Curious, powerful creatures<\/h2>\n
Midwest Constructors, LLC served as concrete contractor on the $26-million, 20,000-square-foot exhibit, which broke ground in September 2012. Crews from Prairie Yard 79 in Indianapolis provided 6 different mixes for the 3,700-yard project.<\/p>\n
\u201cPeople ask why we used concrete instead of materials you\u2019d find in the rainforest, such as wood,\u201d says\u00a0Daniel Overbey, director of sustainable design practices at Browning Day Mullins Dierdorf Architects. \u201cOne concern is sanitation, since federal standards for zoos require washable walls. But even more important is the orangutan\u2019s natural curiosity and strength. They\u2019ve been known to bend quarter-inch steel plate with their bare hands! We needed surfaces that could take a beating and keep the animals safe.\u201d<\/p>\n
Overbey worked with lead architect Jonathan Hess to shape the exhibit\u2019s features, including the network of towers, platforms and cables that lets the apes swing and climb up to 80 feet overhead, just as they would in the wild. Three enclosed \u201coases\u201d allow the orangutans to choose how and when they interact with peers while tempered, insulated glass in the indoor R. B. Annis Atrium puts them face-to-face with humans. Outside, visitors can see the animals in action from The Skyline, a 1,200-foot-long aerial cable ride that rings the exhibit.<\/p>\n
\u2018Not a straight wall \u200bin sight\u2019<\/h2>\n
![\"\"](\"https:\/\/www.prairie.com\/wp-content\/uploads\/sites\/4\/2024\/12\/tough-angle-walls.jpg\")
<\/p>\n
Construction challenges were as unique as the exhibit itself, says Midwest Constructors\u2019 Tony Kivett, who worked with Job Superintendent Tim Golden on the multi-year project.<\/p>\n
\u201cThese aren\u2019t typical structures in any sense of the word,\u201d Kivett explains. \u201cYou won\u2019t find a square, straight wall anywhere in sight.\u201d<\/p>\n
The 30-to-40-foot walls \u201clean outward, with numerous batters and folds,\u201d Golden says. \u201cBecause of this, the pours were done against and underneath the workers.\u201d<\/p>\n
Custom forms were precision-built on site. \u201cBecause of the angled walls, the construction technique was almost backwards \u2013 with shoring assembled first and forms attached last,\u201d says Golden.<\/p>\n
Dual-layer design poses tough problems<\/h2>\n
Creating the perfect habitat for the orangutans meant \u201can indoor environment just like we need, which means keeping warm even in the middle of an Indianapolis January,\u201d Overbey notes. The cast-in-place concrete walls provide R-20 insulation, nearly double the energy efficiency code requirement of 11.4.<\/p>\n
Project engineers favored a design often seen in pre-cast walls, featuring a 4-inch layer of insulation sandwiched between a 10-inch inner layer and a 6-inch outer layer of concrete.<\/p>\n
\u201cWe fabricated a split pipe for our pumps so both layers could be placed simultaneously,\u201d says Golden, \u201cbut during consolidation, we found we couldn\u2019t vibrate both sides of the wall in perfect unison, which made the insulation shift.\u201d<\/p>\n
Prairie experts addressed the problem by switching from 3\/4-inch to 3\/8-inch aggregate and adding a high-range water reducer, resulting in a 6-to-8-inch-slump mix that flowed smoothly through congested rebar and consolidated with greater ease.<\/p>\n
Crews then shifted their placement strategy, pouring the inner wall layer first. The insulation was affixed to the outer surface of this layer, with the final layer completed in 3 lifts.<\/p>\n
The custom wall mix \u201cfinished with a beautiful sheen, and we used it for the contour walls as well,\u201d Golden says.<\/p>\n
Color and fiber-enriched mixes for special needs<\/h2>\n
![\"\"](\"https:\/\/www.prairie.com\/wp-content\/uploads\/sites\/4\/2024\/12\/colored-concrete.jpg\")
<\/p>\n
Concrete helped solve other challenges throughout the exhibit. \u201cOrangutans like to play by breaking things, so all ductwork in the central atrium is on the people side. We used 4,000-psi concrete enriched with fibrillated fibers for the atrium slab, which safely encloses the conduit for all building systems,\u201d Overbey says.<\/p>\n
Outdoors, architects used an integrally colored mix \u2013 \u201cLava\u201d from the Prairie Pure Color line by Solomon Colors — to define the 6,000-square-foot plaza.<\/p>\n
The exhibit also contains many sustainable features, including an 8,000-square-foot green roof that will divert up to 70% of all storm water to a cistern for irrigation use. Wise storm water management is key, since the zoo lies within sight of the White River with its parking lot on a flood plain.<\/p>\n
<\/p>\n
A light of hope for the orangutans\u2019 future<\/h2>\n
As they live and play in their home-away-from home, the orangutans remind us of the pressing need to care for endangered species worldwide, zoo officials say.<\/p>\n
The exhibit\u2019s Beacon of Hope \u2013 a 150-foot spire topped with colored LED lights the orangutans activate with a special switch \u2013 signifies \u201cthere is still hope for the orangutans and that hope is centered on us,\u201d according to the zoo website.\u200b\u200b<\/p>\n
<\/p>","protected":false},"excerpt":{"rendered":"
\u200b\u200bThey\u2019re among our closest animal relatives, sharing nearly 97% of the same DNA. Yet, as experts at the\u00a0Indianapolis Zoo\u00a0point out, we have a lot to learn about orangutans. Zoo visitors streamed into a remarkable new exhibit last month, where 8 orangutans \u2013 one of the largest groups in any U.S. zoo \u2013 can climb, play […]<\/p>","protected":false},"author":1,"featured_media":2861,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2860","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/posts\/2860","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/comments?post=2860"}],"version-history":[{"count":0,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/posts\/2860\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/media\/2861"}],"wp:attachment":[{"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/media?parent=2860"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/categories?post=2860"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.prairie.com\/fr\/wp-json\/wp\/v2\/tags?post=2860"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}