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Title / Explain the properties, selection, and effects of polymer-modified binders in hot mix asphalt
Level / 5 / Credits / 8
Purpose / This unit standard is for people in the bitumen industry, such as asphalt mix designers, who require advanced technical knowledge of polymer modified binders.
People credited with this unit standard are able to explain: the properties of polymer-modified binders used in hot mix asphalt, their selection, and the effects of using them.
Classification / Pavement Surfacing > Asphalt Surfacing
Available grade / Achieved
Explanatory notes
1The following requirements apply to this unit standard, and must be complied with:
AGPT04F-08 Guide to Pavement Technology Part 4F: Bituminous Binders, Austroads Guidelines available at
Chipsealing in New Zealand, New Zealand Transport Agency, available at ;
AAPA Code of Practice: Manufacture, Storage and Handling of Polymer Modified Binders, Australian Asphalt Pavement Association, available at
MS-2Mix Design Methods,Asphalt Institute, available at
AGPT04B-07 Guide to Pavement Technology Part 4B Asphalt (Austroads Guidelines), Austroads, available at
IG8 Asphalt Mix Design, Australian Asphalt Pavement Association,available at
Austroads Pavement Design: A Guide to the Structural Design of Road Pavements: New Zealand Supplement, Roading New Zealand, available at
Any requirements superseding any of the above will apply, pending the review of this unit standard.
2Polymer manufacturer’s guidelines and data sheets must be referred to and their recommendations incorporated in the use of polymers.
3Assessment against this unit standard may be based on evidence from workplace and/or provider contexts.
4Definitions
Company procedures refers to all documented policies, procedures and methodologies of the candidate’s employer at the time of training including but not limited to those relating to health, safety, environment, quality, and operations;
SMA means stone mastic asphalt.
Outcomes and evidence requirements
Outcome 1
Explain the properties of polymer-modified binders in hot mix asphalt.
Evidence requirements
1.1The properties of polymer modifiers, the forms in which they are supplied, and their effect on the physical properties of bituminous binders, are explained in accordance with Austroads Pavement Design.
Rangemodifiers – elastomers, plastomers.
1.2Effects of binders on the physical properties of hot mix asphalt are explained in accordance with Austroads Pavement Design.
Rangeeffects – upper, lower, and mid-point of modifier addition rates;
modifiers – elastomers, plastomers.
1.3Effects of adhesion agents on modified binders are explained in accordance with Austroads Pavement Design.
1.4Binder properties required to achieve specified pavement performance are identified and explained in accordance with Austroads Pavement Design.
Outcome 2
Explain the selection of polymer-modified binders in hot mix asphalts.
Evidence requirements
2.1Reasons for using polymer-modified binders are explained in accordance with Austroads Pavement Design.
Rangeincludes but is not limited to – suitability for purpose;
binders modified with – elastomers, plastomers.
2.2Suitability of polymer-modified binders is explained, taking into account pavement conditions and site requirements, in accordance with Austroads Pavement Designand company procedures.
Rangeconditions – traffic, texture, cracking, flushing, deflection, pretreatment requirements.
2.3Benefits of binders on types of hot mix asphalt are explained in accordance with Austroads Pavement Design.
Rangetypes – dense-graded, open-graded, SMA.
2.4Binder selection is explained for at least three actual situations in accordance with Austroads Pavement DesignandAGPT04B-07.
2.5Processes and procedures for maintaining binder properties and quality are explained in accordance with the AAPA Code of Practice.
Rangeprocesses include but are not limited to – mixing, pumping, handling, storage temperatures, storage time.
Outcome 3
Explain the effects of using polymer-modified binders in hot mix asphalts.
Evidence requirements
3.1Effects of modified binder on resilient modulus, dynamic creep, and fatigue are explained in accordance with theMS-2 Mix Design Methods.
3.2Effects on the Marshall method of mix design are explained in terms of adjustments required and interpretation of results.
3.3Effects on hot mix asphalt mixing, handling, and storage are explained in accordance with theMS-2 Mix Design Methodsand company procedures.
3.4Effects are explained in terms of construction temperatures.
Rangetemperatures – transportation, laying, compaction.
Replacement information / This unit standard replaced unit standard 17673.Planned review date / 31 December 2016
Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 27 October 2005 / 31 December 2013
Review / 2 / 15 March 2012 / N/A
Consent and Moderation Requirements (CMR) reference / 0101
This CMR can be accessed at
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.
Comments on this unit standard
Please contact Infrastructure if you wish to suggest changes to the content of this unit standard.
Infrastructure ITOSSB Code 101813 / New Zealand Qualifications Authority 2018