What is HIGH DURABILITY HD?

Our HD products provide the same structural capacity as our standard floor deck range but come with an enhanced metallic coating with a unique composition of Zinc, Aluminium and Magnesium.

Benefits:

• Improved corrosion resistance with similar coating thickness
• Suitable for aggressive environments (e.g. chloride and highly alkaline)
• Excellent cut-edge protection (self healing effect)

The difference in coating

The dense and compact nature of the enhanced metallic coating used on the HD products (refer Fig 13.1a (left image)) provides superior corrosion resistance compared to the more porous structure provided by our standard Hot Dip Galvanised Z275 coating (refer Fig 13.1a (right image)).

Also refer to Sections;

• 7.4 - Durability
• 7.5 - Aggressive environments
  

Corrosion behaviour - Salt spray test

The samples in Fig 13.1b and graph (refer Fig 13.1c) show comparison between the two coating options under salt spray test (highly chloride environment) carried out in the lab on ZM310g/m2. Time scales for samples shown in Fig 13.1b are:

• HD after 34 weeks
• Standard Zinc after 6 weeks

Where could HD deck be used?

• External locations
• Car Parks
• Areas identified as aggressive environments (i.e. category C2-C3 or above)

Composite beams

Thru-deck stud welding with HD:

• Suitability of stud welding tested in accordance with BS EN ISO 14555.
• Weld settings (WPS) for welding current, time, protrusion and lift available.
• Un-painted top flanges still required (as always).

Un-painted top flanges not suitable for the environment?

Consider pre-studded beams (painted) and single span deck sheets with crushed ends (refer to Section 13.2 - Crushed ends deck sheets).

More information available on our website regarding:

• Refer to SMD High Durability Coating for more information

• Design Considerations when using steel deck construction for car parks

• Durability of Steel Deck Composite Floors