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Decorative Finish | Sweep Blasting | Thicker Galvanized Coatings | Galvanized Steel in contact with Timber | Steel Detailing | Safe Buildings | Imported Steel Products | Advantages of After Fabrication Galvanizing | Standards Update | Materials Handling & Conveyors | Lintels and Shelf Angles | Zinc for Human Health | Atmospheric Corrosion Resistance | Paint over Galvanizing | Abrasion Resistance | Use of Galvanized Reinforcement | Repair of Field Welds | Wet Storage Stain | Distortion | Thickness on Flame-Cut Edges | Coastal Construction
Safe Buildings
Structural Steel
Advisory Note
GEN/22/1
July 2002
Most residential / commercial buildings are primarily of bricks or concrete but
require the strategic use of steel for the critical linkage, strength and anchorage
required within building systems.
The Australia / New Zealand Standard series AS/NZS 2699:2000 Built in Components
for Masonry Construction, specifically covers such items and addresses their
reliable and proven durability.
This covers:
- Wall ties
- Connectors and accessories
- Lintels and shelf angles
These Standards have been revised as a reference to the masonry code AS
3700, during upgrading of the relevant codes mandated after the Newcastle
earthquake.
Steel corrosion protection for 50 years is a code requirement to ensure
safety, prevent brick or concrete cracking as rusted steel volume expands
x3 and to avoid the need for maintenance.
Building surveyors are already asked to accept responsibility for judging
the exposure severity of the building location, where the codes provide instructions
on levels of corrosion severity from R0 to R5.
Protective coating systems in the Standards, range from grit blasting and
3 coats of high performance paint APAS (formerly GPC) approved, to hot dip
galvanizing or stainless steel. However it appears that in some States the
commonest treatment is one coat of general purpose primer with a protective
life of 2-5 years.
Thus such steel work may seem in order for 6 years or so but there after
give rise to serious structural problems, which in many cases will be covered
and unseen until structural failure.
At a time when the cost of insurance cover and an inclination to consumer
litigation are increasing, we recommend that building surveyors seek documented
proof of compliance, before building certification
After Fabrication Galvanizing
The Best Insurance Policy for Steel
Standard AS/NZS 4680 aligned to ISO 1461 offers
- 170 years of use
- Service life of 30 to over 100 years
- Hardness exceeding mild steel
- Alloyed to steel substrate
- Competitive prime cost
- Construction efficiency
- Life cycle superiority
Reliability the policy with the best cover
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