AB-Triple Road Train
FACT SHEET MR 1574 12/15
This fact sheet provides information on the expanded route access for AB-triple road train (formally
known as an AB-double in South Australia) and the load limits operating under permit within South
Australia.
A review of the access conditions for AB-triples operating under the Heavy Vehicle National Law
(HVNL) in South Australia has been undertaken and access for these combinations has been expanded
to include operation at Concessional Mass Limits (CML) and reduced Higher Mass Limits (HML) under
a Class 2 permit issued by the National Heavy Vehicle Regulator (NHVR).
Eligible Vehicles
AB-triples which meet the following criteria are eligible to apply for a permit to operate at the Gross
Combination Mass (GCM) limits for General Mass Limits (GML), CML and reduced HML operation:
Dimension Limits
 Length: 36.5 metres
 Width: 2.5 metres
 Height: 4.3 metres
Gross Combination Mass Limits
13 axles – 5 axle prime mover and
semitrailer combination, 2 axle converter
dolly and tri / tri B-double trailer
GCM
No steer axle exemption
GML
95.5t
CML
97.5t
HML
102.0t
With steer axle exemption
96.0t
98.0t
102.5t
13 axles – 6 axle prime mover and
semitrailer combination, 2 axle converter
dolly and tri / bogie B-double trailer
GCM
No steer axle exemption
GML
95.5t
CML
97.5t
Reduced HML
100.5t
With steer axle exemption
96.0t
98.0t
100.5t
14 axles – 6 axle prime mover and
semitrailer combination, 3 axle converter
dolly and tri / bogie B-double trailer
GCM
No steer axle exemption
GML
99.0t
CML
101.0t
Reduced HML
103.8t
With steer axle exemption
99.5t
101.5t
103.8t
14 axles – 6 axle prime mover and
semitrailer combination, 2 axle converter
dolly and tri / tri B-double trailers
GCM
No steer axle exemption
GML
99.0 t
CML
101.0t
Reduced HML
105.4t
With steer axle exemption
99.5t
101.5t
105.4t
15 axles – 6 axle prime mover and
semitrailer combination, 3 axle converter
dolly and tri / tri B-double trailers
GCM
No steer axle exemption
GML
102.5t
CML
104.5t
Reduced HML
108.0t
With steer axle exemption
103.0t
105.0t
108.0t
Minimum Axle Spacings (metres)
13 axles – 5 axle prime mover and semitrailer
combination, 2 axle converter dolly and tri /
tri B-double trailer
Axles
Minimum Axle Spacings
1 – 13
27.7m
2 – 13
25.7m
2–5
6.8m
4–7
6.8m
6 – 10
8.0m
8 – 13
9.2m
13 axles – 6 axle prime mover and semitrailer
combination, 2 axle converter dolly and tri /
bogie B-double trailer
Axles
Minimum Axle Spacings
1 – 13
27.7m
2 – 13
25.7m
2–6
8.0m
4–8
8.0m
7 – 11
8.0m
9 – 13
8.0m
14 axles – 6 axle prime mover and semitrailer
combination, 3 axle converter dolly and tri /
bogie B-double trailer
Axles
Minimum Axle Spacings
1 – 14
28.8m
2 – 14
26.8m
2–6
8.0m
4–9
9.2m
7 – 12
9.2m
10 – 14
8.0m
14 axles – 6 axle prime mover and semitrailer
combination, 2 axle converter dolly and tri /
tri B-double trailers
Axles
Minimum Axle Spacings
1 – 14
28.8m
2 – 14
26.8m
2–6
8.0m
4–8
8.0m
7 – 11
8.0m
9 – 14
9.2m
15 axles – 6 axle prime mover and semitrailer
combination, 3 axle converter dolly and tri /
tri B-double trailers
Axles
Minimum Axle Spacings
1 – 15
30.0m
2 – 15
28.0m
2–6
8.0m
4–9
9.2m
7 – 12
9.2m
10 – 15
9.2m
Why reduced HML?
The eligible AB-triples operating in South Australia were assessed against the Performance Based
Standards (PBS) template vehicle approved for access to the Level 3A network. The assessment
showed that the AB-triples listed above have a more severe impact on structures as compared with
the PBS template vehicle due to the differences in axle spacing and loads. As a result of this, the
maximum HML cannot be offered to vehicles operating under the pre-approval provided to the
Regulator.
Note: In order to obtain mass limits greater than those outlined above, the vehicle combination would
need to be assessed through the PBS process to demonstrate that it meets the necessary standards
and performance criteria and to verify the vehicle complies with the Tier 1 bridge formula at 110
tonnes.
Approved areas or routes
An AB-triple is permitted to operate on the PBS Level 3A network at GML, CML and in some cases at
reduced HML on the South Australian RAVnet Map System (http://www.dpti.sa.gov.au/ravnet) and in
accordance with any conditions or limitations for those routes or the mass limits specified in the
permit.
How to apply
Operators with eligible vehicles are able to access this initiative via a permit issued by the NHVR.
For more information on the NHVR
Call: 1300 MYNHVR (1300 696 487)
Visit: www.nhvr.gov.au
Email: [email protected]
For more information on this fact sheet, contact DPTI
Call: 1300 882 249
Visit: www.sa.gov.au/heavyvehicles
Email: [email protected]