As a builder for the last 45 years, my strongest hunch is that this building will have to come down. I can’t see this thing magically correcting itself one day.

@HyenaBlank

10 ай бұрын

The only way I could imagine it staying is very carefully dismantling the top half so it's smaller, then that lean won't be anywhere near as potentially disastrous.

@kireland8

9 ай бұрын

Absolutely right. I know that building well. It going to be a massive, tricky demolition.

A positive feedback loop for a sinking foundation…nothing to see here people…everything is fine.

@paulonorato7501

2 жыл бұрын

Just like the titanic. Telling folks go back to your rooms everything is fine. Till it was too late for most. I say abandon this sinking titanic before you go down with this building into a pile of rubble.

@slome815

2 жыл бұрын

@@paulonorato7501 That's something that didn't really happen during the sinking though, except during the very first moments after the collision, when the damage was still being inspected. Very few people were trapped inside, mainly because the Titanic never capsized or even had a significant tilt. Just about everyone was up on deck when the ship sank. The order to abandon ship was also given very early, the loading of the first lifeboat started 20 minutes after the collision, the Titanic sunk more then 2 hours later.

I have no reason to care about structural engineering, but good teachers draw students in by their passion, their insight, and clear transfer of understanding. I look forward to these and feel my life enriched by them. Thank you.

@alitlweird

2 жыл бұрын

You _SHOULD_ care about structural engineering.

@JosephKulik2016

2 жыл бұрын

@@alitlweird Touche !!!

@jimjamess8633

2 жыл бұрын

Truer words were never spoken! ( hope I spelled that correctly)!

@BrownEyePinch

2 жыл бұрын

Ummm structural engineering is more important then Art Teacher Architects. You're a fool

One more aspect. If post earthquake liquefaction takes place on the non-bedrock cornet of the building, rapid tipping recovery may take place. There should be a Plan B ready to halt settling in the opposite corner of the building. There’s nothing simple about this problem.

@larrybe2900

2 жыл бұрын

Gravity is simple, just man makes it difficult.

@channelsixtynine069

Жыл бұрын

If liquefaction takes place around that building ...... RUN !

I have been following this situation for some time now. I first heard about the building when there was a report on 60 Minutes. Once I took an effort to learn more about the building and soils conditions, I realized many of the reports, if not all reports, have left out many details at the site that were important factors affecting foundation performance. First of all, the depth and thickness of the Coma sand was not uniform across the footprint of the building. The original foundation design was made assuming that the foundation piles would develop end bearing capacity for the piles with tips in the Coma sand layer. This was the main cause of the uneven settlement and tipping of the building. A second factor affecting the tipping of the building was construction of the transit center across the street after the construction of the foundation. The construction of the transit center included the construction of a massive, stiff earth retaining structure along the side bordering the Millennium Tower and other buildings. This was combined with a local dewatering of the worksite that lowered the elevation of the water table by at least 85 feet, the depth of the excavation for construction of the transit center. The presence of the earth retaining structure created a constraint against soil displacements in the direction of the transit center caused by the settlement of the Millennium Tower. The lowering of the water table could have caused consolidation of the softer layers of soil near the excavation for the transit center. I believe both of these last two factors were created after the foundation of the Millennium Tower were constructed and could not be anticipated by the foundation designers. Another problem is the basic approach taken for the foundation repair. If one considers what was done in Italy for the Leaning Tower of Pisa, one might have anticipated some of the additional tilt and settlement cause by the drilling of the underpinning piles. In Italy, inclined soil boreholes were drilled on the high side of the tower and allowed to collapse to correct the tilt of the tower. At Millennium Tower, the drilling of the underpinning piles opened boreholes along the low side of the building that likely experienced soil squeezing to some unknown degree. One can anticipate that the drilling of these boreholes would make the settlement and tilting worse, which appears to be the case here. The bottom line is (1) the geotechnical conditions vary across the building footprint both in soil layering, depth of water table, and the effects of nearby construction, and (2) the foundation retrofit construction may have introduced more factors affecting the building performance. This is a very difficult design problem to identify accurately and to solve in the optimum way. The unfortunate thing is had the original piles reached down to bedrock, the whole dilemma could have been avoided,

@KameraShy

2 жыл бұрын

That seems to be common sense, understandable by even a layperson like myself with no engineering degree. In particular, one would think that evaluation of potential future construction in the area would have been considered in their planning. Government projects are talked about years in advance.

@mikeshort4291

2 жыл бұрын

Save two million now, spend 20 million to fix it later. Sounds like a typical government job.

@davidb6576

2 жыл бұрын

@@mikeshort4291 No, this was a private-sector decision to maximize profits through shortcuts, then soak the tenants through remediation costs. Look at the Hoover Dam, a government project done right at high cost, but without expensive fixes required later due to proper construction methods.

@emmabovary1228

2 жыл бұрын

William, is this the same effect you see when inserting candles on a cake? If you try to place too many candles on a cake that’s too small, each candle inserted affects the candles nearby. Eventually, only the candles on the outermost area can stand straight and all the others are not only leaning but the cake underneath is pushing each candle around. Thank you

@williamisenhower2251

2 жыл бұрын

@@emmabovary1228 It is a related effect, but not exactly the same. The problem you are describing is usually caused by driving displacement piles (i.e. solid circular or square cross section piles) in a tight pattern with the order of pile driving from one side of the group to the other side. Some times this seems like the only way possibly. As an example, consider a project on property on a river bank. Here many pile driving contractor will argue that if the piles were driven from the center of the pile group outward that the pile driving equipment will be trapped on the water-side of the pile group. My answer to the contractor has always been, "That's your problem. You should have recognized this problem and accounted for the expense of moving the equipment in preparing your construction bid." I worked on a job in Charleston, SC where this happened as I described above. In this case, some of the first piles driven along the river bank were displaced by over 9 inches laterally from their planned positions and could no longer properly line up with the columns they were supposed to support. In this case, it might have been done this way deliberately because the general contractor deliberately under-bid the job by $6 million to be low bidder then filed claims claiming a defective design in order to reach a profit. At Millennium Tower, the underpinning piles are drilled. not driven, so there is no displacement effect, but the boreholes for the underpinning piles can squeeze-in if too long of a delay takes place between drilling and placement of concrete in the boreholes. This occurred at Millennium Tower when one of the boreholes was open for four days, where as a typical time limit is around four hours. The tower moved at an increased rate while the borehole was open.

Even to a nonprofessional, however, architecture aficionado, your videos are a pleasure to watch and full of very valuable information. Thank you!!

@sophocles1198

2 жыл бұрын

He is a natural instructor

I would trust Josh over any other "consultant" similar to SGH or others. He carefully explains needs, causes, conditions, solutions and information in a way that a non-technical building engineer customer can understand and can follow the level of detail to assure the honest evaluation and completion of a project. Thank you Josh for your many excellent videos about a variety of subjects and projects.

@BuildingIntegrity

2 жыл бұрын

Thank you! Means a lot!

1. The building foundation is already failing dynamically. 2. The original foundation analysis and all subsequent analysis are flawed in respect to static vs dynamic analysis. 3. The building is already beyond the ACI limits and will continue to increase its differential settlement until it reaches a tipping point beyond which the rate of differential settlement will begin to increase at an exponential rate. 4. The soils report on which the foundation was based was fatally flawed and any solution that relies on that soils report will also be flawed. 5. The installation of piles to bedrock on only a portion of the foundation is not a permanent solution. Piles on the rest of the perimeter will need to be installed as

@cliffyoung5712

2 жыл бұрын

Did not intend to hit submit. 5. The proposed partial pile solution is likely to increase the rate of differential settlement 6. This building will be demolished within the next 10 to 25 years. 7. Lawsuits make for terrible structural solutions. 8. That foundation design would never been signed off on my plan check table.

@ehombane

2 жыл бұрын

for submitting by mistake you the the option of editing the comment (this is as simple) Just click on the three dots on the right, then edit. oh, the dots can be seen only when you hover the pointer above your comment. and fixing the tilting is as simple too. Inject sand at high pressure under the compressed side. quite cheap. or even cheaper, drill a mesh of thin holes on the other side, in order to sink evenly and not lean. but this requires better computing and soil compacting knowledge.

Very concerning indeed, to the tenant who first put a marble on his living room floor and when he let go, it rolled away...pretty quickly. I have lived 25 miles North of S.F. for 58 years and am VERY concerned about the next big earthquake, not only as it relates to this building but those in the area.

Hey Josh, another Josh here. As a former geology student, I'd like to point out that in any seismic activity, P wave propagation is going to be of grave concern here. There are now two forces acting upon this building. The building now has asymmetric foundation loading. The moment of inertia is no longer directly above the center of mass. In fact, you have now created a large lever above grade. Even worse at the foundation, you now have an inclined plane or a wedge because of the angle of thrust induced by the fact that the large concrete foundation is now being loaded asymmetrically.. I'm not an expert, but I would imagine that the forces would then be exponential rather than additive. Simply put, the building above ground is now pivoting on the fulcrum at grade with a huge amount of mass acting on the pivot point. And to make matters worse, the shape and action of the foundation underneath is now acting as a wedge as if a chisel to pry the earth aside. Their goal for remediation should be to recenter the building over its center of mass so that any P wave compression going through the building will not induce asymmetrical loading on the foundation.

@rrice1705

2 жыл бұрын

Makes sense, but how would they do that? Add a counter-weight to one side?

@jbrucksnc

2 жыл бұрын

@@rrice1705 not sure, but yes that approach was used on the leaning Tower of Pisa to actually undo some of the lean!

@jbrucksnc

2 жыл бұрын

@@rrice1705 even something as heavy as millennial Tower can be lifted if one has enough leverage. This may be overly simplistic but I believe they should drive larger piles down to bedrock then install a series of hydraulic jacks to slowly lift and straighten the building.

Planning and building a concrete block wall a some years ago (which I'd never done), I looked up what the specs were regarding the depth of the footer/foundation necessary to do it correctly. I was surprised the spec was not DEPTH, but WIDTH: the footer was to be twice the width of the block which was 8 inches--so a 16-inch-wide footer. It's served me well as my wall is 24 years old and doing fine! Now comes this tilting building whose "footer" is not twice but about the same as the width ! The physics are the same; without bedrock support who is surprised this thing's falling over?

@dohc22h

2 жыл бұрын

Either a bunch of Monkeys were in charge of this Building's construction... or it was a Deliberate act put into place to make a lot of Money for a few People.

@ronaldfharring7326

2 жыл бұрын

Your simple comparison illustrates basic foundation principles which should be inviolate. If ever a project requires over engineering and redundancy, it is a skyscraper in San Francisco.

Another excellent video Josh. I repair structural concrete and failing foundations and install screw piling and I find the best way to arrive at an engineered solution to a problem is close collaboration between the engineers and the construction company that is experienced with the type of work being engineered. Josh, you are really good at looking at the solutions different engineer's arrive at and then applying practical construction knowledge and experience along with your engineering skills to arrive at the best option. And your also so good at explaining it to us. Regarding the Millenium Tower, in my opinion there is no practical way to save this building. You made an excellent point of what happens when there's an earthquake and there will be one. The foundation and original geo tec engineering was never designed to support the building on this piling repair. I look forward to your next video on this building but I think the Millenium Tower is a goner.

@BuildingIntegrity

2 жыл бұрын

Thanks Gary for the kind words. We will briefly mention the type of foundation repairs you do because multiple people have compared what they are doing to this building to those types of foundation repairs and saying... "see, we do this all the time"

The building tilts - but everything is fine, you ninnies. But we'll effectively poke a rock under the bad side. What could go wrong? It sounds like a bunch of engineers at a backyard bbq trying to jack up a car and no one is listening to the one sober guy.

@Mizz.Person

2 жыл бұрын

😂🤣😂 Soo true.

@user-dg9pu4pe9d

2 жыл бұрын

In the end they end up with a Rube Goldbergesque contraption that no sober person would think is a good idea.

Excellent series. Thank you. Also makes me glad that I bought a single level ranch house on a couple of acres in the woods.

@robertslugg8361

2 жыл бұрын

But are any of those trees leaning? ;-)

@edp2260

2 жыл бұрын

Good choice. The best in my opinion.

@jackson_68

2 жыл бұрын

@@greggoog7559 And everyone DESERVES the same living conditions as everyone else !!!!!

@LuckyBaldwin777

2 жыл бұрын

I did the same as you. Then a PG&E fire came through and took everything. That's when I learned I wasn't as smart as I thought.

@LuckyBaldwin777

2 жыл бұрын

@Ben Chuft 200 foot tall wall of flame came roaring up the canyon driven by a 50 mph wind and I survived the firestorm. Many others didn't. I call that lucky.

This episode is a real cliff-hanger! - I hope Josh posts Part 4 soon.

@petersack5074

2 жыл бұрын

Sylvester Stallone, ? was a 'cliff ' hanger.........if that tower, toppled, there would be alotta '' hamburger '' killed persons, by the thousands...

@rrice1705

2 жыл бұрын

Part 4's sub-title may well be TIIIMBEEER!

Maybe San Francisco could just redefine what straight actually is.

@SteamCrane

2 жыл бұрын

As long as it leans left, it's OK.

@testaccount4191

2 жыл бұрын

@@SteamCrane just don't let them walk around to the other side of the building

@cavalheiro2062

10 ай бұрын

Maybe if they put a rainbow billboard on the roof and/or a floor garden everything will work fine.

Such an intriguing story, so well told, that I wish it weren't broken into chapters. I could listen to this for an hour.

Interesting how the liquefaction effect of an earthquake under the side of the building not with bedrock support can be quantised which would appear essential. Also will the bedrock bounce be more direct under the hard piling than on the soil friction support side? What asymmetric forces will that put on the building structure? A very interesting situation. The Leaning Tower of San Francisco is just as fascinating as the the one in Pisa but best viewed at a distance from ground level I would think.

@KameraShy

2 жыл бұрын

If the underpinnings are asymmetric, could it split in half as it sinks?

@ehsnils

2 жыл бұрын

Even a small quake could cause trouble. I'd stay away from SF.

@stillraven9415

2 жыл бұрын

I'm happy to be a state away! None of the buildings out on that landfill are safe.

@cookinmamabree6939

2 жыл бұрын

@@stillraven9415 in happy to be from a town that construction workers never get past 5-6 floors, before the crew gets drunk on shine. The highest building for 50 miles, is a holiday inn

@SteamCrane

2 жыл бұрын

@@KameraShy It is already splitting. Foundation is cracking.

Fascinating as always, for a curious layperson like myself the scale of the engineering challenge here is pretty nuts. Looking forward to the next video!

I honestly check this page every single day to see if he's added new videos. I'm not an engineer or an architect- in fact, I'm studying accounting and I work in aviation.

I am so happy that the owners of the Tower are very wealthy people. Usually, it's the poor who suffer from poor construction. The gentleman's discussion is so hedged and repetitive that it is good to watch before going to sleep.

I am by means no an engineer, but I think the partial foundation with piles supporting a part of the building is a kludge that will cause more failures in the future.

@---un5mt

2 жыл бұрын

Exactly, what if then the building starts tilting in the other direction? Haha.

@GH-oi2jf

Жыл бұрын

@@---un5mt- They want it to tilt in the other direction, which will reduce the out of plumb condition.

I have zero qualifications in this area but my common sense analysis is very basic: They don't know what they don't know. History is full of examples of beliefs/assumptions/calculations not applying the same way in Situation-B as they did in Situation-A.

The provision of a solid corner supported from bedrock while leaving the rest of the building essentially free-floating surely causes a major problem. As the building is too heavy for the soil it will continue to sink, except for the section that is attached to bedrock; this should crack the foundation and totally destroy the building.

@verngoossen2020

2 жыл бұрын

Transcona elevator failure search

@verngoossen2020

2 жыл бұрын

Geostrata-Mar/Apr 2019-

@GH-oi2jf

Жыл бұрын

The mat should rotate as the side opposite the new pilings sinks.

A friend of mine is a construction engineer - concrete-truss hangars for agricultural vehicles are his specialty - our military is bombing his city mostly at night and early morning to prevent them from sleeping, so he's spending nights watching your videos. Thank you, from both of us!

I am a teacher for arts and computer science and have nothing to do with building, but those videos are really interesting and understandable. I wish there were more professional engineers that were able to explain their thoughts and work this well for non engineers.

Have loved your video series about these topics as a fellow structural engineer (albeit in the bridge realm). Would love to see a series about the Hard Rock collapse in New Orleans in the future if there is enough information out there to create one. Keep up the great work!

@roadtoad7704

2 жыл бұрын

Hello. With your knowledge of bridge design, I could ask you many questions. I'll stick with 2. The I-40 Memphis Bridge: If the discovered fracture was present for 2+ years, how did the bridge remain intact? Redundancy? 2): I've always been amazed how much older structures were seemingly over built. One being the Mississippi River Frisco Bridge, 125+ years old and can safely support 15,000 ton BNSF coal trains. Completely boggles my mind.

The Italian engineers finally fixed the Leaning Tower of Pisa by lowering the high end as opposed to raising the low end.

@thevictim2072

2 жыл бұрын

I was shocked at the idiocracy of Mr. Hamburger and all the so called engineers that approved of this ridiculous plan to cause the failure of the building. Did anyone pay any attention to the work done at another leaning tower. The answer was provided and no one could see it???

A wise person once said 'Perception is reality'. That's the core issue here - because of the history, and also the unfortunate and over-the-top media coverage, the general public has lost confidence in this building and in the people who are responsible both for its original design and the proposed fixes. It's not clear how that confidence can be restored, but at least in the short term, restoring public confidence is more important than actually fixing the building.

@kevin3434343434

2 жыл бұрын

It will never be restored. The only solution is taking it down.

@qwerty112311

2 жыл бұрын

Tear it down and have a different everything - developer, engineer, architect, etc design a new one and build it

@tuvelat7302

2 жыл бұрын

The settling of this building will be accelerated in an earthquake. It is built in a liquefaction risk zone. It needs to be fixed, not rebranded.

Thanks for another very interesting and informative episode, Josh. This is fascinating not only for the engineering issues, but is somewhat personal for me. Over four decades ago I worked in that neighborhood and walked by that site every day.

I think tearing the building down would be the simplest solution (and maybe even the cheapest after taking into consideration all the circumstance regarding rescue attempts). SF has a lot of landmarks and doesn't have to become another Pisa.

@GooberFace32

2 жыл бұрын

Came here to say this. At this point, it might be cheaper to buy the building back from the condo owners and implode the thing.

As a layman I predict that they chose the solution based on simple conditions like "it wont impact the residents as much" and "it seems like the best option when you explain it to a child" and "wow I am under a ton of pressure Im going to pick a solution fast " instead of "we have really done an in depth analysis and the situation absolutely is this one even though it is ahrd to accept and explaining it will make some people mad".

Whenever considering fixes, I like to ask the engineer if he would have built it that way from the beginning? The answer is always no. This building in my opinion is doomed, the reason is that they are focusing on the perimeter of the slab, while ignoring the rest of it. They will introduce stresses to the slab that it was never designed to deal with long term.

Frankly, I'd hate to have friction piles.

At what tipping point is it too dangerous for workers to tear the building down in enough time, yet you can’t leave it bc it will be falling onto other structures.

@mendelde

2 жыл бұрын

Leaning Tower of Pisa is doing fine

@stillraven9415

2 жыл бұрын

@@mendelde have you seen the extreme lengths that they went to stop that tower from falling over? The trick that they were trying came from how they stopped that tower from falling, but the conditions are not the same.

@Helladamnleet

2 жыл бұрын

@@mendelde After extensive work to stop it from tipping, yeah

@mendelde

2 жыл бұрын

@@stillraven9415 @Helladamnleet Pisa 4⁰, Big Ben 0.26⁰, Millennium Tower 0.11⁰ (2018 value) is not anywhere close to tipping

@davidb6576

2 жыл бұрын

​@@mendelde Unstable soils in an earthquake zone. I'd not be too nonchalant over its tip angle.

"Hamburger" came up with this? We are in trouble already.

Exactly. More tilting, increase in offweight so it will tilt over (Faster and faster) in time and then nothing can be done. It has to be destructed and rebuilt.

@frankmiller95

2 жыл бұрын

How about part one, but not part two?

I am glad you are on the case! They definitely have not addressed these major concerns on the news, it doesn’t look great for this tower.

I’ve taught engineers and architects about polymer products - adhesives and coatings. I am not an engineer but I employ 5 extremely smart engineers. The engineers and architects that I taught did not impress me with their intellect. An example - Boston’s Big Dig tunnel - largest and most expensive civil construction project in the US. The engineers (none that I taught) attached large concrete roof panels and used a polymer adhesive with no mechanical fasters. Polymer “creep” is widely known and understood which makes it creep under vertical loads and fail. Big concrete panels falling onto cars killed people and the redo was extremely expensive. This is a well known phenomenon- the engineers on this tower are guessing and have theories on why they can fix this. We’ll, theories are like Arseholes - everybody has one.

I always enjoy your videos. Construction and engineering are interesting, the application of principles of physics and other sciences in the real world. You have a talent for presenting facts clearly in a way that makes them understandable for an interested amateur.

Another great video Josh, a lot of drama. The Tower is now infamous, and I can't imagine any of the residents will want to live there. There is a lot of liability for any engineer to certify that the Tower is safe.

@ralphholiman7401

2 жыл бұрын

I'd sleep in my car before I would sleep in that building.

Thank you for informing us on this building nightmare. I wouldn't even live there for free. Peace🌎💞💝

What if they had agreed to install the test piles on the sides that are not sinking & tilting 1st? Worse case the building straightens out and we could have learned from this the means and methods to be used once we began on the sinking & tilting sides?

@disklamer

2 жыл бұрын

Reinforce the good side before working on the weak side, I like the idea.

@---un5mt

2 жыл бұрын

Because reinforcing the non tilting side means more money. I’m concerned that in the future, the side not currently tilting will begin to tilt given that it will have no reinforcement pilings to bedrock like the other side. They literally decreased the number of pilings they will be installing on the tilting side from 52 to 18 due to price.

As always ,a fascinating explanation of a complex subject in layman's terms ! Cheapest solution caused this problem in first Place! Piles to bedrock was going to cost $30 million more than the piling solution cost! Thnx very much !

@joedo3529

2 жыл бұрын

Last report I saw was it would have cost only 4 million more for the piles to bedrock.

@miltronix

2 жыл бұрын

@@joedo3529 That is true from all we have heard.

I would like to know details about the Salesforce Tower. Did they drive the piles down to bedrock? I bet they did! The Salesforce Tower is HUGE, and that building has no issues as far as we know! The contractor that built the Millennium Tower made a big mistake by not driving the piles down to bedrock! A little to late now to fix it. Should have done it right the first time!

From about the 25th floor, up attach massive straps to the core on every other floor and spool them out in the southeast direction between the 199 Fremont Tower and the Park Tower located on the corners of Beal and Howard St and attach them to a massive anchor placed in the ground out front of 285 Main St and winch the building straight. While the building is being held straight by the straps sink the piles to the bedrock on all 4 sides and then attach the building to the new piles on all 4 sides. If the Tower sinks while the piles are being driven it won't matter because it will remain straight by the tightening or loosening of the straps. Remove the straps and you're done If you have not already guessed... I am not an engineer But I can Macgyver and this would work

@FutureSystem738

2 жыл бұрын

LOL :-)

I couldn’t click on this video fast enough.

If none of the solutions proposed will fix (arrest) the sinking of this building, demolition companies place your bets. Thanks for the info, excellent video.

Another big like from me. Best utube channel. As a construction inspector with the NYC dept of Buildings, I find your videos incredible eye openers. Thank you

something that says a great deal about you is that your explanations are accessible to non engineers. the public good depends on an informed public to begin with. thank you.

It is crazy that anyone would ever want to buy any condo in here. You run the risk that any fix is temporary and then in the future the current owners get stuck demolishing the building which the price of the lot likely won't even cover. No attempted fix is provably a fix. The "fixes" seem like cheap mitigation to trick owners into letting the builder walk away from liability. Millennium Tower should be renamed Bagholder Tower.

@Sashazur

2 жыл бұрын

You’re right, but if you did buy one you probably could get a pretty good deal!

If this guy is saying there isn’t a problem why isn’t ACI or his professional organization sending him a letter to stop saying those things without stating that the tilt exceeds limits

@ocko8011

2 жыл бұрын

That's a risk he's willing to take to make content about things that actually matter; he may also be protected under a creative licenses, ethics would have us believe any public comments are harmful to individual integrity but it should be up to the listeners to use their own judgment and view this content as a non-technical summary. I'd prefer to hear this take then one from a professional journalist.

@patrickmorrissey2271

2 жыл бұрын

I think when mark w says "This guy", he is talking about Mr Hamburger.... Not Josh. which I agree, and wonder about as well. Mr Hamburger (more or less) says "There's nothing wrong here, everything is fine, we're just doing this to quiet down rowdy unit owners"... Where is ACI on this??? Even Josh says "the way I read it, they are out of spec on this." What is ACI saying??? Or are they saying nothing, out of fear of being sued??? Or??

@_PatrickO

2 жыл бұрын

@@ocko8011 Grow up ocko. He isn't going to use hearsay as definitive evidence and is coming from a neutral perspective so we know what the disputes are. Anyone covering this as if everything is an absolute would be a liar. Those claims of being out of spec are technically disputed and hiding the existence of the dispute would be misleading. You are being presented information in an even keeled way so that you can make up your mind as a juror and not simply be manipulated by any one side's claims. After watching his video, my opinion is that the builders are faking fixes to trick current owners into accepting a fix that lets the builders run away. Then in a few years(preferably after any statue of limitation pass) the owners get stuck holding the bag for demo costs when the building keeps having too many issues. The builders/architect just need a "fix" that lasts long enough for them to escape liability. The current condo owners should be negotiating as if the building will be torn down and not accept a dime less.

@ocko8011

2 жыл бұрын

@@_PatrickO Thank you for your take on this subject. Discourse is a valuable tool. There differently is a good possibility that the owners are being sold a pig in a poke. Geophysics can make fools of the best engineers.

@williamhaynes7089

2 жыл бұрын

@@patrickmorrissey2271 - i would assume aci makes the standards, local code is taken from it and enforced locally...

Thank you so much for taking a measured, deliberate approach to your coverage of this situation. There is so much to unpack here and I agree that there are many different discussions to branch out from this point which each warrant their own separate videos. The potential asymmetric connection of the building's foundation to bedrock is certainly a major topic to be analyzed especially in a seismic event. This could be one of those instances where the unintended consequences come back to really bite one in the donkey. Keep up the great work!

Thank you for another interesting video. Looking forward to your next.

Bog standard layman here.... Fascinating read. I can see logic in most of the opposing points of view. But they are all based on engineering and design concepts. Q: What is the point of an empty building? Who in his right mind would sign a tenancy agreement in the Millenium building when a major part of commercial buildings are vacant in most cities? - a worldwide phenomenon it seems. Who would buy an apartment there? Mum and Dad's basement suddenly would look very secure. So all of the discussions on repair and possible earthquake effects may all be (already?) moot. Of course all those with skin in the game will resist a tear-down. I think that decision will be made by a San Francisco authority in the not too distant future. I have no idea of the political and governing situation in San Fran , so will leave that to others.

Thanks for the report Josh ~ fascinating to follow this dilemma ~ I’ll be waiting for your next video ! 👍

The Italian engineers finally fixed the Leaning Tower of Pisa by lowering the high end as opposed to raising the low end. I’d love to know how they came to that solution.

@annaksfrog

2 жыл бұрын

Me two.

@thevictim2072

2 жыл бұрын

They tried lifting the low side and that caused further sinking of the low side

@verngoossen2020

2 жыл бұрын

@@thevictim2072 The mill tower ----- they need to drill on the High side to lower it --- they could pull it back-------------------------------

@williamisenhower2251

2 жыл бұрын

The engineering analyses used to come up with the solution to the Leaning Tower of Pisa problem were the product of advancements in geotechnical engineering, computational mechanics for nonlinear stress analysis, and improved computers (both speed and size of memory) since the late 1940's to the early 2000's. First, the geotechnical engineers had to develop an understanding of the soil layering and soil properties underlying the tower and the area around the tower. This including measurement of the strength, consolidation, and deformation properties (including fully-drained creep behavior) of the soils present at the site. Simultaneously, the computational mechanics (i.e. computer programs) for nonlinear stress analysis were developed (primarily for the aerospace industry, but later adopted for other applications). Lastly, computers needed to be improved to the point where the computations could accurately model the past behavior of the construction and settlement and tilt of the tower accurately. Once it was possible to match the computation predictions to the historical records of settlement and tilt of the tower, various scenarios for repair could be modeled with a reasonable degree of confidence that the predictions were accurate. Then the effectiveness of different repair methods could be compared. All of this work was evaluated by international panels of experts assembled by different Italian governments over the decades. My recollection is that the panels concluded that doing nothing was dangerous due to structural collapse. So, they placed stabilizing weights on the high side of the foundation in an effort to slow down the increase in tilt and erected the guy wires to the tower to prevent excessive deformations during high winds and earthquakes. Then, over several years, different repair methods were modeled and evaluated. It was concluded that the safest was to stabilize the tower was to drill a number of inclined boreholes under the high side of the foundation, then allow the boreholes to squeeze shut, which caused a reduction in tilt of the tower. Various models were tried to determine the best number of boreholes to drill, plus the borehole diameter, angle from the ground surface, location and length, etc.

@thevictim2072

2 жыл бұрын

@@williamisenhower2251 You sure do know how to write a bunch of words and not say anything. Very impressive. Just to let you know. I stopped reading it after the 1st sentence.

I agree with Mark W... if we look back at the Hard Rock In NOLA and see videos workers made of support jacks bending at their limits and still nothing was done. It even took a long time to recover the bodies of the men who perished and seems like that would motivate people to do more BEFORE a tragedy... or does it take these earth shattering events of loss to make people do something?

Left hanging, want more! Love this series.

Josh thanks for trying to help us whose callings were in different paths in life. Building and living in San Francisco has a lot of challenges. I hope they get this mess sorted out and a solution can be reached that will stabilize this structure and does not become a burdensome expense for those who have invested dearly in this structure. But all large urban centers are faced with getting the most buck for the bang. I life about 20 miles from a Top 50 US population center. The town I live in has all the modern connivences that the down the highway urban center has with some elbow room. But it too is beginning to require major financial resources in living here.

The safest way to stabilize that building is to evacuate the top twenty-five floors and remove every removable pound of weight. Weight reduction of the top twenty-five floors is the best solution. Reduce sinking weight, and improve center of gravity. Yes, it will cost a massive fortune and lead to legal fights, however, it is now a public safety concern. One must consider the possibility of that building going over when the next earthquake strikes. Even a small shaker could be enough to send that building over, and on to other buildings and people. The destruction and casualties would be catastrophic.

6:45 literally made me swallow my beer wrong, and cough my eyeballs out with laughter

Yes, building a large blimp over the building to suspend it was considered but rejected due to the shadows that would have been cast. Also rejected was building two large side walls and then allowing the building to 'hang' between them. Some thought that it might just become a large pendulum if the wind was just right. Also rejected was closing the roadway and building another building so it could lean against it.

@joevignolor4u949

2 жыл бұрын

There is a fix for swinging in the wind. The John Hancock Tower in Boston has a huge concrete slab up at the top that is mounted on tracks. When the building sways because of the wind electric motors push the heavy slab in the direction of the sway to push the building back in the opposite direction to damp out the sway.

Sophisticated solution by the engineers: "According to my calibrated thumb, i estimate that this should probably work."

People will lose money, but they need to bring it down. Experimenting with the building and surrounding area if putting lives at stake.

@KameraShy

2 жыл бұрын

As well as every other structure in its vicinity.

Josh, Very much enjoy your videos and insight to these things. Would love to see more of your company's case study videos also.

I won't lie, I would think twice about buying a half million dollar condo once I saw the disclosure about the building being 2' off vertical. Heck, I'd think twice about buying a condo in a neighboring tower.

Cutting corners never cuts cost, in the long run. The biggest problem we have is that, as a limited liability company, the responsibility never lands on an individual, who has to take final responsibility. Shareholders can sell off while the project looks good at a, more than reasonable price, before problems are seen. No wonder there is so much money involved in "Property". On a technical note. A lot has been learned from a previous leaning tower, I'll let you guess the name of that one. Re-Piling the lower side to the bedrock is obvious and easily understood, especially to "ShareHolders". However, this will require intermediate installation of, at least a large diameter pile, to the bedrock, at the centre of the raft slab, the slab should also be considered as part of the foundation, and then install pile as the higher end sinks, at which point it should rest on the centre piling. Or, on the other hand... They should have done it properly and listened to people that know what they are doing and not just your cousins next door neighbours cat.

Thanks Josh! I hope they figure _something_ out before we have a re-enactment of CTS in the middle of San Francisco. I can understand the temptation to jeer at these million-dollar-plus condos (I'm not made of money either), but the fact is a building collapse is bad news for _everybody_ in the long term. 👍️

Why aren't holes being drilled on the high side to get it to level out? It's working in Pisa.

what happens with the dishing? twice the dishing is bad, too, right?

knew a civil engineer in Spring 2020 who was heading to SF, to work for the underpinning contractor

really interesting video, looking forward to the rest of the series

Thank you for sharing!

Great videos! Informative and entertaining.

A building this tall w/ a very small footprint should've been supported by rock, no question. What Mr. Hamburgler is saying is just political. Makes the City Council look ...not so bad. The building owners & the City owe the residents.

The historic Leaning Tower of Pisa was successfully righted. It was a particularly difficult task due to the age. By bringing in experts in different spheres, all working in unison, the task was carried out with the eyes of the World on it. I visited in late 2019 and was staggered at how much the building was nearly upright. If we have the experts to pull off this huge task, with a guarantee that it will not tilt again, surely San Francisco can do likewise. All they have to do is ask for help.

@joevignolor4u949

2 жыл бұрын

While similar the two problems are not equivalent. The Leaning Tower of Pizza weighs 29.4 million pounds and is 183 feet tall. In contrast the Millennium Tower weighs 686 million pounds and it stands 645 feet tall. As such the Millennium Tower is 23 times heavier and 3 1/2 times taller than the Leaning Tower of Pizza. Also, the Millennium Tower is in the center of a large, crowded, busy modern city and the ground conditions under the two structures are not the same.

Keep up the good work mate 👍👍👍👍

I wonder if the better solution would be to get the other side of the building to settle faster rather than stopping the settlement on the sunken side.

@larrybe2900

2 жыл бұрын

Perhaps not faster but just enough to arrest the tilt currently happening and know that it works.

@GH-oi2jf

Жыл бұрын

The way to get the east side to settle faster than the west side is to support the west side. That is what the remediation is doing.

Every disaster movie has a Ron Hamburger character in it

You do an awesome job explaining this stuff

Tipping can't be okay. Josh, I can't stand it when someone thinks that they are the smartest person in the room. Is this solution actually a solution or is this lip service? Is knocking it down and starting over an option or would that be a huge mistake? So many questions still. Thank you Josh, please keep us updated.

@nobody8328

2 жыл бұрын

Don't forget to tip your service provider, though! 😉😆

@shAnn0n1

2 жыл бұрын

@@nobody8328 that's hilarious 😂 I didn't even think of that 🤣

@martentrudeau6948

2 жыл бұрын

Agree, tipping is not OK. It's a new building that should be built plumb!!! -- The residents should get a refund of their money. -- I believe the tower isn't safe and it should be torn down. No one has ever built a building with friction piles on one side and piles driven to bedrock and the other side before, how can they know if it is stable or not? They don't know!

@BillyLapTop

2 жыл бұрын

Removing the building altogether may create problems for the other structures around it, since it is alleged the transportation terminal project may have been the cause of Millennium Tower's loss of stable soils. The whole thing is a fiasco, initiating when the design was changed from steel to concrete, massively increasing the loads on the friction piles. Removing the tower may create problems with the stability of the soils the other buildings stand upon, even though some are piled down to the bedrock. Couple with this that the tower is also experiencing lateral/horizontal shifting now. What effect does that have on the surrounding soils as well? Seems every solution from dismantling to modifying piles down to bedrock has its problems. Hamburger's assertiveness in his article reminds me of the Titanic. All I know is I would not want to live in that building on top of an earthquake zone, depending upon mass dampers that are already off center, trying to keep it true, which already adds to the asymmetry issue.

@martentrudeau6948

2 жыл бұрын

@@BillyLapTop ~ Holy cow, mass dampers are in there too, I didn't know. Once the Titanic hit the ice berg, it was doomed. So with the Millennium Tower, once friction piles started to settle unevenly, it too is now doomed. It's inevitable.

As the building tilts, the centre of gravity of the building will shift towards the side that is sinking. This will compress the soil on that side even further and release pressure on the side that is not sinking. There should then be horizontal movement of soil away from the sinking side, thus exacerbating the rate of sink. None of this is good for the foundation slab, which is clearly failing. The proposed 'solution' appears to be one that protects property values in the short term, rather than protecting the building and its occupiers and residents.

@larrybe2900

2 жыл бұрын

It almost seems like the time taken will end up with its own solution.

@joevignolor4u949

2 жыл бұрын

@@larrybe2900 Just make sure you are not in downtown San Francisco when the solution occurs.

@joevignolor4u949

2 жыл бұрын

Even if the foundation doesn't completely fail as the building's center of gravity shifts away from the center of the foundation the torque loads on the building's structure will increase and the building will inexorably approach the point where it will structurally fail and collapse. It's like a stack of boxes. The taller the stack and the more the column is leaning the easier it will fall over. Some have also theorized that eventually the plumbing and elevators in the building will stop working and windows will start breaking because of the structural distortions caused by the tilt.

How awful that there is a channel called building integrity that focuses on buildings without integrity. 🙄

Really interesting - I'm looking forward to the next video on this!

Educational and entertaining. Thank You, for tackling this ......

The people who say, "Do nothing, surely it will fix itself!" are proof that we need to educate more engineers. When has ignoring a problem of this magnitude ever made the problem better?

good to see you again!

You're videos are awesome, B.I.! Thanks

Thanks for your input!

Really enjoy these videos, even though I am a EE/embedded guy you explanations and graphics appeal to my inner ME/Civil geek.

I would imagine in the event of an earthquake, the pilings resting on bedrock would reverse-jackhammer upward toward the building? Update: On re-viewing this video the second time, it occurs to me that the foundation design for the Millennium Twr was flawed even before city hall approved its building permit or the third party evaluating the submitted plans has dropped the ball. I recall that the foundation of former World Trade Ctr twin towers in NYC were surrounded by a reinforced concrete 'tub' to expand into the NY Bay because there wasn't enough real estate to build it on. A similar tub-like basin would have solved the unstable soft ground in the Millennium case. In my opinion, the 10-ft thick straight flat platform on which its sits now over a forest of pilings does not resist lateral translation of the massive load. Stand one-legged onto a lump of clay and one can see the uneven lateral shift even as that lump flattens down and the clay squishes up around the edges of your foot.

@joevignolor4u949

2 жыл бұрын

The biggest problem in an earthquake, especially in San Francisco, is that the ground goes sideways back and forth. This is why if you look at pictures taken after the 1989 earthquake in San Francisco there are many structures that went sideways and fell off their foundations. The is some up and down movement as well but with the Millennium Tower the biggest concern would be how well will the building's compromised foundation cope with the sway.

It's not just Code observation. The initial response to the cladding behind UK's Grenfell Tower fire, to charge homeowners in all other properties affected by similar design flaws, has settled down in the wider legal framework of correcting design flaws being to the charge of the maker. Cars, washing machines, these are classics. A similar issue was the Miami Surfside Champlain Towers collapse, where the Condominium Owners got equally hung up by original design flaws.

Great work, as always, thank you!

Thank you for sticking with this. I sure you have lots of things you could do. But there are some very serious legal issues in this matter which have not come to public attention. Some of these issues cut directly at public trust in San Francisco and California development building processes. I have no idea how many people will end up in front of a judge or what sorts of civil and criminal claims will be heard. Accordingly, I won’t talk about the corruption issues that are known to many involved in these cases. Time and people like you will bring the guilty to the light of day. Only focus by arm’s length parties will avoid the political “fix” that was negotiated a year ago to keep this monster out of the 2022 elections in California. Please stay on this.

Who were the geotech firms who criticized SGH's solution? If Mueser Rutledge had been involved, this would not have happened.

Another great episode, thanks for sharing.

Maybe it's not about public relations or safety. but it's about not being able to physically fill your wine glass all the way without spilling it. it's about not getting dizzy walking around in your rooms. yep, that's rolled into the "value" for sure. just like we watched marbles roll across the floors. even your cat won't like it there.

Was any proposed solution to sink more the other side to even it out as much as possible? Living in Pisa this has become quite fascinating to me for obvious reasons haha

@williamhaynes7089

2 жыл бұрын

they fixed that after many attempts and left it leaning for tourism reasons

Thank you for sharing your knowledge and experience