A key element of the Monash Freeway Upgrade is the installation of eleven gantries to support the electronic signs that form part of the state-of-the-art freeway management system. These gantries measure up to 55 metres in length and weigh up to 50 tonnes.
Constructed of mild steel, the gantries have external surfaces that require lasting protection from the elements.
A Tried, Tested and Certified Coatings System
To ensure long-term durability, Dulux® Protective Coatings' specialist, Steve Kraljevic recommended a three-coat protective system, that conformed with the DoT 631 requirements:
• 1st coat: Dulux® Zincanode® 402 @ 75-microns (µm) DFT
• 2nd coat: Dulux® Durebild® STE MIO @ 150-microns (µm) DFT
• Topcoat: Dulux® Weathermax® HBR @ 75-microns (µm) DFT
Expertly spray coated prior to installation by Blastmasters, the system meets stringent Australian and New Zealand standards (AS/NZS 2312.1:2014) for Category C3 medium corrosivity environments and exceeds the required standard for protecting external steelwork (PUR4).
"There's no doubt that this coating system will provide long lasting, highly durable protection against atmospheric corrosion," Steve says.
In addition, each of the products used in the system was assessed and confirmed to meet all requirements under the Australian Paint Approval Scheme (APAS), a third-party conformity and product pre-qualification scheme that tests and certifies all types of surface coating materials and associated products.
"It is a requirement for all Victorian Department of Transport projects to use APAS certified coatings in new construction work," Steve explains. "We have APAS certification on our intermediate and topcoats in the full range of product colours and bases for products used in this project."
The Perfect Primer for Heavy Duty Infrastructure
Often used in the protection of hardworking infrastructure such as power generation plants and oil refineries, Zincanode 402 is a two pack zinc-rich epoxy that provides high cathodic corrosion resistance.
"Zincanode 402 offers relatively high film builds without mud cracking and its rapid dry and overcoat times is a huge advantage for project managers who are pressed to meet tight deadlines," Steve says.
A High-Performance Coating for Australian Conditions
It is the high level of micaceous iron oxide (MIO) in Durebild STE MIO that makes it such an effective protective coating.
An anti-corrosion pigment, MIO is used to protect high-value steel assets such as the Sydney Cricket Ground and Melbourne's West Gate Bridge. But, as Steve points out, it's not just bridges that need the best protection from corrosive environments.
"All steel that is exposed to UV radiation, moisture, abrasion and chemicals can be made more durable with a protective MIO coating," he says.
"One of the key advantages of Durebild STE MIO is that it offers a fast-curing option," Steve says. "When used with Quickturn® Hardener, Durebild® STE MIO can be overcoated within 9 hours."
An Ideal Topcoat for Gloss, Colour and Graffiti Resistance
Selected for its excellent gloss and colour retention even after extended exposure to the elements, Weathermax HBR also provides an effective barrier against graffiti and stands up to repeated cleaning by most graffiti removal agents.
Tintable in over 5,000 shades, Weathermax HBR is a popular topcoat for asset managers seeking lasting colour in harsh environments with extreme UV exposure.
"Weathermax HBR is a high durability, low maintenance product, making it perfect for infrastructure projects such as this where you want to minimise ongoing maintenance," Steve says.
