1 00:00:06,170 --> 00:00:04,030 [Music] 2 00:00:08,780 --> 00:00:06,180 welcome to tales from the rabbit hole 3 00:00:10,910 --> 00:00:08,790 I'm your host big words my guest today 4 00:00:12,950 --> 00:00:10,920 is Donald Friedman a licensed 5 00:00:14,959 --> 00:00:12,960 professional engineer with 30 years of 6 00:00:17,540 --> 00:00:14,969 experience as a structural engineer and 7 00:00:19,550 --> 00:00:17,550 also as a forensic engineer Dunn is a 8 00:00:20,960 --> 00:00:19,560 founder of old structures engineering 9 00:00:22,640 --> 00:00:20,970 and he's also taught at the Pratt 10 00:00:25,279 --> 00:00:22,650 Institute and various other places 11 00:00:27,050 --> 00:00:25,289 including Columbia University he's 12 00:00:29,150 --> 00:00:27,060 presented at conferences you've authored 13 00:00:31,669 --> 00:00:29,160 numerous articles and written five books 14 00:00:33,950 --> 00:00:31,679 related to construction renovation and 15 00:00:35,569 --> 00:00:33,960 engineering one of those books is an 16 00:00:38,750 --> 00:00:35,579 engineer's work at the World Trade 17 00:00:40,880 --> 00:00:38,760 Center published in 2002 which tells of 18 00:00:43,910 --> 00:00:40,890 his experience working as an engineer at 19 00:00:46,490 --> 00:00:43,920 the World Trade Center site after 9/11 I 20 00:00:48,229 --> 00:00:46,500 talked with him about how his experience 21 00:00:49,910 --> 00:00:48,239 at the World Trade Center and its 22 00:00:55,939 --> 00:00:49,920 knowledge of engineering intersects with 23 00:00:58,939 --> 00:00:55,949 the world of conspiracy theories okay 24 00:01:01,160 --> 00:00:58,949 right well first of all thanks again for 25 00:01:02,959 --> 00:01:01,170 doing this this is very good thanks for 26 00:01:05,509 --> 00:01:02,969 making the time you're welcome 27 00:01:06,590 --> 00:01:05,519 you are the author of the book an 28 00:01:09,350 --> 00:01:06,600 engineer's work at the World Trade 29 00:01:11,719 --> 00:01:09,360 Center which you published in 2002 which 30 00:01:13,990 --> 00:01:11,729 details your experience working as an 31 00:01:16,640 --> 00:01:14,000 engineer at the World Trade Center site 32 00:01:19,429 --> 00:01:16,650 how did that actually start can you can 33 00:01:21,080 --> 00:01:19,439 you say how you actually got onto the 34 00:01:23,780 --> 00:01:21,090 site like you know what's what happened 35 00:01:25,910 --> 00:01:23,790 in how you were assigned there at that 36 00:01:28,880 --> 00:01:25,920 time I was an employee of Thornton 37 00:01:30,590 --> 00:01:28,890 Thomas SETI engineers I was an associate 38 00:01:33,380 --> 00:01:30,600 and I was the director of historic 39 00:01:35,270 --> 00:01:33,390 preservation for the company and as my 40 00:01:39,170 --> 00:01:35,280 understanding of it is that on the 41 00:01:44,139 --> 00:01:39,180 afternoon of September 11th 2001 New 42 00:01:46,700 --> 00:01:44,149 York City hired Thorton Thomas Eddie to 43 00:01:49,730 --> 00:01:46,710 coordinate the engineering work that 44 00:01:51,289 --> 00:01:49,740 would be required for cleanup basically 45 00:01:53,840 --> 00:01:51,299 the city doesn't have enough structural 46 00:01:57,230 --> 00:01:53,850 engineers to do the job and they all 47 00:01:59,510 --> 00:01:57,240 have their regular work to do so if all 48 00:02:03,139 --> 00:01:59,520 of them were were on site nothing else 49 00:02:04,700 --> 00:02:03,149 would be happening so we were all of the 50 00:02:07,280 --> 00:02:04,710 employees in the Thorton Thomas city New 51 00:02:11,420 --> 00:02:07,290 York office were informed that afternoon 52 00:02:13,670 --> 00:02:11,430 that if we agreed to it it was 53 00:02:15,350 --> 00:02:13,680 voluntarily voluntary 54 00:02:19,550 --> 00:02:15,360 we would be going to the site the next 55 00:02:21,710 --> 00:02:19,560 day 12th and I volunteered the way it 56 00:02:24,289 --> 00:02:21,720 eventually was organized it took a few 57 00:02:26,839 --> 00:02:24,299 days for this to solidify was that there 58 00:02:29,330 --> 00:02:26,849 were at any given moment five teams on 59 00:02:31,460 --> 00:02:29,340 site there was one more or less 60 00:02:34,369 --> 00:02:31,470 stationed at each of the four corners of 61 00:02:38,319 --> 00:02:34,379 the site which is a slightly skewed 62 00:02:40,940 --> 00:02:38,329 trapezoid and my team was roving around 63 00:02:42,860 --> 00:02:40,950 looking for old buildings so there are a 64 00:02:45,349 --> 00:02:42,870 number of historic landmarks near the 65 00:02:47,420 --> 00:02:45,359 site and build some few buildings that 66 00:02:51,020 --> 00:02:47,430 are not landmarks but are not modern 67 00:02:54,080 --> 00:02:51,030 structure since that's my specialty okay 68 00:02:57,199 --> 00:02:54,090 we were going to be working on that so 69 00:02:59,539 --> 00:02:57,209 starting on the 12th I was down there as 70 00:03:02,210 --> 00:02:59,549 part of that effort I was there for nine 71 00:03:04,550 --> 00:03:02,220 I believe nine days in a row at the 72 00:03:06,679 --> 00:03:04,560 beginning and then every third or fourth 73 00:03:08,660 --> 00:03:06,689 day afterwards into November 74 00:03:11,360 --> 00:03:08,670 yeah my understanding of what engineer 75 00:03:13,490 --> 00:03:11,370 does is basically that you are studying 76 00:03:15,470 --> 00:03:13,500 a structure to determine the loads on 77 00:03:17,479 --> 00:03:15,480 that structure and to make sure that 78 00:03:19,009 --> 00:03:17,489 structure can support the loads and you 79 00:03:22,159 --> 00:03:19,019 know any additional loads that might 80 00:03:25,400 --> 00:03:22,169 come along and then design modifications 81 00:03:27,770 --> 00:03:25,410 or additional structures if needed to 82 00:03:28,970 --> 00:03:27,780 support those loads basically is that 83 00:03:31,460 --> 00:03:28,980 kind of a good kind of over the year 84 00:03:33,530 --> 00:03:31,470 what an engineer does it's certainly a 85 00:03:36,080 --> 00:03:33,540 big piece of it if you work primarily 86 00:03:37,699 --> 00:03:36,090 with existing buildings as I do the 87 00:03:39,589 --> 00:03:37,709 beginning of almost every project is an 88 00:03:42,110 --> 00:03:39,599 investigation of the existing building 89 00:03:44,719 --> 00:03:42,120 if we have drawings we need to see that 90 00:03:45,979 --> 00:03:44,729 they're correct and if we mostly find we 91 00:03:50,110 --> 00:03:45,989 don't have drawings we need to figure 92 00:03:52,550 --> 00:03:50,120 out what the structural systems are and 93 00:03:53,930 --> 00:03:52,560 whether we have drawings or not there's 94 00:03:55,430 --> 00:03:53,940 always the question of well what's the 95 00:03:58,550 --> 00:03:55,440 condition of the existing building 96 00:04:01,129 --> 00:03:58,560 because all materials age and gradually 97 00:04:02,899 --> 00:04:01,139 fall apart so just because the building 98 00:04:04,939 --> 00:04:02,909 is standing doesn't mean that all of the 99 00:04:07,699 --> 00:04:04,949 structure is in good condition right 100 00:04:08,990 --> 00:04:07,709 yeah like yes I know my apartments we 101 00:04:10,819 --> 00:04:09,000 got a lot of termites taking out 102 00:04:14,199 --> 00:04:10,829 structural beams and bringing an 103 00:04:16,969 --> 00:04:14,209 engineer to add on an extra steel beam 104 00:04:19,399 --> 00:04:16,979 you mentioned you do forensic 105 00:04:20,539 --> 00:04:19,409 engineering as well is that kind of like 106 00:04:22,810 --> 00:04:20,549 what you're talking about they're 107 00:04:24,760 --> 00:04:22,820 examining building is there is that like 108 00:04:27,290 --> 00:04:24,770 examining when something collapses 109 00:04:28,820 --> 00:04:27,300 forensic engineer is most often 110 00:04:31,760 --> 00:04:28,830 to figure out that the reason for 111 00:04:36,050 --> 00:04:31,770 collapse and the quartz has been being 112 00:04:37,790 --> 00:04:36,060 what it is who's responsible okay some 113 00:04:39,790 --> 00:04:37,800 things are truly accident some things 114 00:04:42,589 --> 00:04:39,800 are truly unavoidable but very often 115 00:04:44,930 --> 00:04:42,599 somebody has somehow made an error that 116 00:04:46,700 --> 00:04:44,940 led to a collapse so you would do a 117 00:04:49,969 --> 00:04:46,710 study and maybe get cold as an expert 118 00:04:51,649 --> 00:04:49,979 witness in a in litigation yes it's not 119 00:04:53,960 --> 00:04:51,659 the main focus of my work right yeah you 120 00:04:55,430 --> 00:04:53,970 do sometimes yes so when you when you 121 00:04:56,869 --> 00:04:55,440 first arrive there one of the things 122 00:04:59,119 --> 00:04:56,879 that you know struck me in the book I 123 00:05:01,459 --> 00:04:59,129 think struck a lot of people who were at 124 00:05:03,980 --> 00:05:01,469 the site was that the contents of the 125 00:05:06,499 --> 00:05:03,990 building by the air things like desks 126 00:05:09,589 --> 00:05:06,509 and things like that had largely 127 00:05:11,689 --> 00:05:09,599 vanished and you see at least these 128 00:05:14,629 --> 00:05:11,699 large beams and these big chunks of 129 00:05:16,129 --> 00:05:14,639 concrete and lots of dust but you know a 130 00:05:18,559 --> 00:05:16,139 lot of the structure had actually 131 00:05:20,089 --> 00:05:18,569 actually advantaged this is something 132 00:05:21,619 --> 00:05:20,099 that people point to sometimes as being 133 00:05:22,999 --> 00:05:21,629 like evidence of something like there 134 00:05:25,040 --> 00:05:23,009 was have been some kind of explosives in 135 00:05:27,249 --> 00:05:25,050 the building was this something that you 136 00:05:29,570 --> 00:05:27,259 know struck you at the time as being 137 00:05:31,399 --> 00:05:29,580 inexplicable or did it you're gonna make 138 00:05:34,279 --> 00:05:31,409 sense to you at the time it was 139 00:05:36,469 --> 00:05:34,289 surprising but I I'm talking about what 140 00:05:38,930 --> 00:05:36,479 I saw in sight I should or my thoughts 141 00:05:41,360 --> 00:05:38,940 on sight I should mention that you know 142 00:05:44,149 --> 00:05:41,370 I was talking to other engineers that I 143 00:05:45,890 --> 00:05:44,159 know pretty much the whole time so I 144 00:05:48,529 --> 00:05:45,900 can't necessarily say that everything I 145 00:05:49,760 --> 00:05:48,539 say is something I thought of first a 146 00:05:51,230 --> 00:05:49,770 lot of times it's sort of part of a 147 00:05:54,920 --> 00:05:51,240 group conversation they're not just 148 00:05:57,409 --> 00:05:54,930 reporting it to you now okay what became 149 00:06:00,920 --> 00:05:57,419 pretty clear after the first day on site 150 00:06:02,439 --> 00:06:00,930 was that the contents of World Trade 151 00:06:06,850 --> 00:06:02,449 Center one and two had been pulverized 152 00:06:11,570 --> 00:06:06,860 anything that could break was broken so 153 00:06:15,110 --> 00:06:11,580 what survived the collapse the collapses 154 00:06:18,920 --> 00:06:15,120 was ductile metal so you saw a pieces of 155 00:06:21,529 --> 00:06:18,930 steel you saw I saw wants a huge pile of 156 00:06:23,749 --> 00:06:21,539 elevator cable that must have come from 157 00:06:26,059 --> 00:06:23,759 one of the upper shafts and what's the 158 00:06:28,540 --> 00:06:26,069 other thing survived was paper because 159 00:06:31,279 --> 00:06:28,550 if you think about an office building 160 00:06:35,329 --> 00:06:31,289 most of the volume of space on the 161 00:06:37,730 --> 00:06:35,339 inside is air and as the floors pancake 162 00:06:39,960 --> 00:06:37,740 down that air has to go somewhere and it 163 00:06:41,880 --> 00:06:39,970 goes out so 164 00:06:45,120 --> 00:06:41,890 loose paper that was sitting on 165 00:06:48,660 --> 00:06:45,130 somebody's desk got blown out outwards 166 00:06:50,280 --> 00:06:48,670 as the forced pancake down as a result 167 00:06:52,620 --> 00:06:50,290 there was paper all over the place on 168 00:06:54,900 --> 00:06:52,630 top of this or mixed in with this very 169 00:06:58,650 --> 00:06:54,910 thick layer of dust that was pulverized 170 00:07:02,670 --> 00:06:58,660 concrete and gypsum board ceiling tiles 171 00:07:04,200 --> 00:07:02,680 things like that cubicles yeah um along 172 00:07:08,790 --> 00:07:04,210 with this the other thing that got 173 00:07:11,190 --> 00:07:08,800 pulverized were bodies yeah and I mean 174 00:07:14,850 --> 00:07:11,200 that's why they had to resort to DNA 175 00:07:16,770 --> 00:07:14,860 testing in order to identify bodies 176 00:07:18,840 --> 00:07:16,780 because you know something like dental 177 00:07:21,000 --> 00:07:18,850 records was was hopeless because well 178 00:07:23,070 --> 00:07:21,010 there weren't big enough pieces of 179 00:07:25,460 --> 00:07:23,080 bodies intact I don't think anybody's 180 00:07:28,680 --> 00:07:25,470 cleaning 3000 people vanished 181 00:07:31,680 --> 00:07:28,690 no no it's yeah it's quite amazing to 182 00:07:33,030 --> 00:07:31,690 think and when you when you got there 183 00:07:34,860 --> 00:07:33,040 when you first got to the site what were 184 00:07:39,300 --> 00:07:34,870 the first engineering tasks that needed 185 00:07:41,340 --> 00:07:39,310 doing on the site on the 12th so if you 186 00:07:43,200 --> 00:07:41,350 think about it everybody knew three 187 00:07:45,180 --> 00:07:43,210 large buildings collapsed everybody knew 188 00:07:48,690 --> 00:07:45,190 a number of smaller buildings were hit 189 00:07:51,480 --> 00:07:48,700 by rubble hit by debris but nobody knew 190 00:07:54,090 --> 00:07:51,490 how you know did debris hit buildings a 191 00:07:57,200 --> 00:07:54,100 block away two blocks away there's no 192 00:08:00,390 --> 00:07:57,210 way to tell so what was the only thing 193 00:08:02,310 --> 00:08:00,400 engineers were doing on the 12th was 194 00:08:04,350 --> 00:08:02,320 looking at the building's sort of the 195 00:08:07,020 --> 00:08:04,360 perimeter of the site and the original 196 00:08:08,850 --> 00:08:07,030 perimeter was quite large it went two 197 00:08:11,880 --> 00:08:08,860 blocks to the east so it went a block 198 00:08:15,659 --> 00:08:11,890 east of Broadway for example at which 199 00:08:17,580 --> 00:08:15,669 point you're I don't know 200 yards from 200 00:08:19,770 --> 00:08:17,590 the site all right but if you think of 201 00:08:22,800 --> 00:08:19,780 that that is you know less than the 202 00:08:24,690 --> 00:08:22,810 height of the towers yeah so it's not 203 00:08:27,450 --> 00:08:24,700 it's not a conceivable something could 204 00:08:31,950 --> 00:08:27,460 have gone that far so what we were all 205 00:08:33,779 --> 00:08:31,960 doing was investigating we're basically 206 00:08:35,880 --> 00:08:33,789 going up on the roofs of the of 207 00:08:36,930 --> 00:08:35,890 buildings and we just knew they were I 208 00:08:38,550 --> 00:08:36,940 think something like four or five 209 00:08:41,640 --> 00:08:38,560 hundred Billy's checked going up on the 210 00:08:45,540 --> 00:08:41,650 roof to see if there was any sign that 211 00:08:47,700 --> 00:08:45,550 something hit and for example the post 212 00:08:51,900 --> 00:08:47,710 office that's north of the of the site 213 00:08:53,400 --> 00:08:51,910 they found the engine of one an engine 214 00:08:56,400 --> 00:08:53,410 from one of the planes on the roof 215 00:08:59,939 --> 00:08:56,410 host office so obviously debris had 216 00:09:01,590 --> 00:08:59,949 moved around with it and and it you know 217 00:09:03,360 --> 00:09:01,600 if you have enough people do it 218 00:09:06,480 --> 00:09:03,370 methodically we went through a lot of 219 00:09:07,829 --> 00:09:06,490 buildings on the 12th and on the 13th so 220 00:09:10,410 --> 00:09:07,839 that was that was the first engineering 221 00:09:12,509 --> 00:09:10,420 tasks that would there were basically 222 00:09:14,490 --> 00:09:12,519 two groups of people from Thornton town 223 00:09:16,019 --> 00:09:14,500 a city it was one group of doing site 224 00:09:18,329 --> 00:09:16,029 work which is where I was pretty much 225 00:09:21,900 --> 00:09:18,339 the whole time and the other group was 226 00:09:23,910 --> 00:09:21,910 um checking where it was safe to put 227 00:09:25,980 --> 00:09:23,920 cranes because it was obvious the cranes 228 00:09:29,249 --> 00:09:25,990 were going to be needed to lift the 229 00:09:31,110 --> 00:09:29,259 heavier pieces of debris yeah so that 230 00:09:32,579 --> 00:09:31,120 was quite a big part of the well not big 231 00:09:35,100 --> 00:09:32,589 part of the book but you talked about it 232 00:09:37,559 --> 00:09:35,110 a lot like the the unusually large 233 00:09:39,509 --> 00:09:37,569 cranes that they had there now you talk 234 00:09:42,749 --> 00:09:39,519 about kind of going you started at the 235 00:09:46,050 --> 00:09:42,759 perimeter the farthest extent of the 236 00:09:48,360 --> 00:09:46,060 damage how would you characterize like 237 00:09:49,769 --> 00:09:48,370 what was actually at the perimeter in 238 00:09:51,119 --> 00:09:49,779 terms of what was falling you said you 239 00:09:52,410 --> 00:09:51,129 mentioned an engine that's obviously 240 00:09:55,110 --> 00:09:52,420 something that kind of shot out of the 241 00:09:58,829 --> 00:09:55,120 plane shut out so like yeah I'd be like 242 00:10:02,730 --> 00:09:58,839 exterior columns and the cladding of 243 00:10:05,819 --> 00:10:02,740 those columns I I didn't see anything 244 00:10:08,490 --> 00:10:05,829 like that when I saw at the so I only 245 00:10:11,249 --> 00:10:08,500 saw the buildings I checked and I was on 246 00:10:12,780 --> 00:10:11,259 Maiden Lane east of Broadway and some a 247 00:10:15,179 --> 00:10:12,790 couple of blocks close by which are 248 00:10:16,829 --> 00:10:15,189 quite far from the site and I think 249 00:10:20,340 --> 00:10:16,839 perhaps more importantly due to the east 250 00:10:21,900 --> 00:10:20,350 of the site and the planes that hit one 251 00:10:25,230 --> 00:10:21,910 was traveling north one was traveling 252 00:10:27,540 --> 00:10:25,240 south so any debris spread would not be 253 00:10:30,300 --> 00:10:27,550 likely to head east so what I saw on the 254 00:10:32,329 --> 00:10:30,310 roofs was the lightweight debris which 255 00:10:34,559 --> 00:10:32,339 is to say dust a little bit of paper 256 00:10:36,030 --> 00:10:34,569 okay moving further in towards the 257 00:10:38,069 --> 00:10:36,040 middle of the site you would see like 258 00:10:40,710 --> 00:10:38,079 start to see columns and beams and 259 00:10:42,480 --> 00:10:40,720 things noise and one of the things that 260 00:10:43,829 --> 00:10:42,490 really struck me in the bouquet which I 261 00:10:46,259 --> 00:10:43,839 mentioned in the email was your 262 00:10:47,850 --> 00:10:46,269 description of the core columns and how 263 00:10:50,460 --> 00:10:47,860 they had kind of snapped apart at the 264 00:10:53,340 --> 00:10:50,470 seams this is something that yes is 265 00:10:57,090 --> 00:10:53,350 something you observed quite a lot well 266 00:11:00,869 --> 00:10:57,100 yes the the steel from towers one and 267 00:11:02,850 --> 00:11:00,879 two really stayed within the footprint 268 00:11:04,259 --> 00:11:02,860 of the World Trade Center site I mean it 269 00:11:07,139 --> 00:11:04,269 went a little bit onto the surrounding 270 00:11:09,660 --> 00:11:07,149 streets but it's just too heavy 271 00:11:12,090 --> 00:11:09,670 it you know the the force pushing it 272 00:11:14,009 --> 00:11:12,100 outwards was just very small compared to 273 00:11:16,530 --> 00:11:14,019 gravity and therefore it went more or 274 00:11:18,509 --> 00:11:16,540 less straight down so you had to get up 275 00:11:20,670 --> 00:11:18,519 to the site right up to the world the 276 00:11:23,730 --> 00:11:20,680 World Trade Center site itself to see 277 00:11:28,829 --> 00:11:23,740 substantial amounts of Steel the 278 00:11:33,239 --> 00:11:28,839 farthest pieces of steel I saw were the 279 00:11:36,269 --> 00:11:33,249 ones stuck into guess it would be three 280 00:11:39,119 --> 00:11:36,279 World Financial Center and 130 Liberty 281 00:11:41,699 --> 00:11:39,129 Street so they had made it across West 282 00:11:44,220 --> 00:11:41,709 Street and across to the south side of 283 00:11:46,139 --> 00:11:44,230 the site and that's it's not it's not a 284 00:11:50,220 --> 00:11:46,149 negligible distance but that's about the 285 00:11:52,259 --> 00:11:50,230 furthest place Tony's feel ya know like 286 00:11:54,360 --> 00:11:52,269 I think a big part of why we get 287 00:11:56,429 --> 00:11:54,370 conspiracy theories about the collapses 288 00:11:58,559 --> 00:11:56,439 of the World Trade Center is that people 289 00:12:00,329 --> 00:11:58,569 don't understand how it could have 290 00:12:04,199 --> 00:12:00,339 collapsed they think is this incredibly 291 00:12:06,030 --> 00:12:04,209 strong structure and they think it's 292 00:12:07,949 --> 00:12:06,040 just highly implausible that even if 293 00:12:10,710 --> 00:12:07,959 there was damage at the top the 294 00:12:13,319 --> 00:12:10,720 progressive collapse would go all the 295 00:12:15,629 --> 00:12:13,329 way to the bottom is this something that 296 00:12:18,419 --> 00:12:15,639 you know when you used you know as you 297 00:12:21,689 --> 00:12:18,429 saw the original collapses you know on 298 00:12:26,699 --> 00:12:21,699 TV and you were on the site and you saw 299 00:12:29,309 --> 00:12:26,709 the results did you fairly quickly come 300 00:12:32,460 --> 00:12:29,319 to some kind of idea in your mind about 301 00:12:33,720 --> 00:12:32,470 how you thought the building collapsed 302 00:12:39,150 --> 00:12:33,730 was this something you gave much thought 303 00:12:41,780 --> 00:12:39,160 to do I I didn't give all our thoughts 304 00:12:44,939 --> 00:12:41,790 who a specific trigger for the collapse 305 00:12:48,210 --> 00:12:44,949 what everybody on site knew about the 306 00:12:50,879 --> 00:12:48,220 the towers 1 & 2 was that they had a 307 00:12:53,819 --> 00:12:50,889 relatively rigid exterior tube structure 308 00:12:56,850 --> 00:12:53,829 a bunch of columns and sort of normal 309 00:12:59,939 --> 00:12:56,860 floors in the core and in between were 310 00:13:01,410 --> 00:12:59,949 very long span trusses which are much 311 00:13:04,319 --> 00:13:01,420 lighter weight than the beams that might 312 00:13:06,419 --> 00:13:04,329 ordinarily be used all of the lateral 313 00:13:10,230 --> 00:13:06,429 rigidity is buildings was in the 314 00:13:12,090 --> 00:13:10,240 exterior so it's easy and it's in the 315 00:13:14,879 --> 00:13:12,100 case like that to see that once that no 316 00:13:17,069 --> 00:13:14,889 longer functions for whatever reason one 317 00:13:20,369 --> 00:13:17,079 reason being a big gaping hole where a 318 00:13:20,910 --> 00:13:20,379 plane hit the building that the interior 319 00:13:22,259 --> 00:13:20,920 of the building 320 00:13:26,370 --> 00:13:22,269 is not going to be strong enough to 321 00:13:28,290 --> 00:13:26,380 stand up if you had the plane impact 322 00:13:30,900 --> 00:13:28,300 with no fire if you can picture such a 323 00:13:32,670 --> 00:13:30,910 thing the towers would have stood up but 324 00:13:35,850 --> 00:13:32,680 they would have been extremely weak for 325 00:13:37,199 --> 00:13:35,860 lateral loading so that a 30 or 40 mile 326 00:13:40,650 --> 00:13:37,209 an hour wind might have been enough to 327 00:13:41,970 --> 00:13:40,660 bring them down because again the 328 00:13:44,550 --> 00:13:41,980 lateral system of the building was 329 00:13:48,900 --> 00:13:44,560 compromised by having a big section of 330 00:13:50,730 --> 00:13:48,910 it forcibly removed the floor trusses 331 00:13:52,889 --> 00:13:50,740 were for the most part unrecognizable 332 00:13:55,160 --> 00:13:52,899 they were just too weak and they 333 00:13:59,009 --> 00:13:55,170 crumpled up as the buildings collapsed 334 00:14:00,720 --> 00:13:59,019 the exterior columns are what made for 335 00:14:04,100 --> 00:14:00,730 other of the dramatic pictures that you 336 00:14:07,170 --> 00:14:04,110 saw in the news because they were 337 00:14:09,870 --> 00:14:07,180 assembled in sections and for the most 338 00:14:11,460 --> 00:14:09,880 part they they failed at the joints 339 00:14:14,460 --> 00:14:11,470 between sections and a section would be 340 00:14:17,610 --> 00:14:14,470 three columns so you see if you look at 341 00:14:19,530 --> 00:14:17,620 the original photographs afterwards you 342 00:14:21,600 --> 00:14:19,540 see a lot of three columns in a row 343 00:14:23,370 --> 00:14:21,610 that's the section of the original 344 00:14:26,850 --> 00:14:23,380 exterior and it broke apart at the 345 00:14:29,220 --> 00:14:26,860 splices well we're joined B where it 346 00:14:30,329 --> 00:14:29,230 joined the neighbouring sections it's 347 00:14:33,150 --> 00:14:30,339 interesting you mentioned like you know 348 00:14:35,870 --> 00:14:33,160 the lateral load is all on the exterior 349 00:14:38,100 --> 00:14:35,880 is that just talking about the wind load 350 00:14:40,560 --> 00:14:38,110 for the building I suppose in seismic 351 00:14:43,319 --> 00:14:40,570 loads but buildings were built before in 352 00:14:46,650 --> 00:14:43,329 New York City had earthquake load as 353 00:14:49,530 --> 00:14:46,660 part of its requirements so it didn't 354 00:14:52,319 --> 00:14:49,540 come in until 1996 so they were designed 355 00:14:55,860 --> 00:14:52,329 for wind they were designed for wind 356 00:14:57,329 --> 00:14:55,870 under the 1968 actually I think under 357 00:14:58,350 --> 00:14:57,339 the 68 Building Code the business 358 00:15:00,300 --> 00:14:58,360 they're old enough they may have been 359 00:15:01,650 --> 00:15:00,310 designed in 1938 don't think oh but I 360 00:15:04,079 --> 00:15:01,660 don't think so believe they were 361 00:15:05,639 --> 00:15:04,089 designed under the 68 opening code the 362 00:15:09,319 --> 00:15:05,649 wind loads are somewhat lower than would 363 00:15:12,240 --> 00:15:09,329 be required today not drastically so 364 00:15:13,290 --> 00:15:12,250 yeah I'm just want to make sure I 365 00:15:16,920 --> 00:15:13,300 understand like when you're talking 366 00:15:19,829 --> 00:15:16,930 about lateral loads like like say if you 367 00:15:22,650 --> 00:15:19,839 were to remove it delicately remove the 368 00:15:25,800 --> 00:15:22,660 exterior and the floors and you were 369 00:15:28,019 --> 00:15:25,810 just left with the core would that core 370 00:15:31,590 --> 00:15:28,029 column be able to the core of the 371 00:15:33,150 --> 00:15:31,600 building be self-supporting it would be 372 00:15:34,840 --> 00:15:33,160 self-supporting for gravity but it would 373 00:15:38,129 --> 00:15:34,850 basically be a house of cards 374 00:15:41,139 --> 00:15:38,139 very little lateral rigidity wow so a 375 00:15:45,039 --> 00:15:41,149 wind load much less than the code 376 00:15:48,099 --> 00:15:45,049 required wind vote in 1968 or now would 377 00:15:50,859 --> 00:15:48,109 that would be enough to destroy that so 378 00:15:52,989 --> 00:15:50,869 yeah it's what's called a tube structure 379 00:15:55,029 --> 00:15:52,999 it was invented in the 60s where you 380 00:15:56,499 --> 00:15:55,039 have closely spaced columns and beams 381 00:15:59,699 --> 00:15:56,509 would be at the exterior of the building 382 00:16:02,229 --> 00:15:59,709 and that serves as your lateral bracing 383 00:16:05,199 --> 00:16:02,239 John Hancock in Chicago is a tube 384 00:16:08,109 --> 00:16:05,209 structure there are any number from here 385 00:16:09,269 --> 00:16:08,119 in New York so it's it's a it was for a 386 00:16:12,400 --> 00:16:09,279 while 387 00:16:14,409 --> 00:16:12,410 sort of the the in vogue method of 388 00:16:16,449 --> 00:16:14,419 structural design for tall buildings 389 00:16:18,369 --> 00:16:16,459 yeah and that can make sense now like 390 00:16:19,809 --> 00:16:18,379 when when you think about how it 391 00:16:22,329 --> 00:16:19,819 collapsed like you talked about the 392 00:16:23,889 --> 00:16:22,339 floor trusses being all mangled 393 00:16:26,229 --> 00:16:23,899 like you there weren't very many 394 00:16:28,059 --> 00:16:26,239 recognizable floor trusses in the de 395 00:16:30,639 --> 00:16:28,069 rêve pile and they essentially would 396 00:16:32,799 --> 00:16:30,649 have been stripped away by the falling 397 00:16:35,919 --> 00:16:32,809 the falling mass of the building above 398 00:16:37,929 --> 00:16:35,929 in a very chaotic manner and then just 399 00:16:41,169 --> 00:16:37,939 reduced to rubble as they they went down 400 00:16:43,509 --> 00:16:41,179 yeah they were just crushed some people 401 00:16:46,149 --> 00:16:43,519 think of the floors kind of pancaking 402 00:16:47,889 --> 00:16:46,159 and then kind of neatly coming down like 403 00:16:49,659 --> 00:16:47,899 like a like a I don't know a like a 404 00:16:52,299 --> 00:16:49,669 house of cards just go and Bam Bam and 405 00:16:53,799 --> 00:16:52,309 then yeah stacking up but you're talking 406 00:16:57,639 --> 00:16:53,809 about the trusses being all just this 407 00:16:59,919 --> 00:16:57,649 mangled mess no not really stacked on 408 00:17:02,469 --> 00:16:59,929 top of each other it depends where you 409 00:17:06,100 --> 00:17:02,479 are in the building um so if you think 410 00:17:09,549 --> 00:17:06,110 about it the collapse did not begin with 411 00:17:11,019 --> 00:17:09,559 the uppermost floors it began at the 412 00:17:14,129 --> 00:17:11,029 floors that were most heavily weakened 413 00:17:16,899 --> 00:17:14,139 by fire which were somewhat lower and 414 00:17:19,629 --> 00:17:16,909 the top of the building sort of came 415 00:17:22,569 --> 00:17:19,639 down with the collapse and then itself 416 00:17:26,740 --> 00:17:22,579 sort of impacted the ground impacted the 417 00:17:28,600 --> 00:17:26,750 rubble below each floor down once the 418 00:17:30,999 --> 00:17:28,610 collapse starts is getting a heavier 419 00:17:34,299 --> 00:17:31,009 impact than the one before so by the 420 00:17:35,980 --> 00:17:34,309 time the second floor collapses it's got 421 00:17:37,990 --> 00:17:35,990 the weight of a hundred floors on its 422 00:17:40,779 --> 00:17:38,000 back that's that's why things were so 423 00:17:43,419 --> 00:17:40,789 badly pulverized because it it's just at 424 00:17:46,629 --> 00:17:43,429 the effect adds up as you come down the 425 00:17:48,360 --> 00:17:46,639 building I did a incredibly crude 426 00:17:51,409 --> 00:17:48,370 calculation on this 427 00:17:55,049 --> 00:17:51,419 just looking at the average floor height 428 00:17:57,269 --> 00:17:55,059 and falling to the ground never minding 429 00:18:00,180 --> 00:17:57,279 the affected fire you know just if you 430 00:18:02,159 --> 00:18:00,190 just had 110 floors at the elevation 431 00:18:05,460 --> 00:18:02,169 there at and you let them fall and that 432 00:18:08,039 --> 00:18:05,470 very crude calculation gave me a kinetic 433 00:18:12,450 --> 00:18:08,049 energy that is about 10% of the 434 00:18:15,390 --> 00:18:12,460 Hiroshima bomb oh yeah so yeah things 435 00:18:17,880 --> 00:18:15,400 got destroyed yeah yeah it's a lot of 436 00:18:19,740 --> 00:18:17,890 energy did you do have similar thoughts 437 00:18:21,330 --> 00:18:19,750 about building seven there was even kind 438 00:18:25,560 --> 00:18:21,340 of in your on your radar in terms of 439 00:18:27,210 --> 00:18:25,570 like you know how is it collapsed yes it 440 00:18:28,889 --> 00:18:27,220 was on my radar because it was a road 441 00:18:31,100 --> 00:18:28,899 block that I had to walk around all the 442 00:18:36,060 --> 00:18:34,139 the thing is I didn't think a great deal 443 00:18:38,940 --> 00:18:36,070 about it because I knew one thing that 444 00:18:41,820 --> 00:18:38,950 had become public knowledge on the 11th 445 00:18:44,430 --> 00:18:41,830 or on the 12th which was that that 446 00:18:48,049 --> 00:18:44,440 building caught fire when North Tower 447 00:18:50,430 --> 00:18:48,059 collapsed when the North Tower collapsed 448 00:18:53,669 --> 00:18:50,440 the fire department was very badly 449 00:18:56,130 --> 00:18:53,679 disorganized a large number large number 450 00:18:58,560 --> 00:18:56,140 of firefighters were dead a large number 451 00:19:00,450 --> 00:18:58,570 of officers were dead as well and the 452 00:19:05,630 --> 00:19:00,460 dust in the air prevented their radios 453 00:19:09,029 --> 00:19:05,640 from working so the fire department 454 00:19:10,799 --> 00:19:09,039 upper-upper officers made the decision 455 00:19:13,440 --> 00:19:10,809 to not attempt to fight the fire in 456 00:19:14,940 --> 00:19:13,450 number seven because they believed that 457 00:19:16,289 --> 00:19:14,950 they would not be able to put it out and 458 00:19:18,029 --> 00:19:16,299 what it would do is get a couple of more 459 00:19:21,600 --> 00:19:18,039 a couple hundred more firefighters 460 00:19:22,919 --> 00:19:21,610 killed for nothing yeah I think it was 461 00:19:24,360 --> 00:19:22,929 the correct decision everyone I've 462 00:19:26,789 --> 00:19:24,370 spoken to thinks it was the correct 463 00:19:30,779 --> 00:19:26,799 decision but what that means is what you 464 00:19:32,490 --> 00:19:30,789 have is an uncontrolled fire in a forty 465 00:19:34,529 --> 00:19:32,500 swiss forty five forty seven storey 466 00:19:38,210 --> 00:19:34,539 building which is not something you see 467 00:19:41,100 --> 00:19:38,220 very often and you took about like 468 00:19:42,539 --> 00:19:41,110 examining they debris pile or like you 469 00:19:43,919 --> 00:19:42,549 should experience of being that by the 470 00:19:46,799 --> 00:19:43,929 debate pylons one thing you mentioned 471 00:19:48,810 --> 00:19:46,809 was the fires and this is another thing 472 00:19:53,760 --> 00:19:48,820 that people gets kind of suspicious 473 00:19:55,710 --> 00:19:53,770 about and you know you talk about how 474 00:19:58,500 --> 00:19:55,720 much how much actually flammable 475 00:20:00,960 --> 00:19:58,510 material there was in the building you 476 00:20:01,919 --> 00:20:00,970 know people say flammable material you 477 00:20:03,690 --> 00:20:01,929 know I'm looking around 478 00:20:05,759 --> 00:20:03,700 office people think flammable material 479 00:20:08,009 --> 00:20:05,769 is paper and books and things like that 480 00:20:13,200 --> 00:20:08,019 the plastic that's used for furniture 481 00:20:15,570 --> 00:20:13,210 will burn carpeting burns um there's a 482 00:20:17,249 --> 00:20:15,580 lot of there's a lot of things that will 483 00:20:19,590 --> 00:20:17,259 burn in an office if you get them hot 484 00:20:22,139 --> 00:20:19,600 enough and most of them are poisonous 485 00:20:23,609 --> 00:20:22,149 when they burn you really don't want to 486 00:20:27,930 --> 00:20:23,619 be around burning plastic if you can 487 00:20:30,690 --> 00:20:27,940 avoid it so when all that stuff gets 488 00:20:32,580 --> 00:20:30,700 trapped in a confined space it's like 489 00:20:35,519 --> 00:20:32,590 you know an underground tire fire it 490 00:20:38,190 --> 00:20:35,529 just there's not enough oxygen for it to 491 00:20:40,409 --> 00:20:38,200 get burned hot and just burn itself out 492 00:20:43,470 --> 00:20:40,419 so it just serves smoulders for a very 493 00:20:45,060 --> 00:20:43,480 long time and it was a couple of months 494 00:20:47,519 --> 00:20:45,070 before the fires were finding me out 495 00:20:50,070 --> 00:20:47,529 because there was all of this flammable 496 00:20:52,859 --> 00:20:50,080 material down in the cellar hole of the 497 00:20:55,379 --> 00:20:52,869 entire complex being fed a little bit of 498 00:20:57,419 --> 00:20:55,389 oxygen so the fire just kept going and 499 00:20:59,730 --> 00:20:57,429 then it would occasionally flare if I 500 00:21:04,440 --> 00:20:59,740 guess when it was exposed to oxygen when 501 00:21:05,970 --> 00:21:04,450 their base Kotik uncovered yes and there 502 00:21:09,899 --> 00:21:05,980 were hoses with the sight to deal with 503 00:21:12,869 --> 00:21:09,909 that right you know a big big like kind 504 00:21:14,960 --> 00:21:12,879 of conspiracy thing there is this they 505 00:21:19,320 --> 00:21:14,970 claimed that there was molten steel 506 00:21:22,830 --> 00:21:19,330 liquid molten steel on the site in the 507 00:21:24,659 --> 00:21:22,840 in the fires did you ever hear of 508 00:21:25,850 --> 00:21:24,669 anything like that or see anything like 509 00:21:29,430 --> 00:21:25,860 that 510 00:21:32,190 --> 00:21:29,440 nope the only place I ever saw anything 511 00:21:34,769 --> 00:21:32,200 looked remotely like that was some of 512 00:21:37,109 --> 00:21:34,779 the video on before the collapses and it 513 00:21:40,019 --> 00:21:37,119 was pretty clear that the that the 514 00:21:43,409 --> 00:21:40,029 molten material was aluminum from the 515 00:21:46,590 --> 00:21:43,419 facade which melts with much lower 516 00:21:48,029 --> 00:21:46,600 temperature than steel I never I never 517 00:21:49,680 --> 00:21:48,039 heard anybody talking about anything 518 00:21:52,230 --> 00:21:49,690 like molten steel on site I never saw 519 00:21:55,080 --> 00:21:52,240 anything I never saw any metal that 520 00:21:56,909 --> 00:21:55,090 showed signs of having melted I saw 521 00:21:58,350 --> 00:21:56,919 metal that was twisted and bent in all 522 00:22:00,749 --> 00:21:58,360 sorts of different shapes but never 523 00:22:03,389 --> 00:22:00,759 anything that could melt to different 524 00:22:05,669 --> 00:22:03,399 appearance yeah and you you've been in 525 00:22:08,460 --> 00:22:05,679 you know all parts of the the site like 526 00:22:09,869 --> 00:22:08,470 I think you you went down a hole in the 527 00:22:12,930 --> 00:22:09,879 street that would have been like kind of 528 00:22:14,550 --> 00:22:12,940 next building seven so you would have 529 00:22:18,780 --> 00:22:14,560 seen basically the 530 00:22:20,790 --> 00:22:18,790 the bottom of the pile as it was well 531 00:22:23,610 --> 00:22:20,800 actually that hole led to a garage that 532 00:22:26,700 --> 00:22:23,620 um the area that we were in was almost 533 00:22:29,190 --> 00:22:26,710 untouched want the the south end of it 534 00:22:32,670 --> 00:22:29,200 was crushed but the port part where we 535 00:22:33,960 --> 00:22:32,680 went down the hole it was on I that was 536 00:22:36,960 --> 00:22:33,970 November already by the time that 537 00:22:38,310 --> 00:22:36,970 happened and it was you know here here's 538 00:22:41,730 --> 00:22:38,320 where people park their cars in the 539 00:22:44,960 --> 00:22:41,740 morning at the of the 11th but no I I 540 00:22:48,660 --> 00:22:44,970 was all over immediately adjacent to 541 00:22:53,370 --> 00:22:48,670 collapsed steel and I never saw anything 542 00:22:56,400 --> 00:22:53,380 like that yeah and you I mean I imagine 543 00:22:59,580 --> 00:22:56,410 you wouldn't have seen things that looks 544 00:23:00,510 --> 00:22:59,590 like like evidence of explosive 545 00:23:03,090 --> 00:23:00,520 something like I feel kind of silly 546 00:23:06,660 --> 00:23:03,100 asking an expert like is this something 547 00:23:09,210 --> 00:23:06,670 that was even on anybody's radar at the 548 00:23:13,230 --> 00:23:09,220 time were they thinking like that that 549 00:23:15,150 --> 00:23:13,240 they would look at evidence well I mean 550 00:23:16,740 --> 00:23:15,160 I think the conspiracy theory starts 551 00:23:17,850 --> 00:23:16,750 pretty quickly I remember hearing people 552 00:23:20,370 --> 00:23:17,860 saying boy that was just like a 553 00:23:23,670 --> 00:23:20,380 controlled demolition while I was still 554 00:23:27,090 --> 00:23:23,680 on site I I don't I would not have 555 00:23:28,710 --> 00:23:27,100 recognized any anything like that I 556 00:23:29,580 --> 00:23:28,720 don't think I I don't think anybody 557 00:23:31,680 --> 00:23:29,590 would have been able to tell the 558 00:23:39,870 --> 00:23:31,690 difference necessarily unless they were 559 00:23:43,710 --> 00:23:39,880 a specialist in bomb explosions you know 560 00:23:45,390 --> 00:23:43,720 it's funny we as one of the people at 561 00:23:48,540 --> 00:23:45,400 the authority time study was worked on 562 00:23:50,310 --> 00:23:48,550 this they got involved later on with a 563 00:23:51,750 --> 00:23:50,320 lot of the litigation work and I wasn't 564 00:23:53,430 --> 00:23:51,760 particularly involved with that but I 565 00:23:55,140 --> 00:23:53,440 had been on site so I was asked to 566 00:23:58,650 --> 00:23:55,150 review certain photographs and certain 567 00:24:01,440 --> 00:23:58,660 videos from my recollection to those 568 00:24:03,690 --> 00:24:01,450 areas and I remember people saying that 569 00:24:05,970 --> 00:24:03,700 the way that you saw debris and smoke 570 00:24:07,980 --> 00:24:05,980 moving outwards during the collapses was 571 00:24:09,900 --> 00:24:07,990 evidence of controlled demolition and 572 00:24:12,630 --> 00:24:09,910 that's what the effect I was talking to 573 00:24:15,030 --> 00:24:12,640 you about before where the air inside 574 00:24:18,480 --> 00:24:15,040 between two floors has nowhere to go but 575 00:24:21,390 --> 00:24:18,490 out radially outwards as the building 576 00:24:23,370 --> 00:24:21,400 pancakes so you know something that was 577 00:24:25,800 --> 00:24:23,380 pointed to his evidence of explosion of 578 00:24:27,390 --> 00:24:25,810 an explosion had a much simpler 579 00:24:29,070 --> 00:24:27,400 explanation 580 00:24:32,190 --> 00:24:29,080 I've seen that before they described it 581 00:24:34,770 --> 00:24:32,200 as a pyroclastic flow because of you get 582 00:24:36,420 --> 00:24:34,780 similar dust clouds and volcanic 583 00:24:38,070 --> 00:24:36,430 explosions and they think there's 584 00:24:40,230 --> 00:24:38,080 somehow indicates that must have been an 585 00:24:41,490 --> 00:24:40,240 explosion but if you look at you know 586 00:24:43,680 --> 00:24:41,500 building collapses 587 00:24:45,630 --> 00:24:43,690 they just collapsed by by you know 588 00:24:47,850 --> 00:24:45,640 without explosives you get this kind of 589 00:24:49,320 --> 00:24:47,860 similar dust cloud or things like rock 590 00:24:51,330 --> 00:24:49,330 falls and things like that you get the 591 00:24:55,080 --> 00:24:51,340 exact same cloud of dust because as you 592 00:24:57,150 --> 00:24:55,090 say is the air being displaced yeah yeah 593 00:25:00,060 --> 00:24:57,160 and another thing that people point to 594 00:25:04,110 --> 00:25:00,070 is the columns that were cut 595 00:25:06,090 --> 00:25:04,120 after the during the cleanup they did a 596 00:25:07,290 --> 00:25:06,100 lot of removal of you know the columns 597 00:25:10,500 --> 00:25:07,300 that were still standing so they had to 598 00:25:13,110 --> 00:25:10,510 cut them and sometimes they they would 599 00:25:14,700 --> 00:25:13,120 cut them at an angle and people claimed 600 00:25:18,240 --> 00:25:14,710 that you would never cut a column as an 601 00:25:20,669 --> 00:25:18,250 angle do you have any thoughts about 602 00:25:23,340 --> 00:25:20,679 here why why the columns were cut at an 603 00:25:27,900 --> 00:25:23,350 angle during cleanup because because of 604 00:25:31,470 --> 00:25:27,910 the pile of debris I want to emphasize 605 00:25:35,310 --> 00:25:31,480 that as of the 11th as of the evening of 606 00:25:37,110 --> 00:25:35,320 the 11th there was nothing left of one 607 00:25:38,220 --> 00:25:37,120 and two that resemble the building in 608 00:25:40,169 --> 00:25:38,230 any way it's not like there was a 609 00:25:42,210 --> 00:25:40,179 building with a big pile of stuff on top 610 00:25:44,940 --> 00:25:42,220 of it there was nothing left that looked 611 00:25:47,040 --> 00:25:44,950 like a building I the description that 612 00:25:51,030 --> 00:25:47,050 I've used for this is pick up sticks it 613 00:25:52,590 --> 00:25:51,040 was just this random distribution of the 614 00:25:55,799 --> 00:25:52,600 columns that had survived some of them 615 00:25:57,419 --> 00:25:55,809 were straight some of them were not and 616 00:26:01,640 --> 00:25:57,429 they were in every pointing in every 617 00:26:03,570 --> 00:26:01,650 possible direction they were cut in 618 00:26:06,120 --> 00:26:03,580 Ankara meter trying to pick up these 619 00:26:08,160 --> 00:26:06,130 pieces of steel that are tangled in with 620 00:26:10,440 --> 00:26:08,170 each other and there are all different 621 00:26:12,330 --> 00:26:10,450 angles and they cut them wherever they 622 00:26:16,169 --> 00:26:12,340 needed to cut them to get a piece free 623 00:26:17,850 --> 00:26:16,179 to move it out all right those if you're 624 00:26:19,740 --> 00:26:17,860 demolishing a building you would never 625 00:26:22,110 --> 00:26:19,750 cut a column in an angle because it's 626 00:26:24,000 --> 00:26:22,120 you're taking a building down and you 627 00:26:26,940 --> 00:26:24,010 want to have things continue to function 628 00:26:28,860 --> 00:26:26,950 as you come down four by four when 629 00:26:32,400 --> 00:26:28,870 you're dealing with a pile of debris 630 00:26:34,200 --> 00:26:32,410 it's a different situation you you you 631 00:26:36,120 --> 00:26:34,210 looked a lot of the other damage to 632 00:26:39,210 --> 00:26:36,130 other buildings like in particular like 633 00:26:40,950 --> 00:26:39,220 one that stands out is 130 Liberty which 634 00:26:42,870 --> 00:26:40,960 had this huge gash 635 00:26:45,150 --> 00:26:42,880 in the front of it with a very large 636 00:26:49,650 --> 00:26:45,160 piece of the the facade I believe at the 637 00:26:51,360 --> 00:26:49,660 South Tower in it yes and that would 638 00:26:54,150 --> 00:26:51,370 play a bit of structural damage to it 639 00:26:57,930 --> 00:26:54,160 was there was there any danger of 640 00:27:01,590 --> 00:26:57,940 collapse do you think from the top that 641 00:27:05,220 --> 00:27:01,600 building was ever in danger the building 642 00:27:08,820 --> 00:27:05,230 is the hole no it wasn't 130 Liberty was 643 00:27:10,470 --> 00:27:08,830 was a structurally anomalous in the 644 00:27:12,840 --> 00:27:10,480 opposite way of the World Trade Center 645 00:27:16,470 --> 00:27:12,850 it was heavier than it needed to be my 646 00:27:20,070 --> 00:27:16,480 understanding had been built by Irving 647 00:27:23,730 --> 00:27:20,080 Trust Bank originally which is long con 648 00:27:27,030 --> 00:27:23,740 now as a place where they would have 649 00:27:28,650 --> 00:27:27,040 trading floors and they didn't know how 650 00:27:30,030 --> 00:27:28,660 many trading floors they would have were 651 00:27:31,320 --> 00:27:30,040 they going to rent out space the people 652 00:27:33,780 --> 00:27:31,330 who would put in trading fours and 653 00:27:36,030 --> 00:27:33,790 trading fours in terms of structural 654 00:27:38,640 --> 00:27:36,040 design are heavier than normal or office 655 00:27:41,010 --> 00:27:38,650 space so what they did was they designed 656 00:27:42,750 --> 00:27:41,020 the whole building for literally twice 657 00:27:44,850 --> 00:27:42,760 to the live load of a normal office 658 00:27:46,680 --> 00:27:44,860 building that gave them maximum 659 00:27:49,560 --> 00:27:46,690 flexibility of what to do with it and it 660 00:27:52,800 --> 00:27:49,570 had a traditional lateral load system it 661 00:27:55,920 --> 00:27:52,810 didn't have a tube system so the having 662 00:27:58,080 --> 00:27:55,930 the gash on the North Face did not 663 00:28:01,890 --> 00:27:58,090 significantly reduce its lateral 664 00:28:05,090 --> 00:28:01,900 stability so the building was dangerous 665 00:28:08,430 --> 00:28:05,100 because every single window was smashed 666 00:28:11,040 --> 00:28:08,440 pieces of the metal facade panels were 667 00:28:13,530 --> 00:28:11,050 loose so it could kill somebody walking 668 00:28:15,450 --> 00:28:13,540 by by just dropping five pounds of 669 00:28:19,200 --> 00:28:15,460 debris onto them yeah but the building 670 00:28:21,870 --> 00:28:19,210 as a whole was not unstable so I guess 671 00:28:24,390 --> 00:28:21,880 we'll trace enter 7 was a similar 672 00:28:26,670 --> 00:28:24,400 distance away from the towers as 130 673 00:28:29,880 --> 00:28:26,680 Liberty not entirely sure but you know 674 00:28:33,030 --> 00:28:29,890 some distance away so it's suffered 675 00:28:34,830 --> 00:28:33,040 similar kinds of damage would there have 676 00:28:37,260 --> 00:28:34,840 been differences in the effects of the 677 00:28:40,790 --> 00:28:37,270 damage on building 7 because of its 678 00:28:43,260 --> 00:28:40,800 different design this is 130 Liberty 679 00:28:45,660 --> 00:28:43,270 Isis I don't know is the fact I suspect 680 00:28:48,690 --> 00:28:45,670 130 Liberty was a stronger building than 681 00:28:51,720 --> 00:28:48,700 7 the biggest difference between them is 682 00:28:54,120 --> 00:28:51,730 as far as I know there was not there was 683 00:28:54,690 --> 00:28:54,130 very little fire spread in 130 Liberty 684 00:28:57,119 --> 00:28:54,700 on it 685 00:29:02,460 --> 00:28:57,129 the debris that's hid it wasn't on fire 686 00:29:04,379 --> 00:29:02,470 and for example at 7:00 the fires at the 687 00:29:06,269 --> 00:29:04,389 top floors were rather small and 688 00:29:08,070 --> 00:29:06,279 basically extinguished themselves 689 00:29:10,889 --> 00:29:08,080 because they didn't spread so they ran 690 00:29:12,989 --> 00:29:10,899 out of fuel so fires the lower floors 691 00:29:14,879 --> 00:29:12,999 that spread so there may have been some 692 00:29:18,810 --> 00:29:14,889 small fires at 1:30 Liberty but they 693 00:29:20,129 --> 00:29:18,820 didn't continue to burn yeah that's the 694 00:29:22,430 --> 00:29:20,139 big difference I believe between the two 695 00:29:24,749 --> 00:29:22,440 yeah definitely well yeah you could see 696 00:29:28,499 --> 00:29:24,759 huge amounts of fire in World Trade 697 00:29:31,229 --> 00:29:28,509 Center seven yeah another building is 698 00:29:33,330 --> 00:29:31,239 one Liberty Plaza and it was interesting 699 00:29:35,460 --> 00:29:33,340 you wrote about this in the book is that 700 00:29:37,859 --> 00:29:35,470 there were a lot of rumors going around 701 00:29:40,499 --> 00:29:37,869 that one Liberty Plaza was going to 702 00:29:43,859 --> 00:29:40,509 collapse and you went and looked at it 703 00:29:46,950 --> 00:29:43,869 and you saw that it wasn't and then you 704 00:29:52,529 --> 00:29:46,960 kind of tried to tamp down the rumors by 705 00:29:54,899 --> 00:29:52,539 spreading what you called yeah that was 706 00:29:59,729 --> 00:29:54,909 spreading the counter rumor was probably 707 00:30:04,710 --> 00:29:59,739 me being at that time sort of on edge 708 00:30:06,539 --> 00:30:04,720 and and very tired there's an optical 709 00:30:08,190 --> 00:30:06,549 illusion that anybody can perform with 710 00:30:10,229 --> 00:30:08,200 you need a building about ten stories or 711 00:30:12,419 --> 00:30:10,239 more at all and what you do is you walk 712 00:30:14,820 --> 00:30:12,429 right up to the building get your belly 713 00:30:16,109 --> 00:30:14,830 touching it and look up and if you do 714 00:30:17,970 --> 00:30:16,119 that it looks like the building is 715 00:30:19,379 --> 00:30:17,980 leaning over you hmm 716 00:30:23,399 --> 00:30:19,389 something to do with the way our eyes 717 00:30:27,570 --> 00:30:23,409 and brain function and people were very 718 00:30:28,830 --> 00:30:27,580 on edge I think in part because of seven 719 00:30:31,889 --> 00:30:28,840 World Trade Center more than the other 720 00:30:35,279 --> 00:30:31,899 two because seven were given the 721 00:30:37,799 --> 00:30:35,289 expensive plane damage it was shocking 722 00:30:41,159 --> 00:30:37,809 but not exactly unexpected that one and 723 00:30:43,769 --> 00:30:41,169 two would collapse seven didn't have 724 00:30:45,749 --> 00:30:43,779 that and it was I think it was served in 725 00:30:49,109 --> 00:30:45,759 people's heads here's the building that 726 00:30:51,060 --> 00:30:49,119 didn't look so bad in a collapsed so 727 00:30:55,200 --> 00:30:51,070 every little thing got every little 728 00:30:56,879 --> 00:30:55,210 thing got followed up and I think people 729 00:31:00,090 --> 00:30:56,889 from Thornton time the city went up to 730 00:31:02,239 --> 00:31:00,100 the top of this using spares of one 731 00:31:04,769 --> 00:31:02,249 Liberty I don't know four or five times 732 00:31:07,440 --> 00:31:04,779 looking for damage because somebody said 733 00:31:08,840 --> 00:31:07,450 you know it doesn't look right and there 734 00:31:11,640 --> 00:31:08,850 was nothing wrong with the 735 00:31:15,240 --> 00:31:11,650 literally nothing wrong yeah 736 00:31:17,549 --> 00:31:15,250 so you know it was its to me evidence 737 00:31:22,260 --> 00:31:17,559 that even people who deal with the stuff 738 00:31:24,299 --> 00:31:22,270 for a living get spooked and they you 739 00:31:24,899 --> 00:31:24,309 know you see a pattern even when it's 740 00:31:26,700 --> 00:31:24,909 not there 741 00:31:27,930 --> 00:31:26,710 so the pattern was the building was near 742 00:31:30,180 --> 00:31:27,940 the site it's a tall building a 743 00:31:32,760 --> 00:31:30,190 collapsed maybe one Liberty's gonna 744 00:31:35,450 --> 00:31:32,770 collect collapse next yes only I mean 745 00:31:37,649 --> 00:31:35,460 yeah it's like all bets are off for 746 00:31:39,120 --> 00:31:37,659 after you've seen what you've seen that 747 00:31:40,460 --> 00:31:39,130 day because it's something no one's 748 00:31:44,630 --> 00:31:40,470 experienced before 749 00:31:47,010 --> 00:31:44,640 you know much in your mind it goes wild 750 00:31:49,830 --> 00:31:47,020 let's let's talk a little bit about the 751 00:31:51,690 --> 00:31:49,840 yeah I sent you the the whole C report 752 00:31:54,840 --> 00:31:51,700 which is this report done by the 753 00:31:56,520 --> 00:31:54,850 University of Alaska and I kind of yeah 754 00:31:59,520 --> 00:31:56,530 I ask you for your your general 755 00:32:01,560 --> 00:31:59,530 impression of it how do you kind of 756 00:32:05,730 --> 00:32:01,570 characterize like what you've what 757 00:32:07,529 --> 00:32:05,740 you've seen a bit so far well I didn't 758 00:32:11,730 --> 00:32:07,539 find it very convincing as I guess the 759 00:32:13,740 --> 00:32:11,740 the best way to put it I feel like they 760 00:32:17,370 --> 00:32:13,750 made a bunch of assumptions some of 761 00:32:20,370 --> 00:32:17,380 which are not very well thought out they 762 00:32:22,620 --> 00:32:20,380 begin by saying that you know they're 763 00:32:25,799 --> 00:32:22,630 not sure about the expenses of the of 764 00:32:27,600 --> 00:32:25,809 the temperatures that were inside again 765 00:32:30,450 --> 00:32:27,610 this is a building that was on fire with 766 00:32:33,299 --> 00:32:30,460 no real attempt to put out the fire 767 00:32:36,169 --> 00:32:33,309 no no attempt to fight it no sign that 768 00:32:39,240 --> 00:32:36,179 the sprinklers functioned properly 769 00:32:40,799 --> 00:32:39,250 fires get extremely hot it's the reason 770 00:32:44,010 --> 00:32:40,809 that you know you taught to stay at the 771 00:32:47,159 --> 00:32:44,020 floor the fire at the ceiling in an in a 772 00:32:49,590 --> 00:32:47,169 in a case like this is going to be 773 00:32:53,130 --> 00:32:49,600 somewhere above 2,000 degrees Fahrenheit 774 00:32:56,190 --> 00:32:53,140 and that is enough to basically destroy 775 00:32:59,430 --> 00:32:56,200 structure it doesn't melt this deal it 776 00:33:02,100 --> 00:32:59,440 weakens it and when this deal is weak it 777 00:33:04,409 --> 00:33:02,110 will start to collapse and in that 778 00:33:07,470 --> 00:33:04,419 report they extensively modeled the 779 00:33:12,120 --> 00:33:07,480 building but they're assuming that all 780 00:33:14,490 --> 00:33:12,130 the members are present and if fires a 781 00:33:17,220 --> 00:33:14,500 couple of floors away from the area 782 00:33:18,750 --> 00:33:17,230 they're looking had weakened beams that 783 00:33:20,430 --> 00:33:18,760 are bracing columns then the frame 784 00:33:23,490 --> 00:33:20,440 wouldn't function the way that their 785 00:33:28,020 --> 00:33:23,500 model assumes functions 786 00:33:30,000 --> 00:33:28,030 so I I just they did not seem to take 787 00:33:31,770 --> 00:33:30,010 this into account and maybe they did and 788 00:33:35,370 --> 00:33:31,780 it's not written up very well I can't I 789 00:33:36,690 --> 00:33:35,380 can't say for certain but any time I see 790 00:33:39,380 --> 00:33:36,700 that they're modeling the whole frame 791 00:33:41,850 --> 00:33:39,390 but they're only talking about the 792 00:33:44,520 --> 00:33:41,860 effective temperature at the specific 793 00:33:47,150 --> 00:33:44,530 column they're looking at I'm not so 794 00:33:49,860 --> 00:33:47,160 sure I that that makes much sense yeah 795 00:33:51,870 --> 00:33:49,870 yeah definitely I think they they didn't 796 00:33:53,550 --> 00:33:51,880 really account for that and when they 797 00:33:55,800 --> 00:33:53,560 were doing simulations it seemed like 798 00:33:58,320 --> 00:33:55,810 they were just simply removing a section 799 00:34:02,940 --> 00:33:58,330 of a column and leaving the rest of the 800 00:34:05,490 --> 00:34:02,950 building untouched that method has 801 00:34:07,890 --> 00:34:05,500 actually has a long history to it that 802 00:34:10,950 --> 00:34:07,900 method has been used in other countries 803 00:34:14,880 --> 00:34:10,960 and particularly in the UK as a form of 804 00:34:17,220 --> 00:34:14,890 modeling for bomb blasts at least the 805 00:34:18,690 --> 00:34:17,230 80s and maybe earlier than that and it's 806 00:34:20,820 --> 00:34:18,700 actually in the New York City Building 807 00:34:22,980 --> 00:34:20,830 Code now in terms of resilience as one 808 00:34:24,630 --> 00:34:22,990 of the methods to check on the 809 00:34:27,840 --> 00:34:24,640 building's resilience is to remove key 810 00:34:29,700 --> 00:34:27,850 members so that method makes sense but 811 00:34:32,700 --> 00:34:29,710 it's not a model of a specific event 812 00:34:34,320 --> 00:34:32,710 that you're trying to recreate yeah it 813 00:34:37,580 --> 00:34:34,330 would make sense if you were modeling a 814 00:34:41,430 --> 00:34:37,590 bomb like the 1993 World Trade Center 815 00:34:42,900 --> 00:34:41,440 attacks yes well just a bomb of one 816 00:34:44,940 --> 00:34:42,910 column even then I suppose there would 817 00:34:47,880 --> 00:34:44,950 have been a lot of force blast force on 818 00:34:50,430 --> 00:34:47,890 the floors and beams around the column 819 00:34:51,870 --> 00:34:50,440 as well so it's still not getting in any 820 00:34:54,300 --> 00:34:51,880 tally accurate thing but it gives you a 821 00:34:58,110 --> 00:34:54,310 baseline of you know if this column is 822 00:35:01,440 --> 00:34:58,120 taken out what will happen but but not 823 00:35:04,470 --> 00:35:01,450 entirely accurate did you look at the 824 00:35:08,820 --> 00:35:04,480 the video I made kind of like looking 825 00:35:11,310 --> 00:35:08,830 into the static versus dynamic modeling 826 00:35:14,730 --> 00:35:11,320 that they did no I did not another 827 00:35:17,580 --> 00:35:14,740 factor that yeah no it's just that it 828 00:35:20,760 --> 00:35:17,590 seems like they they modeled it using a 829 00:35:22,320 --> 00:35:20,770 using static analysis and correct me if 830 00:35:26,580 --> 00:35:22,330 I'm wrong with a static analysis would 831 00:35:28,530 --> 00:35:26,590 be where you're just measuring kind of 832 00:35:31,380 --> 00:35:28,540 the defamation of a building under a 833 00:35:34,680 --> 00:35:31,390 load like you how much the the members 834 00:35:36,120 --> 00:35:34,690 will will deflect and it's not really 835 00:35:40,140 --> 00:35:36,130 your something you would do for 836 00:35:43,170 --> 00:35:40,150 an actual in process collapse it can be 837 00:35:46,140 --> 00:35:43,180 part of that analysis but yeah you're 838 00:35:50,460 --> 00:35:46,150 correct that it's not sufficient for up 839 00:35:52,680 --> 00:35:50,470 until the 1960s tall building design was 840 00:35:54,809 --> 00:35:52,690 typically done only statically mm-hmm 841 00:35:58,319 --> 00:35:54,819 because it's a great deal of computation 842 00:35:59,999 --> 00:35:58,329 to do dynamic analysis tall buildings 843 00:36:03,359 --> 00:36:00,009 and particularly slender tall buildings 844 00:36:06,420 --> 00:36:03,369 now regularly get dynamic analysis as 845 00:36:08,579 --> 00:36:06,430 per their original design I suspect 846 00:36:11,160 --> 00:36:08,589 there was some dynamic analysis at the 847 00:36:14,160 --> 00:36:11,170 World Trade Center but I don't know I've 848 00:36:17,299 --> 00:36:14,170 read various interviews with Wes 849 00:36:20,190 --> 00:36:17,309 Robertson took place after the 11th and 850 00:36:23,309 --> 00:36:20,200 it seems that it was a very thorough 851 00:36:27,539 --> 00:36:23,319 design they did not make any decisions 852 00:36:29,870 --> 00:36:27,549 lightly but you can do you can do a lot 853 00:36:32,729 --> 00:36:29,880 with spec analysis but it has its limits 854 00:36:34,920 --> 00:36:32,739 yeah they they push the static analysis 855 00:36:37,049 --> 00:36:34,930 to the extent that they show the 856 00:36:40,769 --> 00:36:37,059 building tipping over and it's at about 857 00:36:44,069 --> 00:36:40,779 30 40 degrees and it seems like that's 858 00:36:46,079 --> 00:36:44,079 kind of to me like an inappropriate use 859 00:36:48,299 --> 00:36:46,089 of static analysis because the building 860 00:36:52,170 --> 00:36:48,309 is actually moving at that point if a 861 00:36:55,469 --> 00:36:52,180 building is tipped over 40 degrees then 862 00:36:58,670 --> 00:36:55,479 you can you still say that static 863 00:37:01,469 --> 00:36:58,680 analysis is valid for those situation 864 00:37:03,239 --> 00:37:01,479 well I don't think it's a realistic 865 00:37:05,190 --> 00:37:03,249 model if you tip one of these buildings 866 00:37:08,849 --> 00:37:05,200 40 degrees you're gonna have all sorts 867 00:37:11,910 --> 00:37:08,859 of secondary effects that are not part 868 00:37:13,950 --> 00:37:11,920 of a normal static analysis I mean if a 869 00:37:17,729 --> 00:37:13,960 building is tipping over like that then 870 00:37:19,680 --> 00:37:17,739 gravity load is causing bending in the 871 00:37:22,079 --> 00:37:19,690 building in a way that it doesn't when 872 00:37:23,219 --> 00:37:22,089 the building is vertical I don't know 873 00:37:24,870 --> 00:37:23,229 how you're going to take that into 874 00:37:27,120 --> 00:37:24,880 account in a static analysis unless you 875 00:37:30,690 --> 00:37:27,130 do a series of such analyses at sort of 876 00:37:33,120 --> 00:37:30,700 every angle of tilt which seems to not 877 00:37:34,589 --> 00:37:33,130 be what they did yeah I mean static 878 00:37:39,120 --> 00:37:34,599 analysis kind of ignores the time 879 00:37:41,130 --> 00:37:39,130 component yes and impact yeah yeah so 880 00:37:43,950 --> 00:37:41,140 let the momentum of things and things 881 00:37:45,089 --> 00:37:43,960 hitting other things and you know the 882 00:37:47,219 --> 00:37:45,099 building starts to tip it's going to 883 00:37:48,700 --> 00:37:47,229 continue to tip it's not just a static 884 00:37:50,560 --> 00:37:48,710 force 885 00:37:52,930 --> 00:37:50,570 I think that they did they try to 886 00:37:55,780 --> 00:37:52,940 replicate NIST's analysis and they did 887 00:37:57,490 --> 00:37:55,790 it by removing a line of three columns 888 00:38:00,520 --> 00:37:57,500 and then removing another set of three 889 00:38:02,740 --> 00:38:00,530 columns and then things started to fail 890 00:38:03,880 --> 00:38:02,750 progressively like all the columns the 891 00:38:06,670 --> 00:38:03,890 loads were transferred to the other 892 00:38:09,760 --> 00:38:06,680 columns and they failed but they kind of 893 00:38:11,980 --> 00:38:09,770 used this to make it seem like the the 894 00:38:13,720 --> 00:38:11,990 building would actually tip over and I 895 00:38:16,660 --> 00:38:13,730 think to do that they would have to know 896 00:38:18,850 --> 00:38:16,670 at what time the columns failed because 897 00:38:20,830 --> 00:38:18,860 if they all failed within half a second 898 00:38:22,120 --> 00:38:20,840 or within two or three seconds the 899 00:38:24,790 --> 00:38:22,130 building wouldn't actually have the time 900 00:38:28,210 --> 00:38:24,800 to tip over so you couldn't really say 901 00:38:29,890 --> 00:38:28,220 it had tipped over but I think there's a 902 00:38:32,470 --> 00:38:29,900 lot of questions around around their 903 00:38:35,860 --> 00:38:32,480 report and that type of thing a quick 904 00:38:37,750 --> 00:38:35,870 question like in professor holsters 905 00:38:41,860 --> 00:38:37,760 presentation that he gave he mentioned 906 00:38:46,210 --> 00:38:41,870 that the the building had been evacuated 907 00:38:47,950 --> 00:38:46,220 and there wouldn't be a live load of the 908 00:38:52,240 --> 00:38:47,960 people within the building 909 00:38:54,640 --> 00:38:52,250 and that would make a difference to the 910 00:38:55,750 --> 00:38:54,650 calculations do you think that would 911 00:38:57,670 --> 00:38:55,760 actually make a significant difference 912 00:39:01,930 --> 00:38:57,680 the people being evacuated out of the 913 00:39:06,400 --> 00:39:01,940 building normal office space people are 914 00:39:09,880 --> 00:39:06,410 a real but part of the load but well 915 00:39:14,080 --> 00:39:09,890 under half normal office space furniture 916 00:39:18,550 --> 00:39:14,090 and papers and contents weighs more than 917 00:39:19,840 --> 00:39:18,560 people yeah so I you know yes the 918 00:39:21,430 --> 00:39:19,850 building was somewhat lighter because 919 00:39:24,850 --> 00:39:21,440 the loads were somewhat lighter because 920 00:39:27,400 --> 00:39:24,860 of that yes it's getting into the 921 00:39:30,370 --> 00:39:27,410 details of the analysis and and I'm not 922 00:39:32,940 --> 00:39:30,380 sure either he knows or that I know 923 00:39:36,520 --> 00:39:32,950 exactly what this did in their analysis 924 00:39:39,100 --> 00:39:36,530 yeah yeah I don't think I don't remember 925 00:39:41,260 --> 00:39:39,110 the live load being mentioned in in this 926 00:39:42,850 --> 00:39:41,270 analysis no it's not just the people 927 00:39:46,090 --> 00:39:42,860 it's the floors themselves which are the 928 00:39:47,500 --> 00:39:46,100 the mass of the building but they're not 929 00:39:51,390 --> 00:39:47,510 they're not live load they're just 930 00:39:55,960 --> 00:39:51,400 they're dead load but they're not yeah 931 00:40:00,870 --> 00:39:55,970 so you know a general thing kind of 932 00:40:03,309 --> 00:40:00,880 closing up here like it's it's very hard 933 00:40:05,589 --> 00:40:03,319 to get people to talk about this type of 934 00:40:06,880 --> 00:40:05,599 thing your you're an engineer you're an 935 00:40:09,490 --> 00:40:06,890 expert on it and this this type of 936 00:40:10,599 --> 00:40:09,500 things and you you were on the site so 937 00:40:13,289 --> 00:40:10,609 it's great you have this really great 938 00:40:16,480 --> 00:40:13,299 perspective I but I find it very hard to 939 00:40:20,260 --> 00:40:16,490 get people like engineers or scientists 940 00:40:23,289 --> 00:40:20,270 to talk about conspiracy theories what's 941 00:40:25,720 --> 00:40:23,299 what's your sense about how 9/11 942 00:40:30,849 --> 00:40:25,730 conspiracy theories are viewed within 943 00:40:33,430 --> 00:40:30,859 the engineering community I've never met 944 00:40:34,870 --> 00:40:33,440 a structural engineer of a practicing 945 00:40:36,549 --> 00:40:34,880 structural engineer who believes them 946 00:40:39,579 --> 00:40:36,559 that doesn't mean that those such people 947 00:40:43,210 --> 00:40:39,589 don't exist I'm sure they do but you 948 00:40:45,039 --> 00:40:43,220 would think that if there was something 949 00:40:47,079 --> 00:40:45,049 funny about what happened here that 950 00:40:51,309 --> 00:40:47,089 engineers in New York would be aware of 951 00:40:54,670 --> 00:40:51,319 it and there's really no sign that 952 00:40:57,760 --> 00:40:54,680 anybody here believes believes that kind 953 00:41:02,770 --> 00:40:57,770 of theory it is sort of fascinating to 954 00:41:05,559 --> 00:41:02,780 me that so much of the the conspiracy 955 00:41:10,089 --> 00:41:05,569 theory comes from people who are quite 956 00:41:12,490 --> 00:41:10,099 far away and not necessarily spend a lot 957 00:41:14,170 --> 00:41:12,500 of time dealing with with tall buildings 958 00:41:16,480 --> 00:41:14,180 and don't miss an actual call though 959 00:41:17,829 --> 00:41:16,490 because about this theory and don't 960 00:41:21,250 --> 00:41:17,839 necessarily spend a lot of time dealing 961 00:41:25,539 --> 00:41:21,260 with tall buildings that have real-life 962 00:41:27,460 --> 00:41:25,549 problems for example the World Trade 963 00:41:31,870 --> 00:41:27,470 Center was built with asbestos 964 00:41:35,039 --> 00:41:31,880 fireproofing and not not number seven 965 00:41:37,359 --> 00:41:35,049 numbers one and two and that was 966 00:41:39,880 --> 00:41:37,369 outlawed not very long after the 967 00:41:41,260 --> 00:41:39,890 buildings were completed and the way 968 00:41:43,059 --> 00:41:41,270 that the Port Authority which owned the 969 00:41:44,890 --> 00:41:43,069 buildings was dealing with it was when a 970 00:41:47,109 --> 00:41:44,900 floor came empty they stripped it out 971 00:41:49,359 --> 00:41:47,119 and it was considered to be you know 972 00:41:50,920 --> 00:41:49,369 it's it's not people are not being 973 00:41:54,069 --> 00:41:50,930 exposed if it's hidden in the ceiling 974 00:41:55,870 --> 00:41:54,079 space but anytime there was going to be 975 00:42:00,730 --> 00:41:55,880 demolition work then the whole floor was 976 00:42:03,640 --> 00:42:00,740 was was abated and the new fire proofing 977 00:42:06,730 --> 00:42:03,650 that was used in the late 70s and the 978 00:42:11,980 --> 00:42:06,740 80s turns out had a problem with 979 00:42:12,500 --> 00:42:11,990 adhering to steel so they had the 980 00:42:14,510 --> 00:42:12,510 asbestos 981 00:42:18,440 --> 00:42:14,520 may have been pretty close to 100% gone 982 00:42:22,670 --> 00:42:18,450 by 2001 but there were a number of 983 00:42:25,300 --> 00:42:22,680 floors that had fire proofing that 984 00:42:27,320 --> 00:42:25,310 worked great if everything was static 985 00:42:29,210 --> 00:42:27,330 but of course the impact of the 986 00:42:31,000 --> 00:42:29,220 building's caused the impact of the 987 00:42:33,650 --> 00:42:31,010 airplanes cause both buildings to move 988 00:42:35,450 --> 00:42:33,660 much more than normal movement and it 989 00:42:40,220 --> 00:42:35,460 came suddenly it's not like a wind 990 00:42:42,620 --> 00:42:40,230 builds up it was a sharp impact and it's 991 00:42:44,660 --> 00:42:42,630 quite likely that a lot of fire proofing 992 00:42:48,470 --> 00:42:44,670 simply fell off of the floor trusses 993 00:42:51,410 --> 00:42:48,480 when that happened which is something 994 00:42:52,850 --> 00:42:51,420 that you know this problem is known no 995 00:42:55,100 --> 00:42:52,860 way to ever know the extent of what 996 00:42:56,390 --> 00:42:55,110 actually happened right yeah somebody 997 00:42:58,250 --> 00:42:56,400 would have to inspect the building in 998 00:42:59,960 --> 00:42:58,260 between the impact and the collapse know 999 00:43:03,770 --> 00:42:59,970 exactly what happened 1000 00:43:05,600 --> 00:43:03,780 so the ability of the buildings to 1001 00:43:09,380 --> 00:43:05,610 withstand fire may have been 1002 00:43:13,550 --> 00:43:09,390 significantly reduced but we don't know 1003 00:43:15,080 --> 00:43:13,560 how much and when people say oh how 1004 00:43:19,550 --> 00:43:15,090 could this happen well this is a 1005 00:43:22,250 --> 00:43:19,560 real-life kind of problem in a computer 1006 00:43:24,680 --> 00:43:22,260 frame analysis you say okay the 1007 00:43:26,210 --> 00:43:24,690 temperature is this you know it's going 1008 00:43:28,490 --> 00:43:26,220 to temperature curve is going to look 1009 00:43:29,600 --> 00:43:28,500 like this is the steel heats up but 1010 00:43:34,150 --> 00:43:29,610 maybe that's not accurate 1011 00:43:36,740 --> 00:43:34,160 and it doesn't take that much 1012 00:43:38,470 --> 00:43:36,750 unprotected steel failing in the fire to 1013 00:43:41,000 --> 00:43:38,480 cause a failure in a building like this 1014 00:43:43,310 --> 00:43:41,010 because again all the lateral resistance 1015 00:43:47,870 --> 00:43:43,320 was in the perimeter and the floors were 1016 00:43:51,610 --> 00:43:47,880 lightweight trusses so you could easily 1017 00:43:56,720 --> 00:43:51,620 have a sort of a combination of effects 1018 00:43:58,190 --> 00:43:56,730 not foreseen conspiracy theories had to 1019 00:44:01,040 --> 00:43:58,200 happen because something happens that 1020 00:44:03,550 --> 00:44:01,050 people don't expect and they don't they 1021 00:44:05,720 --> 00:44:03,560 don't they don't want to accept that 1022 00:44:08,390 --> 00:44:05,730 something could happen that no one 1023 00:44:10,820 --> 00:44:08,400 predicted I don't know again the 1024 00:44:11,930 --> 00:44:10,830 engineers I know not a single one of us 1025 00:44:16,790 --> 00:44:11,940 said that these buildings we're going to 1026 00:44:20,150 --> 00:44:16,800 pancake but in retrospect it's not very 1027 00:44:21,920 --> 00:44:20,160 surprising so people don't like that 1028 00:44:24,700 --> 00:44:21,930 combination something that's unexpected 1029 00:44:27,160 --> 00:44:24,710 and horrible yeah 1030 00:44:30,549 --> 00:44:27,170 do you do you ever meet conspiracy 1031 00:44:32,530 --> 00:44:30,559 theorists like in real life and yeah 1032 00:44:35,170 --> 00:44:32,540 have to explain things stuff in person 1033 00:44:37,240 --> 00:44:35,180 though in person though I have 1034 00:44:39,549 --> 00:44:37,250 occasionally come across them online and 1035 00:44:41,890 --> 00:44:39,559 I simply walk away alright I'm not 1036 00:44:45,609 --> 00:44:41,900 interested in it what i always recommend 1037 00:44:47,380 --> 00:44:45,619 it had friends say you know i this guy 1038 00:44:48,490 --> 00:44:47,390 is talking telling me this about the 1039 00:44:50,650 --> 00:44:48,500 World Trade Center what should I tell 1040 00:44:53,170 --> 00:44:50,660 him and actually one of the best 1041 00:44:54,819 --> 00:44:53,180 debunking zuv the conspiracy theory was 1042 00:44:58,930 --> 00:44:54,829 from Popular Mechanics they put out a 1043 00:45:00,760 --> 00:44:58,940 very nice little book explaining why all 1044 00:45:03,059 --> 00:45:00,770 of the common conspiracy theories were 1045 00:45:05,920 --> 00:45:03,069 wrong and I recommend that to people 1046 00:45:07,990 --> 00:45:05,930 yeah yeah me too it's a good book 1047 00:45:10,569 --> 00:45:08,000 although of course they've got excuses 1048 00:45:14,260 --> 00:45:10,579 around that now so it just keeps going 1049 00:45:15,970 --> 00:45:14,270 on yeah yeah all right well I want to 1050 00:45:17,500 --> 00:45:15,980 thank you very much for for talking to 1051 00:45:19,140 --> 00:45:17,510 me I mean a year you say like you you 1052 00:45:22,030 --> 00:45:19,150 wouldn't talk to conspiracy theorists 1053 00:45:23,950 --> 00:45:22,040 but you know this this topic I think you 1054 00:45:26,200 --> 00:45:23,960 know I really appreciate getting your 1055 00:45:29,470 --> 00:45:26,210 perspective on it and I wish I could get 1056 00:45:31,359 --> 00:45:29,480 more engineers to kind of weigh in on 1057 00:45:32,890 --> 00:45:31,369 what they think about the whole whole 1058 00:45:34,420 --> 00:45:32,900 topic even if it's just to say that they 1059 00:45:35,829 --> 00:45:34,430 think it's ridiculous because I think 1060 00:45:38,049 --> 00:45:35,839 there's this idea that all these 1061 00:45:39,670 --> 00:45:38,059 engineers are cowering in the wings 1062 00:45:41,650 --> 00:45:39,680 because they don't want to talk about it 1063 00:45:43,120 --> 00:45:41,660 because it's too scary well I think 1064 00:45:44,710 --> 00:45:43,130 really is more like they don't want to 1065 00:45:47,740 --> 00:45:44,720 talk about it cuz it's it's because it's 1066 00:45:50,829 --> 00:45:47,750 so ridiculous I think that's more likely 1067 00:45:53,770 --> 00:45:50,839 yeah yeah all right well that's that's 1068 00:45:55,270 --> 00:45:53,780 great that was very very interesting do 1069 00:45:56,170 --> 00:45:55,280 you have any anything you want to add 1070 00:46:04,839 --> 00:45:56,180 any final words 1071 00:46:06,640 --> 00:46:04,849 oh you know I building code bodies the 1072 00:46:08,140 --> 00:46:06,650 IB the ICC which Rights the 1073 00:46:10,620 --> 00:46:08,150 International Building Code which is the 1074 00:46:13,210 --> 00:46:10,630 base building code for the whole country 1075 00:46:15,270 --> 00:46:13,220 the committee's here in New York that 1076 00:46:17,799 --> 00:46:15,280 write to New York version of the IBC 1077 00:46:22,329 --> 00:46:17,809 really has taken this stuff into account 1078 00:46:25,089 --> 00:46:22,339 over the last 18 years and it's sort of 1079 00:46:27,849 --> 00:46:25,099 it's frustrating that the engineering 1080 00:46:32,289 --> 00:46:27,859 community is trying to learn from what 1081 00:46:34,420 --> 00:46:32,299 failed and there are people you know the 1082 00:46:35,859 --> 00:46:34,430 conspiracy theorists who are basically 1083 00:46:37,780 --> 00:46:35,869 saying well that lesson doesn't mean 1084 00:46:38,380 --> 00:46:37,790 anything because that's not what 1085 00:46:41,440 --> 00:46:38,390 happened 1086 00:46:44,440 --> 00:46:41,450 and your engineering advances by 1087 00:46:46,210 --> 00:46:44,450 studying failure but that's that's been 1088 00:46:48,370 --> 00:46:46,220 true since structural engineering has 1089 00:46:51,280 --> 00:46:48,380 existed you look at what went wrong last 1090 00:46:54,010 --> 00:46:51,290 time and you try to improve on it that's 1091 00:46:56,560 --> 00:46:54,020 what engineers are doing right now yeah 1092 00:47:00,790 --> 00:46:56,570 and the you know basing it on the 1093 00:47:04,840 --> 00:47:00,800 reality of the situation rather than the 1094 00:47:07,760 --> 00:47:04,850 conspiracy theories all right yeah well