6Mechanical, physical, enclosure and mounting requirements#
6.1General#
The mechanical and physical requirements defined in MRTS201 General Equipment Requirements and MRTS61 Gantries and Support Structures for Road Signs, Tolling Systems and ITS Devices apply to work provided under this Technical Specification. Additional mechanical and physical requirements for equipment provided under this Technical Specification are described below.
6.2Design life#
Unless otherwise specified, the design life of the TVMS components shall be in accordance with Clause 2.2 of AS 4852.2.
6.2.1General mounting requirements#
The display enclosure shall be capable of being mounted on a vehicle, a trailer or a concrete block support structure in a location consistent with QGTM Part 10. The mounting structures supporting the TVMS shall be designed for the site conditions in which they are intended to be used.
The structure shall be designed in accordance with MRTS61 Gantries and Support Structures for Road Signs, Tolling Systems and ITS Devices, AS/NZS 1170.1 and AS/NZS 1170.2 when installed with all supporting hardware and accessories used to operate the signs, including the solar panels, where fitted.
Vehicle, trailer and / or concrete block support structure design documentation showing compliance with this Technical Specification and certified by a RPEQ, shall be submitted to the Principal’s representative for review and acceptance. Hold Point 4
6.2.2Vehicle mounts#
The vehicle on which the TVMS is mounted shall conform to the requirements of the host vehicle specified in the Queensland MUTCD Part 3 and this Technical Specification. Where there is discrepancy between the Queensland MUTCD Part 3 and this Technical Specification, regarding the host vehicle, the Queensland MUTCD Part 3 takes precedence. If required, vehicle-mounted TVMS shall be fitted with solar panels.
6.2.3Trailer mounts#
Where the TVMS is mounted on a trailer, the sign and solar panel array shall have a mechanical system which allows the sign and solar panel to be safely secured to the trailer for transportation. The mechanical system shall also allow for the sign and solar panel to be safely erected onsite to ensure the sign is clearly visible to motorists and that the solar panels can be adjusted to ensure optimum solar exposure and maximum energy generation in any part of the state of Queensland. The mechanical systems shall ensure that the sign cannot rotate due to wind gusts up to the ultimate wind speed the structure is designed. The trailer shall comply with the applicable Australian Design Rules and shall be suitable for registration in accordance with the statutory requirements of the state of Queensland. All metal surfaces shall be painted in the range of high visibility colours from X15 Orange to X13 Marigold as specified in AS 2700.
6.2.4Concrete block mounts#
The final design documentation of concrete block mounts shall include the location and type of mounting structure to be provided to mount each TVMS and the Contractor shall not commence fabrication of the footing and support structure until that final design documentation has been accepted by the Principal or their delegate.
6.3Exterior finish and surfaces#
The surface finishes shall comply with AS 4852.1 Section 3.1.2 with all external surfaces apart from the front face painted in the range of high visibility colours from X15 Orange to X13 Marigold as specified in AS 2700.
6.4Front cover#
6.4.1Design#
The protective front cover shall be fitted to the display enclosure to form a viewing window. The front cover material shall be a single, clear Lexan® polycarbonate sheet, or equivalent, with UV-resistant non-reflective finish. The sheeting shall be manufactured from sign-grade material SG300 with a thickness at least equal to that recommended by the manufacturer, and in all cases, at least 4.5 mm. The viewing window shall be such that when installed, the sides and bottom edges of the display face are fully visible at viewing angles of ± 45° (horizontal) and ± 30° (vertical) to the axis perpendicular to the front plane of the display.
6.4.2Retention method#
The front cover shall be able to be removed from outside the TVMS for maintenance without requiring removal of internal components. Fasteners and retaining cover strips shall be easily accessible.
The front cover retention and seal design shall allow for thermal expansion properties of the front cover material. The front cover surrounding framework and cover strips shall provide the required weather proofing and strength for both positive and negative wind pressures.
6.5Condensation prevention#
A mechanism shall be provided to prevent condensation on the inside surface of the front cover. One way this could be done is by using a demister or other dehumidifying solutions.
6.6Enclosures#
All telecommunications equipment, including the FP and the TVMS controller associated with the TVMS, may be installed in a suitable roadside enclosure, being either:
- a) a ground-mounted field cabinet complying with requirements of MRTS226 Telecommunications Field Cabinets
- b) a traffic signal controller, or
- c) an integral enclosure, or display enclosure, complying with the requirements of MRTS201 General Equipment Requirements installed on the TVMS mounting structure.
6.6.1Display enclosure#
The sign enclosure shall house the DU and associated control electronics, and comply with the requirements of MRTS201 General Equipment Requirements. The sign enclosure shall be made of marine-grade aluminium which complies with AS 4852.1 Clause 3.1.1. The display enclosure shall provide a degree of protection of not less than that required for the classification of IP65 in accordance with AS 60529 in normal service. Access shall be provided to allow TVMS maintenance and configuration. The door arrangement shall be compatible with the mounting structure members. The mounting structure shall comply with the requirements of MRTS201 General Equipment Requirements and MRTS61 Gantries and Support Structures for Road Signs, Tolling Systems and ITS Devices.