nil

Design Void Factor Vf + Va + Vt

VF - 0.11 0.15 0.25

ALD of aggregate ALD mm 8.6 8.6 8.6 Basic Binder Rate VF x ALD

BB L/m 0.11 8.6 = 0.95 0.15 8.6 = 1.29 0.25 8.6 = 2.15

Allowances: Surface texture

Binder Abs. by Agg, Pvt Embedment

AST ABA AE

L/m L/m L/m

+ 0.1 nil, nil

nil

+ 0.4 nil, nil

nil

+ 0.4 nil, nil

Design Binder Rate BB + AS + ABA + AE

BD L/m 0.95 + 0.1 = 1.05 adopt 1.0

(due to high traffic)

1.29 + 0.4 = 1.69 adopt 1.7

2.15 + 0.4 = 2.55 adopt 2.5

(see NOTE)

Aggregate rate of application

- m2/m3 900/8.6 = 104.6 adopt 105

adopt 105

adopt 105

NOTE: 2.55 L/m2 for the shoulder is considered to be an expensive option and with a high risk of binder drainage in hot weather. The design application rate adopted could be reduced from 2.55 to 2.5 L/m2 without risk of stripping. However, the preferred alternative is to consider selecting a 10 mm or 7 mm aggregate, as these would be cheaper whilst also providing the necessary waterproofing. These would also have good texture, although this is not considered to be an issue on the non-traffic shoulder.


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EXAMPLE 2 DOUBLE/DOUBLE RESEAL A double/double reseal on a medium traffic volume access road.

An access road to an industrial subdivision has been primersealed to cater for the construction traffic, and is to have the final double/double reseal applied prior to opening to all traffic. Both applications are be completed before opening to traffic.

Job details

a) Alignment is straight and level. An intersection near the end of the work, providing access into the subdivision, will be surfaced with a dense graded asphalt. Pavement is 7.6 m between kerbs.

b) Existing primerseal is a size 7 mm, with a uniform surface texture average about 1 mm as measured with the sand patch test. The primerseal is over 12 months old and has a very tight mosaic. Aggregate embedment of the final seal is considered to be nil.

Aggregate

Size/type: 14 mm & 7 mm basalt Flakiness index: 15% - ALD: 8.7 mm Not measured Binder Abs. by Agg.: 0.0% 0.0% Binder Abs. by Pvt.: 0.0%

Traffic Data

Traffic is estimated to be about 1800 AADT, with over 30% heavy vehicles.


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Design Calculations

Job location Symbol Units 1st Application (14 mm) 2nd Application (7 mm) Traffic - AADT 1800 Design Traffic - v/l/d 900 900 Basic Void Factor Vf - 0.16, reduce by 20% = 0.13 See Table 9 Adjustments:


Other

Va Vt -

L/m2/mm L/m2/mm L/m2/mm

+ 0.005 - 0.02

nil


VF - 0.115 n/a

ALD of aggregate ALD mm 8.7 n/a Basic Binder Rate VF x ALD

BB L/m 0.115 8.7 = 1.00 Table 10 0.6 0.8, 600 to 1200 v/l/d;

for 900 v/l/d adopt 0.7 Allowances:

Surface texture Binder Abs. by Agg, Pvt

Embedment

AST ABA AE

L/m L/m L/m

+ 0.2 nil, nil

nil

n/a

n/a, n/a n/a


BD L/m 1.00 + 0.2 = 1.20 adopt 1.2

adopt 0.7


- m2/m3 900/8.7 * 1.1 = 113.8 adopt 114

Range 300 340 adopt 340


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EXAMPLE 3 SINGLE/SINGLE 7 MM SEAL A Single/Single 7 mm seal on low traffic with no heavies.

A low traffic council road has been recently reconstructed and primed. It is to have a single/single seal applied.

Job details

a) Alignment is straight and level.

b) Existing primed surface has a ball penetration value of 4 mm. The surface is uniform but slightly roughened. The colour of the surface is dark brown to black and is considered waterproof.

Aggregate

Size/type: 7 mm crushed river gravel Flakiness index: 5% Shape: Cubical ALD: 3.6 mm Binder Abs. by Agg.: 1.0% Binder Abs. by Pvt.: Nil

Traffic Data

Traffic is estimated to be about 100 AADT, with less than 5% heavy vehicles.


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Design Calculations

Job location Symbol Units 1st Application (10 mm) Traffic - AADT 100 Design Traffic - v/l/d 50 Basic Void Factor Vf - 0.23 Adjustments:


Other

Va Vt -

L/m2/mm L/m2/mm L/m2/mm

+ 0.01

nil nil


VF - 0.23

ALD of aggregate ALD mm 3.6 Basic Binder Rate VF x ALD

BB L/m 0.23 3.6 = 0.828

Allowances: Surface texture

Binder Abs. by Agg, Pvt Embedment

AST ABA AE

L/m L/m L/m

+ 0.1

+ 0.1, nil nil


BD L/m 0.828 + 0.1 + 0.1 = 1.028 adopt 1.0


- m2/m3 290

INFORMATION RETRIEVAL

Austroads (2002), Practitioners Guide to Design of Sprayed Seals Revision 2000 Method, Sydney, A4, 42pp, AP-T17/02

KEYWORDS: Surfacing; sprayed seal; pavement design; pavement testing; bituminous pavement; aggregate ABSTRACT: This report provides the details necessary for users to design a sprayed seal to the Austroads Sprayed Seal Revision 2000 Design Method. The method covers the use of: ! conventional bitumens ! polymer modified binders, and ! bituminous emulsions when used in single/single or double/double seals. The method is applicable to roads carrying up to 10,000 vehicles per lane per day. A number of worked examples are included to assist in the correct interpretation of the method.

AUSTROADS PUBLICATIONS

Austroads publishes a large number of guides and reports. Some of its publications are: AP-1/89 Rural Road Design AP-8/87 Visual Assessment of Pavement Condition Guide to Traffic Engineering Practice AP-11.1/88 Traffic Flow AP-11.9/88 Arterial Road Traffic Management AP-11.2/88 Roadway Capacity AP-11.10/88 Local Area Traffic Management AP-11.3/88 Traffic Studies AP-11.11/88 Parking AP-11.4/88 Road Crashes AP-11.12/88 Roadway Lighting AP-11.5/88 Intersections at Grade AP-11.13/95 Pedestrians AP-11.6/93 Roundabouts AP-11.14/99 Bicycles AP-11.7/88 Traffic Signals AP-11.15/99 Motorcycle Safety AP-11.8/88 Traffic Control Devices AP-12/91 Road Maintenance Practice AP-13/91 Bridge Management Practice AP-14/91 Guide to Bridge Construction Practice AP-15/96 Australian Bridge Design Code AP-17/92 Pavement Design AP-18/00 RoadFacts 2000 AP-22/95 Strategy for Pavement Research and Development AP-23/94 Waterway Design, A Guide to the Hydraulic Design of Bridges, Culverts & Floodways AP-26/94 Strategy for Structures Research and Development AP-C29/01 Austroads Strategic Plan 20012004 AP-G30/02 Road Safety Audit 2nd Edition AP-34/95 Design Vehicles and Turning Path Templates AP-36/95 Adaptions and Innovations in Road & Pavement Engineering AP-38/95 Guide to Field Surveillance of Quality Assurance Contracts AP-40/95 Strategy for Ecologically Sustainable Development AP-41/96 Bitumen Sealing Safety Guide AP-42/96 Benefit Cost Analysis Manual AP-43/00 National Performance Indicators AP-44/97 Asphalt Recycling Guide AP-45/96 Strategy for Productivity Improvements for the Road Transport Industry AP-46/97 Strategy for Concrete Research and Development AP-47/97 Strategy for Road User Costs AP-48/97 Australia at the Crossroads, Roads in the Community A Summary AP-49/97 Roads in the Community Part 1: Are they doing their job? AP-50/97 Roads in the Community Part 2: Towards better practice AP-51/98 Electronic Toll Collection Standards Study AP-52/97 Strategy for Traffic Management Research and Development AP-53/97 Strategy for Improving Asset Management Practice AP-54/97 Austroads 1997 Bridge Conference Proceedings Bridging the Millennia AP-55/98 Principles for Strategic Planning AP-56/98 Assessing Fitness to Drive AP-57 & 58/98 Cities for Tomorrow Better Practice Guide & Resource Document AP-59/98 Cities for Tomorrow CD AP-60/98 Guide to Stabilisation in Roadworks AP-61/99 Australia Cycling 1999-2004 The National Strategy AP-62/99 e-transport The National Strategy for Intelligent Transport Systems AP-64/00 Austroads 4th Bridge Conference Proceedings Bridges for the New Millenium AP-G65.1/01 Road Condition Monitoring Guidelines: Part 1 Pavement Roughness AP-G66/02 Asphalt Guide AP-G67/02 Travel Demand Management: A Resource Book AP-G68/01 Guide to Heritage Bridge Management AP-G69/02 Urban Road Design: A Guide to the Design of Major Urban Roads These and other Austroads publications may be obtained from:

ARRB Transport Research Ltd Telephone: +61 3 9881 1547 500 Burwood Highway Fax: +61 3 9887 8144 VERMONT SOUTH VIC 3131 Email: [email protected] Australia Website: www.arrb.com.au

or from road authorities, or their agent in all States and Territories; Standards New Zealand; Standards Australia & Bicycle New South Wales.

Sprayed Seal Manual 443_AP-T17

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