1 00:00:03,603 --> 00:00:06,006 [Jay] How do you crack open an apartment building 2 00:00:06,874 --> 00:00:08,843 and create a man-made canyon inside? 3 00:00:09,777 --> 00:00:13,146 There were moments where I did not think it was going to work, 4 00:00:13,246 --> 00:00:15,982 and I did not think that we would be able to pull it off. 5 00:00:17,017 --> 00:00:18,585 [Jay] What happens when you build 6 00:00:18,686 --> 00:00:20,520 a 630-foot icon... 7 00:00:21,821 --> 00:00:23,423 ...without a safety harness? 8 00:00:24,391 --> 00:00:27,194 I honestly didn't know how dangerous it was 9 00:00:27,528 --> 00:00:30,697 until I took my first step up to that platform. 10 00:00:32,165 --> 00:00:34,835 [Jay] And how do you construct dazzling new offices 11 00:00:34,935 --> 00:00:36,971 on a tiny scrap of contaminated land 12 00:00:37,271 --> 00:00:39,372 surrounded by water? 13 00:00:40,941 --> 00:00:42,610 It's impossible, what we've done. 14 00:00:42,710 --> 00:00:44,211 Absolutely impossible. 15 00:00:44,845 --> 00:00:47,381 [serious guitar music] 16 00:00:47,514 --> 00:00:50,684 [Jay] This is the age of the extraordinary. 17 00:00:51,951 --> 00:00:55,155 [Amma] It's totally different from anything around it. 18 00:00:55,256 --> 00:00:58,024 It's like a visitor from another planet. 19 00:00:58,124 --> 00:01:00,694 [dramatic music] 20 00:01:00,794 --> 00:01:02,262 [Jay] Where ingenious engineers 21 00:01:02,396 --> 00:01:04,531 have unleashed unchecked creativity. 22 00:01:04,865 --> 00:01:07,301 Now, their secrets are revealed 23 00:01:07,435 --> 00:01:09,670 as we discover the amazing stories 24 00:01:09,770 --> 00:01:11,504 of their construction. 25 00:01:12,372 --> 00:01:13,607 [Mat] Look at this building, 26 00:01:13,741 --> 00:01:15,743 and your brain just screams at you. 27 00:01:15,843 --> 00:01:17,678 This building does not make sense. 28 00:01:17,778 --> 00:01:20,948 [dramatic choral music] 29 00:01:21,048 --> 00:01:23,116 [Jay] To try and understand... 30 00:01:24,451 --> 00:01:26,987 How did they build that? 31 00:01:28,923 --> 00:01:31,592 If I were to show you a 16-story glass-clad tower 32 00:01:31,725 --> 00:01:34,861 that has a huge canyon carved right through its center, 33 00:01:35,261 --> 00:01:38,031 you'd probably think the folks who designed it were mad, 34 00:01:38,265 --> 00:01:39,400 and you'd be right. 35 00:01:39,500 --> 00:01:41,802 This awesome project in Denver, Colorado, 36 00:01:41,935 --> 00:01:44,338 is the design of Chinese studio MAD Architects. 37 00:01:44,738 --> 00:01:47,040 Seriously, how did they build that? 38 00:01:47,140 --> 00:01:49,276 [dramatic music] 39 00:01:49,376 --> 00:01:52,012 [Jay] The American West's rugged mountains and canyons 40 00:01:52,112 --> 00:01:53,413 have provided inspiration for 41 00:01:53,513 --> 00:01:56,016 authors, filmmakers, and artists. 42 00:01:57,518 --> 00:02:00,421 So, it may be no surprise that in 2019, 43 00:02:00,521 --> 00:02:03,056 they inspired a developer and an architect 44 00:02:03,156 --> 00:02:05,592 to have an incredible dream. 45 00:02:05,692 --> 00:02:08,495 [dramatic music] 46 00:02:09,363 --> 00:02:12,032 [Jay] They decided to build a towering apartment building 47 00:02:12,165 --> 00:02:15,202 in Denver, Colorado that captured the wilderness 48 00:02:15,302 --> 00:02:18,004 in a way never seen before. 49 00:02:18,338 --> 00:02:20,941 It's a piece of amazing theater. 50 00:02:21,041 --> 00:02:23,443 [awe-inspiring music] 51 00:02:23,544 --> 00:02:26,346 The building itself redefines the city. 52 00:02:27,214 --> 00:02:29,316 [Jay] A structure cracked open, 53 00:02:29,983 --> 00:02:32,819 a mountain chasm carved into its side. 54 00:02:33,487 --> 00:02:36,357 The canyon really took elements of the building 55 00:02:36,457 --> 00:02:38,191 and pulled them apart. 56 00:02:38,291 --> 00:02:39,860 [Jay] It was an incredible design 57 00:02:39,993 --> 00:02:42,029 with incredible challenges. 58 00:02:42,796 --> 00:02:46,666 There were moments where it was complete despair. 59 00:02:46,800 --> 00:02:48,435 I did not think it was going to work, 60 00:02:48,535 --> 00:02:51,004 and I did not think that we would be able to pull it off. 61 00:02:51,138 --> 00:02:52,939 [awe-inspiring music] 62 00:02:53,040 --> 00:02:57,010 [Jay] 187 apartments over 16 floors, 63 00:02:57,143 --> 00:02:58,979 with a breath-taking façade. 64 00:03:00,080 --> 00:03:02,416 High-rise living that allows you to walk 65 00:03:02,516 --> 00:03:04,851 straight out into a ravine. 66 00:03:05,318 --> 00:03:07,954 This is One River North. 67 00:03:09,055 --> 00:03:10,423 So... 68 00:03:10,557 --> 00:03:11,958 How'd they build it? 69 00:03:13,994 --> 00:03:15,863 [intriguing music] 70 00:03:15,963 --> 00:03:17,898 [Jay] Denver is set on the high plains 71 00:03:17,998 --> 00:03:21,601 and nestled at the foot of the Rocky Mountains. 72 00:03:22,469 --> 00:03:24,138 [intriguing music] 73 00:03:24,238 --> 00:03:25,572 [Jay] It's a city surrounded by 74 00:03:25,706 --> 00:03:28,042 some of the most spectacular scenery 75 00:03:28,142 --> 00:03:29,376 in the country. 76 00:03:29,877 --> 00:03:32,513 People move here to take advantage of getting out into 77 00:03:32,613 --> 00:03:34,682 its incredible natural surroundings, 78 00:03:34,782 --> 00:03:37,150 hiking, biking, and horse-back riding 79 00:03:37,250 --> 00:03:39,052 on its beautiful trails. 80 00:03:39,152 --> 00:03:42,222 [intriguing music] 81 00:03:42,322 --> 00:03:44,558 [Jay] But, as with many American cities, 82 00:03:44,658 --> 00:03:47,361 Denver is locked in an ongoing battle 83 00:03:47,461 --> 00:03:49,263 with traffic congestion. 84 00:03:50,097 --> 00:03:53,099 Getting out to the mountains isn't always easy. 85 00:03:54,101 --> 00:03:57,204 Developer Kevin Ratner wants to change that. 86 00:03:57,704 --> 00:04:00,273 [Kevin] I think that people are happier in nature. 87 00:04:01,876 --> 00:04:05,979 And I also think that people respond to, uh, 88 00:04:06,079 --> 00:04:10,016 the natural environment in a way that is, uh... 89 00:04:10,584 --> 00:04:11,852 That feels better. 90 00:04:11,952 --> 00:04:13,820 [intriguing music] 91 00:04:13,920 --> 00:04:16,557 [Jay] So, when he snaps up a piece of prime real estate 92 00:04:16,623 --> 00:04:18,458 in the River North district of Denver, 93 00:04:19,025 --> 00:04:22,296 Kevin brings in global architecture firm MAD. 94 00:04:23,063 --> 00:04:25,766 Although they have a history of creating designs 95 00:04:25,866 --> 00:04:27,268 inspired by nature, 96 00:04:27,368 --> 00:04:29,870 such as Suzhou Stadium in China, 97 00:04:29,970 --> 00:04:33,974 this time, they wanna take things much further. 98 00:04:34,475 --> 00:04:35,909 What we really wanted to do is, 99 00:04:36,009 --> 00:04:37,811 we wanted to collapse that distance between 100 00:04:37,912 --> 00:04:38,979 the Rocky Mountains, 101 00:04:39,113 --> 00:04:40,814 and bring the trails, bring the water 102 00:04:40,915 --> 00:04:42,182 to the residence. 103 00:04:43,350 --> 00:04:47,487 I was thinking, "How about you live in the building, 104 00:04:47,587 --> 00:04:52,426 "but you feel yourself living in the natural landscape? 105 00:04:52,526 --> 00:04:54,327 Like a canyon space." 106 00:04:55,595 --> 00:04:59,066 We cut through the structure in different levels. 107 00:04:59,967 --> 00:05:03,971 So, it, it become not only a, a natural garden, 108 00:05:04,338 --> 00:05:08,408 but it's become, uh, a walkable experience. 109 00:05:08,976 --> 00:05:12,779 [intriguing music] 110 00:05:12,880 --> 00:05:14,682 [Jay] To achieve this daring vision, 111 00:05:14,782 --> 00:05:16,983 starting from pile foundations, 112 00:05:17,084 --> 00:05:20,087 a central core will rise up 216 feet 113 00:05:20,187 --> 00:05:23,857 to create 187 apartments across 16 floors. 114 00:05:23,957 --> 00:05:26,660 [intriguing music] 115 00:05:26,760 --> 00:05:29,262 [Jay] It will be wrapped in a beautiful curtain wall, 116 00:05:29,362 --> 00:05:32,732 made up of thousands of individual pieces of glass. 117 00:05:33,701 --> 00:05:36,537 But then, a section will be ripped away 118 00:05:36,670 --> 00:05:38,939 to reveal a fantasy canyon. 119 00:05:39,639 --> 00:05:42,475 Making it a reality will mean finding ways to support floors 120 00:05:42,576 --> 00:05:44,878 that appear to hang in open space. 121 00:05:45,913 --> 00:05:47,714 And figuring out how to sculpt a ravine 122 00:05:47,814 --> 00:05:50,017 in the heart of a 21st-century apartment building. 123 00:05:50,117 --> 00:05:53,187 [intriguing music] 124 00:05:53,287 --> 00:05:54,388 [Jay] It's a bold idea, 125 00:05:54,522 --> 00:05:57,191 and a big gamble for the developers. 126 00:05:57,324 --> 00:06:01,194 [intriguing music] 127 00:06:01,662 --> 00:06:03,431 I thought for sure that there's no way 128 00:06:03,531 --> 00:06:04,864 that they would go for it. 129 00:06:04,931 --> 00:06:07,467 But instead, they, it, they were like, "How," you know, 130 00:06:07,567 --> 00:06:09,402 "how can we not build this project?" 131 00:06:09,536 --> 00:06:10,670 Right? 132 00:06:10,770 --> 00:06:12,940 [exciting music] 133 00:06:13,040 --> 00:06:14,408 [Jay] With the developer committed, 134 00:06:14,809 --> 00:06:17,344 they break ground in summer, 2021. 135 00:06:18,946 --> 00:06:21,581 They dig out 40-foot-deep piles 136 00:06:23,050 --> 00:06:26,686 before beginning to construct the 16-story building. 137 00:06:29,156 --> 00:06:30,891 In a typical apartment building, 138 00:06:30,991 --> 00:06:34,160 you just build a floor and move up to the next. 139 00:06:35,228 --> 00:06:38,298 This one is anything but typical. 140 00:06:39,433 --> 00:06:41,535 When you literally cut into a building, 141 00:06:41,601 --> 00:06:43,671 you're creating massive problems. 142 00:06:44,672 --> 00:06:48,742 To create this organic space was quite a challenge, 143 00:06:48,876 --> 00:06:52,446 because that's, that shape is really irregular 144 00:06:52,546 --> 00:06:54,948 and it goes through all different levels. 145 00:06:56,083 --> 00:06:57,918 [Ed] Each floor was unique. 146 00:06:58,018 --> 00:07:03,456 Each floor had its own geometry, its own design loads and shape. 147 00:07:03,523 --> 00:07:06,360 And so, there was different design at each level. 148 00:07:06,460 --> 00:07:10,197 [serious music] 149 00:07:10,330 --> 00:07:11,698 [Jay] Most often, 150 00:07:11,798 --> 00:07:14,601 floors are supported by regularly placed columns. 151 00:07:15,068 --> 00:07:17,838 But the canyon design makes that impossible. 152 00:07:18,439 --> 00:07:23,477 [Jon] The issue was trying to reduce the number of columns 153 00:07:23,577 --> 00:07:24,878 that came down in the canyon. 154 00:07:25,011 --> 00:07:28,181 'Cause we were really keen on creating a space 155 00:07:28,281 --> 00:07:30,150 where it was immersive. 156 00:07:30,517 --> 00:07:33,020 We really wanted them to feel like they were in nature, 157 00:07:33,353 --> 00:07:35,555 where you didn't feel like you were in 158 00:07:35,689 --> 00:07:36,890 an architectural environment. 159 00:07:36,990 --> 00:07:39,493 And so, that was really the struggle that, uh, 160 00:07:39,593 --> 00:07:41,529 the structural engineer had to deal with. 161 00:07:42,363 --> 00:07:45,032 [Jay] In order to avoid using columns in the canyon, 162 00:07:45,165 --> 00:07:50,003 the engineers turned to a tried and tested engineering trick. 163 00:07:50,837 --> 00:07:53,173 [Ed] The concept, from the beginning 164 00:07:53,273 --> 00:07:54,875 and all the way through, 165 00:07:54,975 --> 00:07:57,277 involved cantilevering that front face. 166 00:07:57,377 --> 00:08:00,381 A cantilever is an overhang that transfers all this weight 167 00:08:00,481 --> 00:08:03,250 into the fixed end down into the foundations. 168 00:08:03,350 --> 00:08:06,419 This allows the floor to project into space. 169 00:08:07,053 --> 00:08:09,757 [Jay] Although the cantilevers allow them to create the canyon, 170 00:08:09,890 --> 00:08:12,059 they now have to deal with the additional forces 171 00:08:12,159 --> 00:08:14,094 they put on the rest of the building. 172 00:08:14,194 --> 00:08:16,630 [serious music] 173 00:08:16,730 --> 00:08:19,567 The stresses get very high around the supports, 174 00:08:19,667 --> 00:08:21,468 and the punching shear stresses 175 00:08:21,601 --> 00:08:24,771 transferring all that heavy load through columns 176 00:08:24,871 --> 00:08:27,074 are a challenge to deal with. 177 00:08:27,842 --> 00:08:30,410 [Jay] These additional loads are creating punching shear, 178 00:08:31,144 --> 00:08:33,714 threatening the stability of the rest of the building. 179 00:08:34,281 --> 00:08:37,284 Punching shear can lead to a building's collapse. 180 00:08:38,386 --> 00:08:41,555 Imagine a slab is a piece of paper, 181 00:08:41,655 --> 00:08:43,957 and a pen is the column. 182 00:08:44,458 --> 00:08:47,728 Put the paper above the pen, push down, 183 00:08:47,828 --> 00:08:49,596 and the pen punctures it. 184 00:08:50,163 --> 00:08:52,566 That's what can happen with a column and a slab. 185 00:08:52,666 --> 00:08:56,403 [dramatic music] 186 00:08:56,536 --> 00:08:59,006 [Jay] How would they prevent this apartment building 187 00:08:59,106 --> 00:09:01,775 from collapsing in on itself? 188 00:09:04,811 --> 00:09:07,081 [intriguing music] 189 00:09:07,181 --> 00:09:08,516 [Jay] In Denver, Colorado, 190 00:09:08,616 --> 00:09:10,017 engineers are battling to create 191 00:09:10,117 --> 00:09:12,419 an extraordinary new apartment building 192 00:09:12,519 --> 00:09:15,322 ripped open by a man-made canyon. 193 00:09:16,323 --> 00:09:19,026 The complex design creates immense forces 194 00:09:19,126 --> 00:09:21,294 where the columns meet the floor slabs, 195 00:09:21,395 --> 00:09:24,698 which could prove to be too much for the structure to bear. 196 00:09:25,433 --> 00:09:28,001 They turn to an ingenious solution. 197 00:09:28,969 --> 00:09:30,937 [Ed] We reinforce all around the column 198 00:09:31,038 --> 00:09:32,606 with something called stud rails, 199 00:09:32,939 --> 00:09:37,678 which is bars that are cast into the slab 200 00:09:37,778 --> 00:09:40,013 that provide the shear reinforcing 201 00:09:40,113 --> 00:09:41,348 around the column. 202 00:09:42,382 --> 00:09:43,984 [Jay] They do this by spreading the pressure 203 00:09:44,084 --> 00:09:46,187 over a wide area of the column. 204 00:09:46,287 --> 00:09:48,889 [serious music] 205 00:09:49,022 --> 00:09:53,260 [Jay] Now the curvy concrete floor slabs can be poured. 206 00:09:54,261 --> 00:09:56,529 Usually a fairly straightforward process, 207 00:09:56,663 --> 00:10:00,233 but not when some of your floors have nothing underneath them 208 00:10:00,334 --> 00:10:01,868 for over 100 feet. 209 00:10:02,502 --> 00:10:04,137 [Ed] Floors do not stack. 210 00:10:04,238 --> 00:10:08,609 There is no structure below to shore off of for construction. 211 00:10:08,709 --> 00:10:10,911 Shoring is when you use temporary props 212 00:10:11,011 --> 00:10:13,213 to support each concrete floor 213 00:10:13,313 --> 00:10:15,816 so that it can be poured and, and held in place 214 00:10:15,883 --> 00:10:17,384 until it dries. 215 00:10:18,486 --> 00:10:21,222 [Ryan] In a typical concrete frame building, 216 00:10:21,355 --> 00:10:23,891 the formwork and reshoring system 217 00:10:24,024 --> 00:10:27,962 is installed across approximately four floors. 218 00:10:28,329 --> 00:10:29,696 In this building, 219 00:10:30,530 --> 00:10:35,769 there were instances in which it was across 9 or 11 floors. 220 00:10:36,603 --> 00:10:40,174 So, two to three times the amount of floors 221 00:10:40,674 --> 00:10:44,411 had reshoring on them during the construction process. 222 00:10:45,946 --> 00:10:50,417 [Jay] At last, by August 2022, the concrete slabs are dry. 223 00:10:52,686 --> 00:10:55,055 Next, it's time to enclose the building 224 00:10:55,155 --> 00:10:58,025 by installing a curtain wall, which will be made up of 225 00:10:58,158 --> 00:11:00,827 over 2700 individual pieces of glass. 226 00:11:00,927 --> 00:11:03,430 [intriguing music] 227 00:11:03,531 --> 00:11:05,432 [Jay] Complicated enough on its own, 228 00:11:05,532 --> 00:11:09,269 the canyon slicing through it creates an enormous headache. 229 00:11:10,370 --> 00:11:15,342 The high quantity of widely-varying shapes and sizes 230 00:11:15,442 --> 00:11:17,177 of the enclosure system 231 00:11:17,611 --> 00:11:21,915 creates a, a challenge for coordination. 232 00:11:23,017 --> 00:11:25,419 [Jay] It's a huge jigsaw puzzle for the team. 233 00:11:25,920 --> 00:11:28,756 Each piece has to be carefully numbered. 234 00:11:29,256 --> 00:11:32,125 Then it takes ten months of precision work 235 00:11:32,793 --> 00:11:35,596 to complete the glass installation. 236 00:11:35,696 --> 00:11:41,468 [serious music] 237 00:11:41,602 --> 00:11:43,504 [Jay] The final challenge is creating 238 00:11:43,604 --> 00:11:46,072 the sculptural surface of the canyon. 239 00:11:46,807 --> 00:11:48,109 How can you recreate 240 00:11:48,209 --> 00:11:50,944 what's taken hundreds of thousands of years 241 00:11:51,078 --> 00:11:53,347 for nature to form? 242 00:11:53,781 --> 00:11:57,351 The canyon itself was a first of its kind for us. 243 00:11:57,751 --> 00:12:02,689 We had never, uh, seen it, much less built it. 244 00:12:04,458 --> 00:12:05,960 [Jay] To make the canyon a reality, 245 00:12:06,060 --> 00:12:08,595 they find inspiration from a surprising source. 246 00:12:10,130 --> 00:12:12,232 [people screaming excitedly] 247 00:12:14,101 --> 00:12:17,037 The same kind of technology that they use to create theme parks 248 00:12:17,137 --> 00:12:19,139 is used to create features here. 249 00:12:19,806 --> 00:12:22,476 [Jay] The system they use is known as chip. 250 00:12:23,276 --> 00:12:26,847 Steel rods are meticulously bet and covered in mesh, 251 00:12:26,980 --> 00:12:28,649 molded to create the canyon. 252 00:12:28,982 --> 00:12:33,287 The backbone of it was prefabricated 253 00:12:33,387 --> 00:12:36,523 and shipped to site in pieces. 254 00:12:37,824 --> 00:12:40,727 [Jay] Once in place, it's coated in plaster. 255 00:12:41,695 --> 00:12:43,497 In total, ten stories of the building 256 00:12:43,631 --> 00:12:45,899 are covered in these plaster sculptures, 257 00:12:45,999 --> 00:12:48,001 slowly forming the canyon. 258 00:12:49,269 --> 00:12:52,473 [Ed] I don't think we felt like it was really coming together 259 00:12:52,606 --> 00:12:54,508 until the plaster and the finishes, 260 00:12:54,608 --> 00:12:56,343 and then, and then it just was... 261 00:12:56,443 --> 00:12:59,213 It just became a really cool reality. 262 00:12:59,313 --> 00:13:03,750 [empowering music] 263 00:13:04,184 --> 00:13:07,921 [Jay] In May 2024, after nearly three years of work, 264 00:13:09,156 --> 00:13:12,926 One River North is ready to welcome its first residents. 265 00:13:13,894 --> 00:13:16,197 Their new homes completely revolutionize 266 00:13:16,297 --> 00:13:17,998 what city living can look like. 267 00:13:18,398 --> 00:13:20,867 The building exceeded my expectations. 268 00:13:22,569 --> 00:13:24,238 When you stand on the seventh floor, 269 00:13:24,371 --> 00:13:26,406 you can look up, and you can see all the way up 270 00:13:26,540 --> 00:13:27,708 through the canyon, 271 00:13:27,842 --> 00:13:29,376 all the way up to the top of the building. 272 00:13:29,476 --> 00:13:32,146 And the first time I walked out there and experienced that, 273 00:13:32,646 --> 00:13:34,581 I was just, I was really just blown away. 274 00:13:35,682 --> 00:13:38,152 [Dr. Mabry] Who wouldn't wanna live close to nature like this? 275 00:13:38,552 --> 00:13:40,387 You don't have to drive for an hour 276 00:13:40,487 --> 00:13:42,389 or take a walk outside of the city. 277 00:13:42,522 --> 00:13:46,093 You've got a canyon walk right outside your front door. 278 00:13:46,193 --> 00:13:48,361 [empowering music] 279 00:13:48,462 --> 00:13:50,164 [Jay] An innovative living landmark 280 00:13:50,264 --> 00:13:52,499 that brings nature and the mountains 281 00:13:52,966 --> 00:13:54,468 to people's doorsteps. 282 00:13:54,935 --> 00:13:56,069 [Monica] It's gorgeous. 283 00:13:56,169 --> 00:13:59,073 It has water flow, it has live trees. 284 00:13:59,173 --> 00:14:00,874 I mean, I don't think there's another building 285 00:14:00,974 --> 00:14:03,277 not only in Denver, but in the US that, 286 00:14:03,410 --> 00:14:04,611 that has that. 287 00:14:04,945 --> 00:14:08,148 [Ryan] I remember driving down the highway 288 00:14:08,248 --> 00:14:12,152 and catching the building out of the corner of my eye, 289 00:14:12,419 --> 00:14:14,788 and it just, it just struck me in, 290 00:14:14,888 --> 00:14:16,156 in a great way, 291 00:14:16,256 --> 00:14:19,326 how significant that canyon was, 292 00:14:19,660 --> 00:14:21,295 and how visible it was gonna be 293 00:14:21,428 --> 00:14:24,632 from so many different points of the city. 294 00:14:24,765 --> 00:14:28,335 [empowering music] 295 00:14:30,704 --> 00:14:36,643 [upbeat percussion music] 296 00:14:39,479 --> 00:14:40,948 Two years before the United States 297 00:14:41,081 --> 00:14:42,482 sent astronauts to the moon, 298 00:14:42,616 --> 00:14:44,985 the city of Saint Louis was sending intrepid sightseers 299 00:14:45,119 --> 00:14:47,187 to the top of the world's largest arch. 300 00:14:47,287 --> 00:14:49,623 But before anyone went upward bound, 301 00:14:49,756 --> 00:14:51,491 a problem had to be solved. 302 00:14:51,591 --> 00:14:52,826 Because of its enormous size, 303 00:14:52,959 --> 00:14:55,829 the arch had to be made in two separate sections. 304 00:14:55,929 --> 00:14:57,831 Its designers would only know for sure 305 00:14:57,931 --> 00:14:59,266 if they got their math right 306 00:14:59,366 --> 00:15:01,268 and if the two sections would actually meet in the middle 307 00:15:01,368 --> 00:15:05,338 when they were raised 630 feet up in the sky. 308 00:15:07,808 --> 00:15:09,343 [intriguing] music] 309 00:15:09,443 --> 00:15:10,878 [Jay] In 1947, 310 00:15:10,978 --> 00:15:12,946 the state of Missouri challenged the architecture world 311 00:15:13,046 --> 00:15:16,316 to design a monument that would honor the spirit 312 00:15:16,416 --> 00:15:18,085 of the western pioneers. 313 00:15:18,185 --> 00:15:20,855 [intriguing music] 314 00:15:20,955 --> 00:15:24,458 [dynamic music] 315 00:15:24,925 --> 00:15:26,527 [Jay] When completed, 316 00:15:27,361 --> 00:15:30,630 it would become one of the most recognizable structures 317 00:15:30,730 --> 00:15:32,132 in the United States. 318 00:15:33,500 --> 00:15:35,569 It's an iconic construction. 319 00:15:35,669 --> 00:15:38,038 It completely changes the skyline. 320 00:15:38,706 --> 00:15:41,141 [Jay] New technology would have to be developed 321 00:15:41,241 --> 00:15:42,610 in order to build it. 322 00:15:42,710 --> 00:15:44,344 [Pam] How do you even build this 323 00:15:44,444 --> 00:15:49,483 when there's no crane that can go 630 feet in the air? 324 00:15:49,549 --> 00:15:51,552 [Jay] But controversial hiring practices 325 00:15:51,685 --> 00:15:54,688 also lead to protests during its construction. 326 00:15:55,522 --> 00:15:57,691 They climbed the arch and handcuffed themselves 327 00:15:57,791 --> 00:15:58,859 to the structure. 328 00:15:58,993 --> 00:16:00,894 [dynamic music] 329 00:16:00,994 --> 00:16:02,562 [Jay] Twenty-eight years later, 330 00:16:02,663 --> 00:16:05,298 it would soar from foundations piled 60 feet underground, 331 00:16:06,466 --> 00:16:08,435 630 feet into the air 332 00:16:08,569 --> 00:16:11,404 to become the tallest monument in the United States... 333 00:16:11,504 --> 00:16:13,440 [dramatic music] 334 00:16:13,573 --> 00:16:16,243 [Jay] ...and the highest arch in the world. 335 00:16:17,044 --> 00:16:19,779 This is the Gateway Arch. 336 00:16:20,414 --> 00:16:22,750 So, how did they build it? 337 00:16:22,850 --> 00:16:25,619 [serious music] 338 00:16:28,755 --> 00:16:30,324 [Jay] Saint Louis, which is almost 339 00:16:30,424 --> 00:16:32,726 the geographical center of the US, 340 00:16:33,427 --> 00:16:35,762 was originally a humble fur-trading post. 341 00:16:37,431 --> 00:16:39,633 And in 1804, its position made it 342 00:16:39,733 --> 00:16:42,436 the perfect jumping-off point for two pioneers, 343 00:16:42,536 --> 00:16:43,904 Lewis and Clark, 344 00:16:44,004 --> 00:16:46,907 as they set out to explore the uncharted West. 345 00:16:47,007 --> 00:16:49,142 [awe-inspiring music] 346 00:16:49,242 --> 00:16:52,445 [Jay] Over the next 100 years, the city grew fast, 347 00:16:53,814 --> 00:16:55,916 with the Mississippi and Missouri rivers 348 00:16:56,016 --> 00:16:58,451 making it the perfect trading route. 349 00:16:59,520 --> 00:17:02,556 But by the early 20th century, 350 00:17:02,690 --> 00:17:04,325 with trading moving to the railroad 351 00:17:04,425 --> 00:17:06,393 and the Great Depression taking its toll, 352 00:17:06,527 --> 00:17:08,795 the city was down on its luck. 353 00:17:09,129 --> 00:17:10,664 [Pam] Saint Louis, at the time, 354 00:17:11,231 --> 00:17:14,901 was facing, like much of the country, a depression. 355 00:17:15,001 --> 00:17:16,703 A lot of people out of work. 356 00:17:16,803 --> 00:17:20,874 The riverfront itself had become a lot of abandoned warehouses 357 00:17:20,974 --> 00:17:23,577 that were falling into disrepair. 358 00:17:24,979 --> 00:17:27,748 [Jay] Saint Louis needed to do something 359 00:17:27,848 --> 00:17:29,450 to turn its fortunes around. 360 00:17:30,250 --> 00:17:33,320 In 1947, they launched an enormous competition 361 00:17:33,420 --> 00:17:35,355 to design an incredible monument 362 00:17:35,455 --> 00:17:38,225 that will celebrate the city's pioneering history 363 00:17:38,893 --> 00:17:41,628 and give it back its sense of pride. 364 00:17:42,496 --> 00:17:44,398 They wanted something that would spark excitement 365 00:17:44,531 --> 00:17:45,899 and interest in the populace, 366 00:17:45,999 --> 00:17:48,869 and become known nationally as well as internationally. 367 00:17:50,003 --> 00:17:53,707 [Jay] There are 172 entrants from across the country. 368 00:17:54,374 --> 00:17:56,710 The winner is Eero Saarinen. 369 00:17:57,811 --> 00:18:01,248 He would go on to create the futuristic TWA Flight Center 370 00:18:01,348 --> 00:18:03,116 in New York's JFK Airport 371 00:18:03,250 --> 00:18:07,120 and the Dulles National Airport outside Washington D.C. 372 00:18:08,455 --> 00:18:13,360 But winning the competition is his first major commission. 373 00:18:13,760 --> 00:18:15,562 Eero Saarinen envisioned something that 374 00:18:15,662 --> 00:18:16,897 represented Saint Louis 375 00:18:16,997 --> 00:18:19,600 as the gateway to the West in a very literal sense. 376 00:18:19,733 --> 00:18:21,068 When you look at the arch, 377 00:18:21,168 --> 00:18:22,769 you can imagine it as a doorway 378 00:18:22,869 --> 00:18:25,171 to these new and unexplored lands. 379 00:18:25,272 --> 00:18:27,440 It really shows the pioneer spirit. 380 00:18:28,709 --> 00:18:29,943 [Jay] His vision is for 381 00:18:30,076 --> 00:18:32,913 a futuristic reimagining of an ancient structure. 382 00:18:33,179 --> 00:18:35,282 An arch built on a scale so vast, 383 00:18:35,416 --> 00:18:37,618 it will pose unprecedented challenges 384 00:18:37,752 --> 00:18:39,586 for the engineers. 385 00:18:40,855 --> 00:18:43,557 First, they will need to create foundations strong enough 386 00:18:43,657 --> 00:18:47,160 to support the weight of the 630-foot-tall arch. 387 00:18:47,995 --> 00:18:49,529 Then, they'll need to figure out 388 00:18:49,630 --> 00:18:51,599 how to build its two towering legs 389 00:18:51,732 --> 00:18:54,034 from individual sections. 390 00:18:54,901 --> 00:18:57,838 The whole plan will rest on careful calculations, 391 00:18:57,938 --> 00:19:00,574 which will only be proved right or wrong 392 00:19:00,674 --> 00:19:04,578 when the two halves of the arch meet in the middle. 393 00:19:05,546 --> 00:19:07,013 If they pull it off, 394 00:19:07,147 --> 00:19:09,483 visitors will be able to take a specially-built tram 395 00:19:09,616 --> 00:19:12,586 up to an observation deck at the top, 396 00:19:12,686 --> 00:19:15,256 creating a magnificent gateway tribute 397 00:19:15,356 --> 00:19:17,825 to the westward expansion of the United States 398 00:19:17,925 --> 00:19:20,327 and its historic pioneers. 399 00:19:22,563 --> 00:19:25,098 The commission is won in 1948. 400 00:19:26,033 --> 00:19:29,136 But it takes another 14 years to pull together the funding 401 00:19:29,236 --> 00:19:30,470 to start work. 402 00:19:32,072 --> 00:19:35,009 On the upside, this gives Saarinen and the team 403 00:19:35,109 --> 00:19:38,278 time to work out how on earth they're gonna build it 404 00:19:38,378 --> 00:19:41,214 in a time before computer-aided design. 405 00:19:42,849 --> 00:19:44,484 Saarinen has to calculate 406 00:19:44,618 --> 00:19:46,320 the total weight of the structure, 407 00:19:46,420 --> 00:19:50,257 the dimensions, the angles, the curves, 408 00:19:50,624 --> 00:19:52,259 the strength of materials... 409 00:19:52,760 --> 00:19:54,194 On and on and on. 410 00:19:54,327 --> 00:19:55,695 It seems almost impossible to us today 411 00:19:55,829 --> 00:19:58,698 that they did this without the benefit of modern computers. 412 00:19:59,600 --> 00:20:01,034 [Jay] At the heart of Saarinen's plan 413 00:20:01,168 --> 00:20:03,237 is a piece of engineering magic. 414 00:20:03,771 --> 00:20:06,806 It's called an inverted catenary curve. 415 00:20:07,173 --> 00:20:10,010 A catenary curve is the shape of a hanging chain 416 00:20:10,144 --> 00:20:11,512 that forms naturally 417 00:20:11,612 --> 00:20:15,415 as a result of gravity pressing along the entire chain. 418 00:20:16,316 --> 00:20:18,919 [Susan] I went down in, into the basement, 419 00:20:19,253 --> 00:20:24,658 and up on the ceiling, um, 420 00:20:24,758 --> 00:20:27,828 were these chains that were hanging. 421 00:20:28,295 --> 00:20:31,432 He was studying the proportions 422 00:20:31,732 --> 00:20:37,404 and what the exact curve ratio should be. 423 00:20:38,105 --> 00:20:39,740 [Jay] Because the forces are distributed 424 00:20:39,840 --> 00:20:41,275 evenly and efficiently, 425 00:20:41,642 --> 00:20:44,078 when one of these hanging curves is inverted, 426 00:20:44,178 --> 00:20:46,313 it becomes incredibly strong. 427 00:20:47,280 --> 00:20:49,083 Just as well when you're building 428 00:20:49,183 --> 00:20:50,584 the nation's tallest monument. 429 00:20:53,120 --> 00:20:54,989 [serious music] 430 00:20:55,089 --> 00:20:57,158 [Jay] In June 1962, 431 00:20:57,258 --> 00:20:59,226 work begins clearing the site. 432 00:21:00,194 --> 00:21:03,129 First, they need to create the foundations. 433 00:21:05,566 --> 00:21:07,368 These footings need to be strong enough 434 00:21:07,468 --> 00:21:09,070 to handle the downward forces 435 00:21:09,170 --> 00:21:12,138 that will be created by the 630-foot arch. 436 00:21:13,140 --> 00:21:15,776 This means using reinforced concrete; 437 00:21:16,177 --> 00:21:18,912 26,000 tons of it. 438 00:21:20,547 --> 00:21:22,082 To make the concrete strong, 439 00:21:22,182 --> 00:21:24,184 they'll need to pour it continuously. 440 00:21:24,751 --> 00:21:27,754 Otherwise, it won't set uniformly. 441 00:21:29,823 --> 00:21:31,792 Truck after truck had to come in, 442 00:21:31,892 --> 00:21:35,695 so it almost had to be like a, a finely-tuned concert 443 00:21:35,796 --> 00:21:39,366 to make sure they got in, dumped their load of concrete, 444 00:21:39,466 --> 00:21:42,736 and moved off so that the next one could come in. 445 00:21:43,303 --> 00:21:44,938 [Jay] Twenty-six hours 446 00:21:45,038 --> 00:21:48,441 and 2,000 trucks of concrete later, 447 00:21:49,910 --> 00:21:52,078 the foundations are poured. 448 00:21:53,947 --> 00:21:55,349 The next major challenge 449 00:21:55,449 --> 00:21:57,617 is making sure the legs are gonna be strong enough 450 00:21:57,751 --> 00:21:59,452 to withstand the arch's weight. 451 00:22:00,287 --> 00:22:04,091 For the solution, the team turns to the humble triangle. 452 00:22:04,825 --> 00:22:06,660 Each section of the arch is created from 453 00:22:06,760 --> 00:22:10,063 three super-strong links of steel welded together. 454 00:22:11,131 --> 00:22:13,667 Equilateral triangles are the strongest shape, 455 00:22:13,767 --> 00:22:16,770 as they distribute forces equally and evenly 456 00:22:16,870 --> 00:22:18,171 across all three sides. 457 00:22:18,271 --> 00:22:20,107 No matter where the force comes from, 458 00:22:20,541 --> 00:22:23,310 you know the structure will not deform. 459 00:22:23,977 --> 00:22:25,479 [Jay] As each piece is completed, 460 00:22:25,579 --> 00:22:30,617 they are welded inside and out, the legs slowly climbing higher. 461 00:22:30,918 --> 00:22:34,021 [serious music] 462 00:22:34,154 --> 00:22:36,157 [calm music] 463 00:22:36,257 --> 00:22:37,491 [Jay] As work progresses, 464 00:22:37,591 --> 00:22:39,693 in July 1964, 465 00:22:39,827 --> 00:22:41,629 the same year the Civil Rights Act 466 00:22:41,729 --> 00:22:43,030 is signed into law, 467 00:22:43,764 --> 00:22:46,867 the arch becomes the focus of not the city's rebirth, 468 00:22:46,967 --> 00:22:50,370 but of racial injustice and discrimination. 469 00:22:51,639 --> 00:22:54,141 Local man Percy Green scales it 470 00:22:54,241 --> 00:22:56,510 to protest about how few African Americans 471 00:22:56,610 --> 00:22:58,478 are working on the project. 472 00:22:59,145 --> 00:23:03,917 His six-hour sit-in is reported across the country. 473 00:23:04,918 --> 00:23:06,887 [Jennifer] This protest actually brought attention 474 00:23:06,987 --> 00:23:08,556 to these unfair hiring practices, 475 00:23:08,656 --> 00:23:10,524 and made a change in federal hiring 476 00:23:10,624 --> 00:23:12,659 with repercussions that echoes today. 477 00:23:13,026 --> 00:23:14,194 [Jay] Although the protest 478 00:23:14,295 --> 00:23:15,896 doesn't improve things immediately, 479 00:23:16,496 --> 00:23:18,899 it helps bring about long-term change. 480 00:23:19,033 --> 00:23:23,904 [serious music] 481 00:23:24,004 --> 00:23:28,108 [Jay] On site, work continues, though it soon hits a problem. 482 00:23:28,375 --> 00:23:29,877 The arch will be so high, 483 00:23:29,977 --> 00:23:31,645 that there isn't a crane tall enough 484 00:23:31,745 --> 00:23:32,913 to finish the building it. 485 00:23:33,313 --> 00:23:34,581 [Jennifer] For the first few sections, 486 00:23:34,681 --> 00:23:35,949 they used regular cranes. 487 00:23:36,082 --> 00:23:38,552 At about 72 feet, they had to switch their plan, 488 00:23:38,652 --> 00:23:40,921 because the crane couldn't reach that high. 489 00:23:42,756 --> 00:23:46,527 [Jay] The solution is to devise something truly extraordinary. 490 00:23:47,494 --> 00:23:50,598 A crane that can climb the arch as its built, 491 00:23:51,065 --> 00:23:53,567 pulled up by rails attached to each leg. 492 00:23:54,001 --> 00:23:55,469 [Barb] They were able to have a crane 493 00:23:55,569 --> 00:23:58,105 actually climb up that rail. 494 00:23:58,205 --> 00:23:59,506 The cranes would be able to 495 00:23:59,606 --> 00:24:02,676 attach steel sections on each leg. 496 00:24:03,977 --> 00:24:06,513 [Jay] It's not long, though, before the team is facing 497 00:24:06,647 --> 00:24:07,948 its next challenge. 498 00:24:08,048 --> 00:24:10,284 The higher up they went, the stronger the winds felt. 499 00:24:10,384 --> 00:24:12,319 There could be gusts of wind that reached 500 00:24:12,453 --> 00:24:14,154 50 or more miles per hour. 501 00:24:14,621 --> 00:24:16,757 [Hayley] Winds create sideways pressure 502 00:24:16,824 --> 00:24:17,991 on a building. 503 00:24:18,125 --> 00:24:20,661 So, you have to factor in additional strength. 504 00:24:20,994 --> 00:24:22,796 But if you make it too rigid, 505 00:24:22,897 --> 00:24:26,500 then the force from the winds could cause structural damage. 506 00:24:26,600 --> 00:24:28,669 [serious music] 507 00:24:28,769 --> 00:24:30,504 [Jay] To counteract the effect of the wind, 508 00:24:30,604 --> 00:24:32,706 the engineers come up with a plan. 509 00:24:33,907 --> 00:24:37,077 Each leg is built with a double-skin steel wall. 510 00:24:37,178 --> 00:24:41,047 Between them, tension cables are run from top to bottom. 511 00:24:42,482 --> 00:24:45,585 These cables are tightened enough to provide stability, 512 00:24:45,686 --> 00:24:47,922 but still allow the legs to move, 513 00:24:48,022 --> 00:24:49,656 absorbing the force of the wind 514 00:24:49,756 --> 00:24:52,525 and preventing it from causing structural damage. 515 00:24:54,194 --> 00:24:58,665 It was designed that it will sway up to 18 inches. 516 00:24:58,799 --> 00:25:00,834 That'd be nine inches either side. 517 00:25:00,934 --> 00:25:04,704 And it's built to withstand up to 150-mile-an-hour winds. 518 00:25:06,740 --> 00:25:09,576 [Jay] Incredibly, the men building it are doing so 519 00:25:09,676 --> 00:25:11,345 hundreds of feet above the ground 520 00:25:11,445 --> 00:25:14,548 in a time where no one wore safety harnesses. 521 00:25:16,483 --> 00:25:19,253 I honestly didn't know how dangerous it was 522 00:25:19,353 --> 00:25:22,522 until I took my first step up to that platform. 523 00:25:22,622 --> 00:25:24,825 I was almost petrified. 524 00:25:24,925 --> 00:25:27,395 It seemed like every time we did something, 525 00:25:27,495 --> 00:25:29,730 there was something scary gonna happen. 526 00:25:29,863 --> 00:25:35,735 It was the first job that I was afraid every single day. 527 00:25:36,570 --> 00:25:38,739 [Dr. Mabry] It's literally insane. 528 00:25:39,006 --> 00:25:41,408 You're working 600 feet up, 529 00:25:41,508 --> 00:25:45,011 facing winds, and focusing on doing your job. 530 00:25:45,846 --> 00:25:48,749 One lapse in concentration, one slip, 531 00:25:49,183 --> 00:25:51,117 you'll be facing certain death. 532 00:25:52,886 --> 00:25:54,521 [Kirk] The insurance companies predicted that 533 00:25:54,622 --> 00:25:56,823 they were gonna have 12 or 13 deaths 534 00:25:56,923 --> 00:25:58,391 during the construction. 535 00:26:00,327 --> 00:26:01,929 They had zero. 536 00:26:02,029 --> 00:26:04,798 [calm music] 537 00:26:04,931 --> 00:26:08,402 [Jay] In October 1965, three years into the build, 538 00:26:08,502 --> 00:26:10,370 they are ready to complete the arch. 539 00:26:10,737 --> 00:26:12,573 It's the moment of truth. 540 00:26:13,273 --> 00:26:17,111 Success all comes down to those two legs meeting in the middle. 541 00:26:17,211 --> 00:26:20,580 If they don't, it's total failure. 542 00:26:20,680 --> 00:26:27,787 [upbeat percussion music] 543 00:26:30,424 --> 00:26:32,359 [awe-inspiring music] 544 00:26:32,459 --> 00:26:34,127 [Jay] In Saint Louis, Missouri, 545 00:26:34,227 --> 00:26:35,762 the team building the Gateway Arch 546 00:26:35,862 --> 00:26:37,131 are holding their breath 547 00:26:37,231 --> 00:26:39,633 as they fit the final section of steel. 548 00:26:40,701 --> 00:26:43,437 And they knew they had to be within 1/32 of an inch 549 00:26:43,570 --> 00:26:45,105 in order to make it all work. 550 00:26:46,173 --> 00:26:47,374 The pressure was on. 551 00:26:47,474 --> 00:26:49,777 After all this time and all this effort, 552 00:26:49,910 --> 00:26:52,046 all these thousands of people working for years, 553 00:26:52,146 --> 00:26:54,181 everything comes down to this one moment. 554 00:26:54,915 --> 00:26:56,750 [Jay] To make things even more difficult... 555 00:26:57,851 --> 00:27:01,154 Fitting the last piece is a race against the clock. 556 00:27:02,156 --> 00:27:04,024 [Jennifer] They knew they had about 45 minutes 557 00:27:04,124 --> 00:27:06,193 before the sun's heat would make it impossible 558 00:27:06,293 --> 00:27:08,328 for the last piece to fit into place. 559 00:27:08,428 --> 00:27:10,965 The sun was warmin' up the south leg enough 560 00:27:11,065 --> 00:27:13,166 to where they would not fit in. 561 00:27:14,435 --> 00:27:18,239 [Jay] With time running out, they call in reinforcements. 562 00:27:18,572 --> 00:27:20,174 [dramatic music] 563 00:27:20,307 --> 00:27:21,608 They had the fire department come in 564 00:27:21,708 --> 00:27:23,644 to start hosin' down the south leg to cool it off 565 00:27:23,744 --> 00:27:26,646 so it opened up enough to drop that final piece in. 566 00:27:28,015 --> 00:27:30,250 [Man] The leg's comin' up, Bill. 567 00:27:30,350 --> 00:27:37,357 [dramatic music] 568 00:27:37,958 --> 00:27:39,159 [Jay] Against the odds... 569 00:27:39,259 --> 00:27:41,528 [dramatic music] 570 00:27:41,662 --> 00:27:43,463 [Jay] ...the arch is complete. 571 00:27:43,563 --> 00:27:50,271 [dramatic music] 572 00:27:50,371 --> 00:27:52,339 [Jay] In June 1967, 573 00:27:52,473 --> 00:27:54,541 five years after construction began, 574 00:27:54,641 --> 00:27:57,844 the magnificent monument opens to the public. 575 00:27:58,279 --> 00:28:01,581 [uplifting music] 576 00:28:01,681 --> 00:28:04,351 [Jay] A specially-built tram hidden inside the legs 577 00:28:04,451 --> 00:28:07,187 is ready to carry over a million people a year 578 00:28:07,287 --> 00:28:11,258 up to a spectacular view overlooking the city. 579 00:28:12,426 --> 00:28:16,096 Saarinen's daughter was one of the first to enjoy it. 580 00:28:16,430 --> 00:28:19,500 The first time I went up the arch, 581 00:28:19,600 --> 00:28:22,969 I looked down at Saint Louis, 582 00:28:23,637 --> 00:28:29,409 and I couldn't believe how emotional I could feel, 583 00:28:30,076 --> 00:28:32,946 um, looking through those little windows. 584 00:28:33,580 --> 00:28:39,219 [awe-inspiring music] 585 00:28:39,986 --> 00:28:41,488 It's a beautiful sight. 586 00:28:43,090 --> 00:28:44,892 It's somethin' to be proud of, 587 00:28:44,992 --> 00:28:48,762 and for me, it's a silver rainbow. 588 00:28:49,329 --> 00:28:51,898 Yeah, a silver rainbow. 589 00:28:53,033 --> 00:28:56,370 [Jay] Its 630 feet of towering triangular steel 590 00:28:56,470 --> 00:28:59,540 elegantly frames historic Saint Louis, 591 00:28:59,640 --> 00:29:03,144 giving the city back its sense of pride. 592 00:29:03,244 --> 00:29:05,712 The Gateway Arch was built to put Saint Louis 593 00:29:05,812 --> 00:29:06,646 back on the map, 594 00:29:06,780 --> 00:29:08,482 and wow, did it do that. 595 00:29:08,983 --> 00:29:10,484 [Ted] This thing is beautiful, 596 00:29:10,584 --> 00:29:14,221 and people still come by the millions to view it. 597 00:29:14,321 --> 00:29:16,290 And that makes me proud. 598 00:29:16,390 --> 00:29:27,634 [empowering music] 599 00:29:30,170 --> 00:29:36,443 [upbeat percussion music] 600 00:29:38,812 --> 00:29:42,549 What do you call a triangular glass office block building 601 00:29:42,649 --> 00:29:43,984 built, constructed on 602 00:29:44,118 --> 00:29:46,854 a contaminated World War II reclaimed plane fuel depot, 603 00:29:46,954 --> 00:29:50,891 which appears to float above a gigantic concrete pedestal 604 00:29:50,958 --> 00:29:53,627 and has stunning views all the way to Sweden? 605 00:29:53,961 --> 00:29:56,163 Soundport. Sounds good. 606 00:29:56,664 --> 00:29:59,332 Yeah, it does, and it looks even better. 607 00:30:00,067 --> 00:30:02,135 [serious music] 608 00:30:02,235 --> 00:30:06,073 [Jay] Copenhagen in Denmark is regularly ranked as 609 00:30:06,173 --> 00:30:08,008 one of Europe's happiest cities 610 00:30:08,108 --> 00:30:12,146 thanks to its clean air, healthy lifestyle, 611 00:30:12,279 --> 00:30:14,548 and great work-life balance. 612 00:30:15,316 --> 00:30:17,484 So, it's no wonder that when one of 613 00:30:17,584 --> 00:30:19,620 the world's biggest pharmaceutical companies 614 00:30:19,753 --> 00:30:22,890 wanted a striking new research and design center, 615 00:30:23,190 --> 00:30:24,958 they chose to build it here. 616 00:30:25,058 --> 00:30:30,263 [dramatic music] 617 00:30:30,363 --> 00:30:33,400 [Jay] Their new home is a gleaming triangular building 618 00:30:33,500 --> 00:30:36,803 that rises up from the Copenhagen waterfront. 619 00:30:38,205 --> 00:30:40,207 It stops you in your tracks. 620 00:30:40,274 --> 00:30:42,943 It looks like the most beautifully designed ship 621 00:30:43,043 --> 00:30:44,545 ready to launch out to sea. 622 00:30:45,412 --> 00:30:48,449 [Jay] Constructing it on this tiny triangular plot, though, 623 00:30:48,549 --> 00:30:51,384 meant overcoming some serious problems. 624 00:30:52,285 --> 00:30:53,954 It was a, a challenging site. 625 00:30:54,087 --> 00:30:55,355 It's an alienated island. 626 00:30:55,455 --> 00:30:57,658 No space around the, uh, building. 627 00:30:57,758 --> 00:30:59,293 [Jay] The land was contaminated, 628 00:30:59,393 --> 00:31:01,996 the ground not strong enough to build on. 629 00:31:02,096 --> 00:31:03,897 It's impossible, what we've done. 630 00:31:04,031 --> 00:31:05,399 Absolutely impossible. 631 00:31:05,633 --> 00:31:07,000 [Jay] Against all odds, 632 00:31:07,100 --> 00:31:10,537 the team created a 360,000-square-foot building 633 00:31:10,671 --> 00:31:13,240 with astonishing views out to sea. 634 00:31:15,175 --> 00:31:17,778 Flooded with light from a dome glass ceiling 635 00:31:17,878 --> 00:31:21,114 made up of 638 individual panes. 636 00:31:23,017 --> 00:31:25,385 This is Soundport. 637 00:31:27,554 --> 00:31:30,123 So, how'd they build it? 638 00:31:30,190 --> 00:31:35,662 [intriguing music] 639 00:31:35,762 --> 00:31:37,197 [Jay] Back in the 1950s, 640 00:31:37,297 --> 00:31:40,067 Ferring was a small Swedish pharmaceutical company 641 00:31:40,200 --> 00:31:42,068 operating out of two rooms. 642 00:31:43,970 --> 00:31:46,606 Fast forward 60 years to the 2010s, 643 00:31:46,706 --> 00:31:47,874 and it's become one of 644 00:31:48,008 --> 00:31:49,843 the biggest pharma names in Scandinavia, 645 00:31:49,943 --> 00:31:52,546 with offices worldwide. 646 00:31:53,814 --> 00:31:56,983 They decide to build a new research and development center 647 00:31:57,083 --> 00:31:58,386 in Denmark. 648 00:31:58,519 --> 00:32:00,287 To do it, they bring in one of the world's 649 00:32:00,387 --> 00:32:03,290 most influential architecture practices, 650 00:32:03,391 --> 00:32:05,259 Foster Partners, 651 00:32:05,759 --> 00:32:08,495 responsible for the Millau Viaduct in France 652 00:32:08,595 --> 00:32:10,797 and the Gherkin in London. 653 00:32:12,032 --> 00:32:13,467 We're trying to do something for them 654 00:32:13,600 --> 00:32:15,135 that can be really extraordinary. 655 00:32:15,235 --> 00:32:18,872 And to have a client who's trusting you to do something 656 00:32:18,972 --> 00:32:20,441 that they see as really important to them 657 00:32:20,541 --> 00:32:23,076 and the future of their business and also to their history, 658 00:32:23,710 --> 00:32:27,347 that's a real pressure, pressure as a designer. 659 00:32:28,615 --> 00:32:31,318 [Jay] What's more, the client has fallen in love 660 00:32:31,418 --> 00:32:34,622 with a site with wonderful views back over the water 661 00:32:34,722 --> 00:32:36,957 to Sweden, where the company was founded. 662 00:32:38,225 --> 00:32:40,093 But while the views might be good, 663 00:32:40,594 --> 00:32:43,263 the plot is an awkward triangular shape, 664 00:32:43,363 --> 00:32:47,000 and that's only the beginning of its challenges. 665 00:32:47,767 --> 00:32:50,905 [upbeat music] 666 00:32:51,005 --> 00:32:52,105 [Jay] The first problem to solve 667 00:32:52,239 --> 00:32:54,341 will be building a foundation system 668 00:32:54,441 --> 00:32:55,876 that can keep water out 669 00:32:55,942 --> 00:32:57,878 and support the weight of the building 670 00:32:57,978 --> 00:32:59,779 on the waterlogged site. 671 00:33:02,049 --> 00:33:04,151 Then, the design will need to squeeze 672 00:33:04,284 --> 00:33:08,689 as much office space as possible onto the triangular-shaped plot. 673 00:33:09,190 --> 00:33:10,791 That will mean finding clever ways 674 00:33:10,891 --> 00:33:14,494 to support a building that widens as it rises. 675 00:33:14,594 --> 00:33:18,565 [upbeat music] 676 00:33:18,665 --> 00:33:21,201 [Jay] Finally, they'll need to devise a roof structure 677 00:33:21,335 --> 00:33:26,006 that will look both beautiful and give office workers 678 00:33:26,106 --> 00:33:28,409 as much natural light as possible, 679 00:33:28,509 --> 00:33:31,144 even in the dark Danish winters. 680 00:33:31,244 --> 00:33:34,815 [intriguing music] 681 00:33:34,915 --> 00:33:37,151 [serious music] 682 00:33:37,284 --> 00:33:38,786 [Jay] It's September 2016, 683 00:33:38,886 --> 00:33:40,854 and before they can even break ground, 684 00:33:40,954 --> 00:33:43,324 they had their first challenge to overcome. 685 00:33:43,424 --> 00:33:46,193 [serious music] 686 00:33:46,293 --> 00:33:48,529 [Jay] As is happening more and more around the world, 687 00:33:48,662 --> 00:33:50,697 to protect unspoiled countryside, 688 00:33:51,198 --> 00:33:53,334 the plan here is to redevelop land 689 00:33:53,434 --> 00:33:55,268 that's been used in the past. 690 00:33:56,637 --> 00:33:59,439 That's if it can be made safe to build on. 691 00:34:01,242 --> 00:34:03,477 [Andrea] That existing piece of land 692 00:34:03,944 --> 00:34:06,847 was dating back to the Second World War, 693 00:34:06,947 --> 00:34:10,483 and had been used as, uh, chemical storage. 694 00:34:11,719 --> 00:34:13,687 [Jay] During the Second World War, 695 00:34:13,987 --> 00:34:16,056 chemicals were stored here, 696 00:34:16,590 --> 00:34:19,292 and traces still remain in the soil. 697 00:34:20,394 --> 00:34:21,795 You have to take building on 698 00:34:21,895 --> 00:34:24,231 contaminated land very seriously. 699 00:34:25,399 --> 00:34:28,803 [Jay] On this site, that's particularly complicated. 700 00:34:29,537 --> 00:34:31,972 The potential for things going horribly wrong 701 00:34:32,038 --> 00:34:35,008 increases exponentially if you're excavating near water. 702 00:34:35,109 --> 00:34:38,345 Hazardous pollutants leaking into rivers, lakes, the sea, 703 00:34:38,445 --> 00:34:41,815 or groundwater suddenly have the potential to wreak havoc. 704 00:34:42,917 --> 00:34:45,586 [Jay] Not only do they need to make sure no contaminants 705 00:34:45,686 --> 00:34:48,088 leak into the sea and harm marine life... 706 00:34:49,756 --> 00:34:51,892 ...but the waterlogged soil isn't strong enough 707 00:34:51,992 --> 00:34:54,761 to support the weight of the huge new building. 708 00:34:56,096 --> 00:34:57,932 The ground is so weak, 709 00:34:58,032 --> 00:34:59,699 that if you tried to build on it, 710 00:35:00,100 --> 00:35:03,637 there's a risk that the plot starts to sink into the sea. 711 00:35:05,239 --> 00:35:07,007 [Jay] They decided to surround the island 712 00:35:07,140 --> 00:35:09,843 with a steel wall hammered into the ground. 713 00:35:11,612 --> 00:35:13,981 This should stop the land from collapsing, 714 00:35:14,081 --> 00:35:16,983 and prevent contaminants from leaking into the sea. 715 00:35:18,852 --> 00:35:20,754 But there's a problem. 716 00:35:22,055 --> 00:35:24,992 Water is still trickling in through the gaps in 717 00:35:25,092 --> 00:35:26,360 the sheet piling. 718 00:35:26,961 --> 00:35:29,463 [Jay] One solution is to send divers in 719 00:35:29,563 --> 00:35:31,165 to weld the sheets underwater. 720 00:35:31,599 --> 00:35:33,934 But the costs are mind-blowing. 721 00:35:34,768 --> 00:35:37,170 It was more or less more than one million. 722 00:35:37,270 --> 00:35:39,973 Uh, extra, extra, extra money. 723 00:35:41,508 --> 00:35:44,645 [Jay] How will they avoid completely blowing their budget? 724 00:35:44,778 --> 00:35:46,613 [percussion music] 725 00:35:49,750 --> 00:35:51,618 [Jay] In Copenhagen, Denmark, 726 00:35:52,753 --> 00:35:55,022 the team tasked with building 727 00:35:55,122 --> 00:35:57,391 a new research and development center 728 00:35:57,491 --> 00:36:01,962 are struggling to stop seawater flooding into the foundations. 729 00:36:02,062 --> 00:36:04,798 Luckily, the project's Italian engineers 730 00:36:04,932 --> 00:36:06,433 come to the rescue. 731 00:36:06,834 --> 00:36:09,937 Our company work many times in Venice. 732 00:36:10,070 --> 00:36:13,907 And in Venice, you are always by the sea. 733 00:36:14,007 --> 00:36:16,576 One thing that we have learned, working in this environment, 734 00:36:16,710 --> 00:36:18,612 was to seal the sheet piling with, 735 00:36:18,745 --> 00:36:22,015 with a mix of cement and wood. 736 00:36:22,582 --> 00:36:25,519 [Jay] The team sprays a blend of concrete and sawdust 737 00:36:25,619 --> 00:36:27,687 along the perimeter of the steel wall. 738 00:36:28,321 --> 00:36:30,190 The tide does the rest, 739 00:36:30,290 --> 00:36:33,694 pulling this into all the gaps, which then seal. 740 00:36:34,128 --> 00:36:36,129 [Dr. Mabry] It's an amazing solution. 741 00:36:36,229 --> 00:36:38,098 That's the best kind of engineering. 742 00:36:38,232 --> 00:36:42,836 The sawdust/cement mix creates kind of a slurry 743 00:36:42,936 --> 00:36:44,404 that's more like clay. 744 00:36:44,504 --> 00:36:48,241 It can mold itself and better fit in and seal gaps. 745 00:36:48,608 --> 00:36:52,279 An ingenious idea that saved millions of dollars. 746 00:36:53,914 --> 00:36:55,815 [Jay] With the island sealed from the sea, 747 00:36:55,916 --> 00:36:57,517 in December 2017, 748 00:36:57,617 --> 00:36:59,653 they begin the job of creating the foundations 749 00:36:59,753 --> 00:37:03,324 and making the site safe from the contaminated soil. 750 00:37:03,991 --> 00:37:07,127 The strategy they chose to fix it is called capping. 751 00:37:07,194 --> 00:37:10,530 Essentially, it's sealing the whole site in concrete. 752 00:37:12,433 --> 00:37:14,034 [Jay] It's a simple solution, 753 00:37:14,134 --> 00:37:18,872 but one that involves pouring 7,800 cubic yards of concrete. 754 00:37:20,373 --> 00:37:23,243 Now, they're finally ready to start working on 755 00:37:23,343 --> 00:37:24,645 the building itself. 756 00:37:24,745 --> 00:37:28,148 [serious music] 757 00:37:28,248 --> 00:37:31,685 [Jay] To fit enough office space onto the tiny spit of island, 758 00:37:31,818 --> 00:37:34,555 the building needs to be bigger than the plot. 759 00:37:34,655 --> 00:37:36,991 The architects have cleverly designed it 760 00:37:37,124 --> 00:37:39,126 to get wider as it rises, 761 00:37:39,226 --> 00:37:41,829 with each floor larger than the one underneath. 762 00:37:42,430 --> 00:37:45,532 The trouble is supporting the floors during construction 763 00:37:45,632 --> 00:37:48,235 takes an extraordinary amount of scaffolding. 764 00:37:48,635 --> 00:37:52,273 It was pretty impacting to see the west corner 765 00:37:52,373 --> 00:37:54,341 as it was being built, 766 00:37:54,441 --> 00:37:59,013 as the scaffolding and the necessary props were added. 767 00:37:59,146 --> 00:38:04,050 In the end, it was certainly a project within the project. 768 00:38:04,985 --> 00:38:07,153 [Jay] The next challenge is devising a way of 769 00:38:07,254 --> 00:38:10,190 holding up these floors permanently. 770 00:38:11,926 --> 00:38:14,661 The client doesn't want the look of the building spoiled 771 00:38:14,761 --> 00:38:16,030 with a lot of columns. 772 00:38:16,530 --> 00:38:20,000 Instead, they come up with an ingenious solution. 773 00:38:20,468 --> 00:38:22,403 Hidden further back in the building 774 00:38:22,503 --> 00:38:23,871 are giant concrete cores, 775 00:38:24,004 --> 00:38:26,841 supporting chunky horizontal trusses. 776 00:38:26,941 --> 00:38:28,742 Steel rods will hang from these 777 00:38:28,842 --> 00:38:31,378 to support the floors from above. 778 00:38:31,979 --> 00:38:35,916 [serious music] 779 00:38:36,016 --> 00:38:37,584 [Jay] Before the scaffolding can be removed, 780 00:38:37,684 --> 00:38:38,985 the rods must be tightened 781 00:38:39,085 --> 00:38:41,121 to create the precise amount of tension needed 782 00:38:41,221 --> 00:38:42,622 to hold the floors' weight. 783 00:38:43,924 --> 00:38:46,394 They have to carefully adjust each of the bolts, 784 00:38:46,494 --> 00:38:48,428 securing each rod in turn, 785 00:38:48,528 --> 00:38:51,398 monitoring the tension the entire time. 786 00:38:51,831 --> 00:38:54,267 [Jay] If the rods end up too taut or too slack, 787 00:38:54,401 --> 00:38:57,738 there's a danger the floors will crack or even collapse. 788 00:38:58,138 --> 00:38:59,539 It's a tense moment for the team, 789 00:38:59,639 --> 00:39:01,909 led by Pietro Boerio. 790 00:39:02,543 --> 00:39:04,812 I was obviously on the top of the building, of the floor 791 00:39:04,945 --> 00:39:09,683 when, when, uh, we, uh, we make the tensioning. 792 00:39:09,783 --> 00:39:11,117 Because... 793 00:39:11,618 --> 00:39:13,020 Like... 794 00:39:13,120 --> 00:39:16,656 the, the captain of the ship, when the ship go down, 795 00:39:16,790 --> 00:39:18,659 the captain go down, no? 796 00:39:18,759 --> 00:39:22,229 The same! I was at the top of the building. 797 00:39:23,864 --> 00:39:27,434 [Jay] Thankfully, all goes the plan. 798 00:39:28,903 --> 00:39:31,572 And with the rods successfully tightened, 799 00:39:31,672 --> 00:39:33,206 the build continues. 800 00:39:35,509 --> 00:39:37,210 The next challenge the team faces 801 00:39:37,310 --> 00:39:40,180 is making sure the building lets in enough light. 802 00:39:41,515 --> 00:39:43,116 In winter, Copenhagen can get 803 00:39:43,216 --> 00:39:46,086 as little as seven hours of daylight. 804 00:39:46,186 --> 00:39:48,488 A problem that Danish building rules 805 00:39:48,622 --> 00:39:50,590 take very seriously. 806 00:39:50,690 --> 00:39:53,627 There's a lot of regulations, uh, like in many countries. 807 00:39:53,727 --> 00:39:57,330 But for, for Denmark, I, I find them maybe a little bit tougher. 808 00:39:57,998 --> 00:39:59,466 [David] It means, effectively, 809 00:39:59,599 --> 00:40:02,202 that every desk has to have a minimum daylight on it, 810 00:40:02,302 --> 00:40:06,206 and every worker at a desk needs to have daylight and views. 811 00:40:06,640 --> 00:40:08,642 What it means is you can't have a desk 812 00:40:08,742 --> 00:40:11,444 more than six meters away from a window. 813 00:40:12,880 --> 00:40:15,916 [Jay] It's easy to get light along the edges of the building 814 00:40:16,016 --> 00:40:17,584 by glazing the external walls. 815 00:40:18,084 --> 00:40:20,621 But it's a challenge bringing it to the center, 816 00:40:21,054 --> 00:40:23,457 particularly with the low winter sun. 817 00:40:24,324 --> 00:40:28,061 The solution is an atrium, but not any old atrium. 818 00:40:29,062 --> 00:40:31,665 So, atriums don't let in very much daylight. 819 00:40:31,798 --> 00:40:33,133 If we're gonna do an atrium, 820 00:40:33,267 --> 00:40:35,402 we have to reoptimize its potential to, 821 00:40:35,503 --> 00:40:37,771 to let in as much daylight as possible. 822 00:40:39,673 --> 00:40:41,608 [Jay] Whatever they build needs to cover an area 823 00:40:41,708 --> 00:40:43,944 of 17,000 square feet. 824 00:40:44,611 --> 00:40:47,914 That's a lot of glass and a lot of weight to support. 825 00:40:48,615 --> 00:40:49,950 [David] If you put a beam across, 826 00:40:50,083 --> 00:40:51,584 it would be over two meters deep. 827 00:40:51,685 --> 00:40:52,953 So, obviously that's not going to work 828 00:40:53,053 --> 00:40:54,755 and give you the kind of transparency. 829 00:40:55,222 --> 00:40:57,124 [Jay] Luckily, the architects are experts 830 00:40:57,257 --> 00:40:59,459 when it comes to beautiful glass roofs. 831 00:41:01,695 --> 00:41:03,464 In 2000, Foster Partners 832 00:41:03,564 --> 00:41:05,499 covered the British Museum in London 833 00:41:05,599 --> 00:41:07,567 with a structure known as gridshell. 834 00:41:08,435 --> 00:41:09,770 Like an egg, 835 00:41:09,870 --> 00:41:12,373 a gridshell's curved shape makes it very strong, 836 00:41:12,473 --> 00:41:15,208 which means it can have the least amount of structure 837 00:41:15,342 --> 00:41:17,244 with the most amount of glass. 838 00:41:17,344 --> 00:41:19,179 The simplest way to make one 839 00:41:19,279 --> 00:41:22,849 is to stitch together a lot of flat triangles. 840 00:41:23,417 --> 00:41:24,585 They are simple shapes, 841 00:41:24,685 --> 00:41:27,454 and can more easily tile complex surfaces 842 00:41:27,554 --> 00:41:29,056 without needing to bend, 843 00:41:29,190 --> 00:41:31,358 as any three points of the triangle 844 00:41:31,458 --> 00:41:33,627 can lie flat on a curved surface. 845 00:41:35,929 --> 00:41:37,064 [Jay] This time, though, 846 00:41:37,164 --> 00:41:38,965 they wanna let even more light in 847 00:41:39,066 --> 00:41:43,003 by reducing the amount of steel and creating bigger panes. 848 00:41:44,237 --> 00:41:46,840 To do it, they decided to make their gridshell 849 00:41:46,940 --> 00:41:49,944 using four-sided shapes, or quadrangles. 850 00:41:50,444 --> 00:41:53,046 But that brings with it the next major challenge. 851 00:41:54,615 --> 00:41:58,318 For a quadrangle to adapt to a curved surface, 852 00:41:58,419 --> 00:42:01,488 at least one of its sides needs to bend. 853 00:42:03,357 --> 00:42:05,759 [Jay] Traditionally, bent glass would have to be 854 00:42:05,859 --> 00:42:07,695 manufactured using heat. 855 00:42:08,362 --> 00:42:11,031 Making the vast number of different-shaped pieces 856 00:42:11,131 --> 00:42:13,433 required for a roof as complex as this 857 00:42:14,101 --> 00:42:17,437 would be expensive and energy intensive. 858 00:42:17,571 --> 00:42:20,007 So, they turn to a pioneering method 859 00:42:20,107 --> 00:42:21,741 called cold bending. 860 00:42:22,342 --> 00:42:23,677 [David] Cold bending, 861 00:42:23,744 --> 00:42:25,879 you're effectively mechanically pushing it down on, 862 00:42:25,979 --> 00:42:27,347 in, in situ. 863 00:42:27,448 --> 00:42:28,949 [Jay] Because it can be done on site, 864 00:42:29,083 --> 00:42:30,617 it's much cheaper. 865 00:42:30,717 --> 00:42:33,453 But forcing such a delicate material to bend 866 00:42:33,587 --> 00:42:36,390 requires painstaking planning. 867 00:42:36,490 --> 00:42:37,691 [David] So, glass has 868 00:42:37,792 --> 00:42:39,293 an inherent bending capacity in it, 869 00:42:39,393 --> 00:42:42,129 but there's a limit to how much it bends until it fails. 870 00:42:42,229 --> 00:42:44,265 So, it's really understanding that point. 871 00:42:44,365 --> 00:42:45,799 What is the maximum limit? 872 00:42:46,366 --> 00:42:47,735 [Jay] Having carefully calculated 873 00:42:47,835 --> 00:42:50,404 exactly how much pressure the glass can take, 874 00:42:50,938 --> 00:42:54,207 638 individual flat glass panels 875 00:42:54,307 --> 00:42:56,777 are carefully screwed into the curved frame, 876 00:42:56,910 --> 00:42:59,512 bending as they adapt to its shape. 877 00:43:00,246 --> 00:43:04,784 It takes 8,100 clamps and more than 16,000 screws, 878 00:43:04,885 --> 00:43:09,055 but at last, the roof is complete. 879 00:43:10,591 --> 00:43:13,126 [serious music] 880 00:43:13,226 --> 00:43:15,062 [Jay] In October 2022, 881 00:43:15,162 --> 00:43:18,165 Soundport opens its doors for business. 882 00:43:18,265 --> 00:43:21,802 [dynamic music] 883 00:43:21,902 --> 00:43:25,238 [Jay] It's taken 33,000 cubic yards of concrete, 884 00:43:25,672 --> 00:43:28,175 4,700 tons of steel, 885 00:43:28,275 --> 00:43:30,510 and nine years to get here. 886 00:43:32,345 --> 00:43:34,548 But now, it stands firm, 887 00:43:34,648 --> 00:43:38,018 looking out across the water to Sweden. 888 00:43:39,219 --> 00:43:43,957 As a piece of architecture, I think it's very, very good. 889 00:43:44,658 --> 00:43:46,526 [David] Many people who visit the building 890 00:43:46,626 --> 00:43:49,330 are very surprised between the outside and the inside. 891 00:43:49,463 --> 00:43:50,997 It's completely unexpected 892 00:43:51,097 --> 00:43:53,567 when they walk into that atrium space. 893 00:43:55,535 --> 00:43:57,838 [Mat] This is a dream breathed from a plan. 894 00:43:57,971 --> 00:44:00,340 Make the most of these great views on the water, 895 00:44:00,440 --> 00:44:02,376 and make sure the building's stunning. 896 00:44:02,476 --> 00:44:06,213 [serious music] 897 00:44:07,213 --> 00:44:18,058 [dramatic music] 898 00:44:18,158 --> 00:44:29,903 [dramatic choral music]