Availability & Versatility
Hot-dip galvanized (HDG) steel is versatile and readily available. A wide variety of shapes and sizes ranging from small nuts, bolts, and fasteners to larger structural pieces, to even the most intricately detailed artistic pieces, can be galvanized. Because of the total immersion process, even complex fabrications can be coated entirely for corrosion protection. Many corrosion protection methods depend on proper temperature and humidity conditions for correct application. However, because hot-dip galvanizing is a factory controlled process, it can be accomplished 24/7/365 rain or shine. Zinc solidifies upon withdrawal from the bath, so there are no delays for curing; and galvanized steel could realistically be galvanized, shipped to the site, and erected on the same day. On the other hand, if the galvanized material does not need to be installed immediately, it is easily stored outside, as UV rays do not degrade the coatings integrity.
As North America continues to strive for sustainable development, the same thinking should be applied to the materials used in construction. Another characteristic of zinc, making it ideally suited for this job is its abundance. The main materials used in the galvanizing process, zinc and steel are common; in fact, zinc is the 24th most abundant material in the earths crust, and iron is the 4th. Zinc and steel are also both 100% recyclable without the loss of any chemical or physical properties steel is the most recycled material in the world.
Zinc is a natural element found in air, soil, and water. Approximately 5.8 million tons of zinc are cycled through the atmosphere annually through natural phenomena. Zinc is also common and essential to life. Zinc is found in a number of products we use daily such as cosmetics, tires, cold remedies, baby creams to prevent diaper rash, treatments for sunburns, and sunscreens. In fact, zinc oxide blocks more UV rays than any other single ingredient used in sunscreen. Furthermore, we all require zinc to live as it helps with regular functions such as vision, reproduction, digestion, and breathing.
Efficiency & Safety
With galvanized steel, you can do more with less. Because of the high strength-to-weight ratio, specifying projects with steel saves materials and energy. In fact, on average one ton of steel provides the same strength as 8 tons of concrete, and according to the World Steel Association, the strength-to-weight ratio minimizes substructure costs and can also save money on transportation and handling. In addition to the abundance and quick turnaround time, galvanized steel also facilitates the expansion of existing structures due to its flexibility and stockability. Galvanized steel members are easy to retrofit and expand by welding, bolting, and/or splicing of existing vertical and horizontal structural elements and adding reinforcement. Adding to existing structures allows maximum efficiency of available space. Steel members are lighter than many other materials but still provide great strength, so expansion within the same footprint is possible.
Furthermore, because of hot-dip galvanized steels durable, maintenance-free nature, elements can be stockpiled outside for years without compromising the zinc coating and its corrosion protection. The zinc coating of HDG is unaffected by UV rays, extreme temperatures, rain, snow, or humidity, so with proper storage it is simple to keep an inventory on-hand for quick replacement in an emergency. Stocking frequently used parts until they are needed saves time, and if bought when prices are low, saves money.
Structural safety and stability are critically important to the integrity of steel construction, and cannot be maintained if the structure has been weakened by the ravages of corrosion. Hot-dip galvanized steel pieces which remain corrosion resistant for decades preserve the structural integrity of steel construction and protect against disaster.
One area of safety where hot-dip galvanized steel provides advantages is in areas of seismic activity. Steel elements are more ductile and lighter, reducing the inertia effects of seismic loading. Able to bend within reason without breaking, the tensile strength of hot-dip galvanized steel can protect structures from damage or even total failure during seismic activity.
Versatility Case Studies
Hambro Portable Parking System - St. Lambert, QC 2010
A gleaming utilitarian marvel, the Hambro Modular Parking System is an ingenious construction with wide-reaching market implications. The system is a portable parking structure comprised of a parking deck and ramp, rails, and fencing elevated on support columns, all assembled over an existing parking lot to increase the number of usable parking spaces. The moveable structure offers the flexibility to resolve issues of limited space for parking, typically encountered in urban areas. The parking system can be used to alleviate pressure on popular parking lots, or serve as a temporary solution when part of a lot is taken out of commission.
The entirety of structure has been hot-dip galvanized, top-to-bottom, including everything from the deck panels and railings, to the fencing, supports and railings. It was a logical choice to utilize galvanized steel throughout the system, as these modules must be able to stand strong and corrosion free against the abuses of steady traffic and corrosive environment. The abrasion resistance, maintenance-free nature, and sustainability of galvanized steel made it the ideal construction material for this project. Because of the portable nature of the structure, the steel will be exposed to rough handling during transport and likely during assembly as well. A tough, durable corrosion protection system was necessary to preserve the attractive metallic aesthetic of the parking structure, which will be visible in close proximity due to the intended public use. Not only does the galvanized steel provide superior protection from the inevitable exposure to corrosive elements and superficial damage, it does while remaining maintenance-free for 75 years or more. This means none of the indirect costs of routine maintenance will be incurred the structure will not need to be taken out of commission for routine maintenance.
The concept of the portable parking system offers new and exciting market potential highlighting the inherent qualities of galvanizing, including durability, abrasion resistance, and sustainability. The aging urban infrastructure of our inner cities promises many more applications for this structure, and the use of hot-dip galvanized steel guarantees the structure will stand strong, corrosion-free, to fulfill its purpose for generations to come.
Denver Judicial Center - Light Chamber - Denver, CO 2010
With gracefully arched petals blooming skyward, the Light Chamber sculpture blossoming at the entrance of the Denver Justice Center utilizes organic curves and natural materials to generate a sense of airy, natural lightness and movement. Artist Dennis Oppenheim, who has incorporated galvanized steel in several outdoor artistic displays, wanted to create a free-flowing sculpture of leaves and flowers to symbolize the wide variety and multitude of decisions made in the judges chambers. Light Chamber was developed in the hope of creating a vibrant city plaza for visitors and pedestrians, as well as a visual escape for workers of the Justice Center. The prominent and visual nature of the piece warranted the best corrosion protection system available to prevent the unsightly scarring and damage of rust stains.
All components of the main structure totaling more than 29 tons of steel were galvanized to ensure the 45-foot tall outdoor display would remain stately and corrosion free for generations. The durable barrier protection of the zinc coating will protect the piece from the harsh sun and exposure to snow and rain, while the cathodic protection of the galvanized still will protect the piece from any nicks and scratches. All this will be done with no required maintenance for 75 years or more ideal for maintaining low cost.
The final appearance of the sculpture was an appealing, natural and consistent silvery gray that blends into the surrounding city elements, while allowing the organic shape and structure of the piece to stand out amid the straight-edged buildings surrounding it. With hot-dip galvanized steel, this piece will stand tall and lovely, unaffected by the ravages of corrosion, for decades of decision-making.