An endangered species with only 1,830 adults in the world, the red-crowned crane is the second-rarest crane in the world. Also called the Manchurian crane or Japanese crane, it is a large East Asian crane known in some parts as a symbol of luck, longevity and fidelity. They are especially famous for their complex displays in which they bend down, graciously move their head and leap into the air. In South Korea, the red-crowned crane, which live in pairs and spend their whole life together, spends the winter in vast wetlands, the deep-water marshes.
Giant titanium zinc eggs adorn South Korean weir
It is the eggs of this rare, red-crowned crane that provided the inspiration for the large egg-shaped spheres on the Yeoju Ipo-gu weir in the Han River. The Han River, or Hangang, is a major river in South Korea, and the fourth longest river on the Korean peninsula after the Amnok, Tuman and Nakdong rivers. The river begins as two smaller rivers in the Eastern mountains of the Korean peninsula and then converge near Seoul.
The Yeoju Ipo-gu weir is part of a major project South Korea is implementing in an attempt to control the effects of climate change such as flooding and drought. By regulating its water management using weirs, increasing the height of dikes and dames in diverse rivers, South Korea is safeguarding the sites where the red-crowned crane spends winter.
Designed by Espace Architecture, South Korea, the project consists of a total of seven eggs, 52 feet long and 27 feet high. Covered with natural titanium zinc and mineral grey pre-weathered titanium zinc panels from NedZink BV, The Netherlands, the eggs reflect sunlight from afar. There are approximately 1,600 TiZn shingles/panels per egg, and each panel size was 1 1/2 feet by 1 1/2 feet. This resulted in approximately 5,000 pounds of zinc per egg, made up of 50% pre-weathered and 50% natural zinc. Yangjin Industry, South Korea, was the installer.
With its curved body, the eggs are an ideal shape for the shingle system rather than the flat lock panel system. The egg is made up of a steel frame of curved, round tubes and steel profiles that follow the contours of the outer shell. Wood paneling is applied to the frame and foils are added. The zinc shingles are hooked onto each other and secured to the substrate with clips. The shingles provide a raintight shell and are placed while the construction was still at ground level. After completion, the entire egg is placed on the concrete pillars by four lifting hooks.
Due to its eccentric shape, the zinc eggs offer a different appearance from each angle. “Contrasting the green hills and the clear water, the zinc eggs reflect the sunlight. In the evening, the artificial lightning offers a completely different picture,” says Erwin Smeets, business development director of NedZink. “Due to the craftsmanship of the zinc workers, this natural zinc material fits into the landscape and contributes to an environmentally friendly and responsible application.” The project was turned into an ecological tour de force that the local population can enjoy. Additionally, a recreation area has been established around the weir complex.
“The attractive interplay of both titanium zinc surfaces and the ornate light reflections offer an impressive image to the viewer,” adds Smeets. The natural zinc is used on the lower part and the mineral grey-colored zinc on the top. “The contrast between these two colors in combination with the shingles and the exceptional shape make this project a unique design.”