CSTR: Part D32 Design – Traffic Signals
Edition: Nov 2014
PART D32
DESIGN - TRAFFIC SIGNALS
CONTENTS
1.
2.
3.
4.
5.
6.
7.
8.
General
References
Design Volumes and Vehicles
.
.
.
Approval of Traffic Control Devices
Records
1.
GENERAL
This Part specifies the requirements for the design of traffic signals. The design of conduits for traffic signals must
comply with Part D30 "Design – Conduit Systems".
Where the traffic signal design is required to be approved by DPTI, that approval will be provided by the DPTI
Traffic Operations Group, Norwood Office.
Refer to: http://www.dpti.sa.gov.au/documents/contractsandtenders/specifications/general for a list of traffic signal
products approved by the Principal. The Contractor may submit a request for the approval of additional products.
2.
REFERENCES
Unless specified otherwise, all design must be undertaken in accordance with TS – 100 “Traffic Signal Design
Standard”, available from: http://www.dpti.sa.gov.au/standards.
3.
DESIGN VOLUMES AND VEHICLES
Current Traffic Volumes and Projected Traffic Design Volumes (2021 and 2031) are included in Appendix xxxx.
The Contractor must design the traffic signals to accommodate the Projected Traffic Design Volumes.
The design vehicle is specified in Part D21 “Design – Road Geometry”.
4.
TRAFFIC MODELS AND DATA PROVIDED
The Principal has developed mesoscopic Aimsun model covering the majority of the Adelaide metropolitan road
network, with a calibrated 2014 base model that spans the following area:
(a) North – Port River Expressway and Salisbury Highway;
(b) East – Churchill Road, Park Terrace, Port Road and Railway Terrace;
(c) South – Anzac Highway; and
(d) West – Marion Road, Holbrooks Road, East Avenue, David Terrace and Hanson Road
From this, the following linear Aimsun microsimulation models, spanning from the South Road/Regency Road
through to South Road/West Thebarton Road/Ashwin Parade, have been developed for use by the Contractor:
(a) Construction model
(b) 2021 reference design model
(c) 2031 North-South Corridor model
These microsimulation models, and their associated origin-destination matrices, are provided in Appendix 13.
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5.
TRAFFIC MODELLING
5.1
Traffic Management During Construction
CSTR: Part D32 Design – Traffic Signals
The construction traffic model is to be used by the Contractor to analyse the impacts of workzone traffic restrictions
during the various construction stages.
In the mesoscopic model the following road network upgrades have been included. These upgrades will be
implemented prior to the major roadworks construction on the Torrens Road to River Torrens Project commencing:
(a) South Road/Richmond Road intersection upgrade and Richmond Road widening
(b) James Congdon Drive duplication
(c) Park Terrace/Fitzroy Terrace/Torrens Road widening
(d) South Road/Ashwin Parade/West Thebarton Road intersection upgrade
The construction model uses 2014 volumes, and the origin-destination matrices for the microsimulation model’s
sub-area have taken into consideration traffic redirection in the mesoscopic model as a result of the upgrades
above.
Provision of the construction stage model shall constitute a HOLD POINT.
5.2
2021 Reference Design Model
The 2021 microsimulation model includes the reference design within the model area. The Contractor must model
network performance in accordance with the performance indicators specified in Clause 8.
5.3
2031 Projected Model
The 2031 microsimulation model includes the North-South Corridor as being fully implemented. The Contractor
must design and document how implementation of the Torrens Road to River Torrens Project scope can be
expanded to the full North-South Corridor and cater for 2031 design volumes with minimal redundant work. The
Contractor must model network performance in accordance with the performance indicators specified in Clause 8.
6.
NETWORK PERFORMANCE ANALYSIS
The Contractor must use Aimsun to analyse network, intersection and interchange performance during AM and PM
peaks for 2021 and 2031. This microsimulation modelling must be in accordance with the DPTI AIMSUN Model
Development Manual (provided in Appendix 13) and in the same linear sub-area as the reference design model that
has been provided.
The Contractor must demonstrate that the design performs no worse than the reference design in both 2021 and
2031.
Provision of the network performance analysis shall constitute a HOLD POINT. The models must be provided to
the Principal in native file format.
Performance indicators must include:
(a) Overall network delay time
(b) Queue lengths
(c) Number of stops per vehicle
(d) Average speed
(e) Travel time – average and for key routes
(f) Intersection delay
7.
INTERSECTION ANALYSIS
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CSTR: Part D32 Design – Traffic Signals
There are several performance measures of intersection analysis that must be achieved. No intersection movement
shall have a degree of saturation greater than 0.95. The 95th percentile queue lengths for each intersection lane
must not exceed the storage length of the lane. For continuous lanes, the 95th percentile queue length must not
extend to any adjacent signalised intersection or pedestrian crossing. For closely-spaced intersections,
consideration must be given to the expected lane utilisation distribution as a result of upstream and downstream
turning movements. Justification must be provided, whether software defaults or user-specified lane distributions
are used. Justification could be in the form of existing lane distributions from SCATS or it could be modelled in a
micro-simulation software package such as Aimsun.
Intersections within the study area must all use the same cycle length to ensure that signal coordination can be
achieved. This must be based on the intersection that requires the highest cycle length in the study area. Minor
intersections may operate at half of the highest cycle length if it can be demonstrated that the performance measures
can be achieved and double-cycling does not impact on signal coordination.
Intersection layouts must be designed to provide the most flexible signal operation as possible. Opposed right turns
should be designed to run concurrently to allow diamond right turn operation. Shared lanes should not be used
unless it can be clearly demonstrated that the shared turns can only run in the same signal phases. Split-approach
phasing should be avoided unless it can be clearly demonstrated that alternative phasing arrangements will have a
significant impact. Right turns must be fully controlled and the filtering of right turns is not permitted.
Intergreen times must ensure that vehicles have sufficient time to safely clear the conflict zones of any movements
that may run in the following signal phase. Intersection phase times need to take into consideration the impact of
pedestrian movements, particularly if they require longer phase times than those needed for vehicle traffic . In these
cases, the likelihood of the pedestrian phase running needs to be averaged across the peak hour and the phase time
fixed to this value.
8.
OPERATIONAL ANALYSIS
8.1
General
The traffic signals analysis must include:
(a) a base case (calibrated and validated) for comparison with the design solutions, which is constructed from
existing intersection geometry and operational parameters;
(b) Analysis of the design solution with 2021 design volumes;
(c) Analysis of the design solution with 2031 design volumes, as a component of the broader North-South
Corridor; and
(d) An assessment of the impacts on intersection and network performance of proposed traffic management
strategies to be adopted during the construction phase of the project. Analysis will include all major
construction staging of traffic signal arrangements, including a detailed assessment of the performance of
the proposed interim traffic signal operations.
This must be fully documented in the Traffic Signal Operation Performance Report.
8.2
Traffic Signal Coordination
The Contractor must use TRANSYT for the optimisation of traffic signal co-ordination. This modelling must be
undertaken in accordance with the DPTI: Traffic Modelling Guidelines – TRANSYT-15 (provided in Appendix 13).
The modelling should extend to cover current link chains and sites that need to be added for the purposes of
construction traffic management or due to changes in traffic patterns post completion. The extent of the TRANSYT
model(s) must be:
(a) Port Road – from TS3090 Port/Gaol to TS039 Port/Kilkenny;
(b) Grange Road – same model as Port Road as TS152 Adam/Manton links to TS037 Port/Park/Adam and
TS051 South/Grange links to TS038 South/Port; and
(c) Torrens Road – from TS035 South Road to TS169 Rosetta Street, and from TS020 Woodville Road to
TS022 Regency Road, and from TS021 Torrens/Hanson to TS003 Hanson/First
9.
TRAFFIC SIGNAL HARDWARE
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CSTR: Part D32 Design – Traffic Signals
Edition: Nov 2014
DPTI approved traffic signal products must be used. A list of approved products is included in the DPTI Approved
Products List, available from: http://www.dpti.sa.gov.au/documents/contractsandtenders/specifications/general. The
Contractor may submit a request for the approval of additional products.
9.1
Traffic Signal Wiring
In addition to Clause 7.4 of TS – 100 “Traffic Signal Design Standard”, the supply of a cable connection chart for
approval of the Principal will constitute a HOLD POINT.
9.2
Traffic Signal Controller
In addition to Clause 7.7 of TS – 100 “Traffic Signal Design Standard”, details of the Contractor proposals in
regard to the traffic signal controller products are to be included in the Traffic Signal Operation Performance
Report at the 30% design stage. The traffic controller specified must be vehicle actuated and vehicle actuation must
be provided to enable SCATS® operation.
9.3
Video Surveillance (CCTV cameras)
Video surveillance (CCTV) shall be provided at all signalised intersections included in the Works, for all legs of
each intersection.
9.4
Provision of Telecommunications for SCATS®
9.4.1
SCATS® Communication
Notwithstanding Part 255, the optic fibre connection must be via the DPTI optic fibre cable network.
9.4.2
Linking Control Module
The Contractor is responsible for the procurement, installation and programming of the Linking Control Module
(LCM). The LCM must be an approved product.
10.
APPROVAL OF TRAFFIC CONTROL DEVICES
Traffic signals are traffic control devices requiring approval pursuant to the Road Traffic Act 1961 (SA). The
Contractor is responsible for ensuring that the traffic signals are properly approved by DPTI. A minimum notice of
8 weeks prior to switching on new traffic signals, or changing the personality(s) in existing traffic signals is required
to obtain this approval.
11.
RECORDS
The following records must be provided to the Principal:
Drawings
The drawings described in TS 100 “Traffic Signal Design Standard”.
As constructed drawings.
Reports
The reports described in TS 100 “Traffic Signal Design Standard”.
Implementation Records
Approval of Traffic Control Devices pursuant to the Road Traffic Act.
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