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A bracket system designed for longevity
By Les Boulton
Nickel Magazine, December 2009 -- A recently built temple in the
Philippine city of Cebu should last a minimum of 100 years, thanks to a novel structural bracket system
consisting of nickel-containing stainless steel.
Most anchor bracket systems are made from galvanized steel and last only about 50 years in the hot, humid
Philippine coastal environment. However, the Church of Jesus Christ of Latter-day Saints wanted the Cebu
Philippines Temple to stand at least 100 years, without concern that the external white granite slabs would
fall down because of corrosion to the support brackets. For this reason, brackets fabricated from Type 304
(S30400)
and Type 316 (S31600)
stainless steel were used.
Nickel-containing stainless steels are as strong as galvanized steel, and their mechanical properties are
structurally suited to the anchoring system used at the temple. There is an economic advantage as well: the
stainless steel anchors will cost less over the temple’s lifespan than if galvanized steel were used.
The temple designers are confident the steel anchor brackets will not corrode and cause cladding panels to
fall. Corroding steel anchors could also create unsightly staining on the white stone cladding whereas the
stainless steel anchors will not.
The Type 304 structural brackets and fixings are hidden behind the granite cladding in a cavity where
corrosion could develop on steel brackets. Type 316 stainless steel, which resists corrosion even better than
304, was used in the tall window flashings since they are especially vulnerable to the severe marine
environment.
Calibre Engineering of Auckland, New Zealand, designed and fabricated the stainless steel bracket system
to a high standard, says Michael Green, the firm’s design manager. Calibre cut the brackets and fixings to
shape with a laser cutter; then, after delivery to Cebu, they were fixed to the granite slabs and attached to
the concrete building.
The 100-year minimum lifespan is based on a design assessment using computer technology by Auckland-based
Predefine Ltd., Virtual Design Consultants. This assessment indicates that the cladding will be safe even in
severe weather.
Anzor Fasteners Ltd., also of Auckland, supplied fasteners made of nickel-containing stainless steel to
attach the anchor brackets to the granite panels and to the building structure. In all, 120 tonnes of
stainless steel were used in the construction of the anchor brackets, wind load support posts, and window
flashings combined. The Type 316 window flashings, some of which are as high as 12 metres, can withstand
strong winds.
Safely supported by the uniquely designed and corrosion-resistant nickel-stainless steel bracket anchoring
system, the white granite façade on the Cebu Temple will continue to look beautiful well into the next
century.
Photos: NZ Strong Construction Limited
Mike Green
NZ Strong Construction Limited
Aukland, NZ
Phone: 09 631 1165
Web site: www.nzstrong.co.nz
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