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Purdueenginerd

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Everything posted by Purdueenginerd

  1. Purdueenginerd
    I tried to buy in Midtown in 2014. Prices rose so fast in like 2 month period that I got priced out.
  2. Purdueenginerd
    Looks like theyre about to test some piles.
  3. Purdueenginerd
    First I've heard of this, I guess from a pure development standpoint it makes sense and is positive. But breaking into political discussion here a little bit, is there evidence of MLB teams using these style developments as leverage against the public for stadium subsidies? I generally oppose subsidizing taxpayer dollars for new stadiums, but that dynamic could change if said MLB team is building hotels, apartments, and a litany of other businesses.
  4. Purdueenginerd
    Thats interesting. Is it common for MLB teams to be in the development industry for mixed use, etc?
  5. Purdueenginerd
    Theyre definitely doing something with the foundations. You can see the top of the pier exposed and all the grade beams. I dont see any distress from the photos however. Interesting. Wonder what manifested so late in the project.
  6. Purdueenginerd
    Anecdotally my wife and I both distinguish between target and walmart. In my opinion, especially when I was younger an had less money, Target's clothing department was superior to walmart in fashion and quality. Granted its probably been like 10 years since I'e bought Any clothing there. I prefer target for other reasons. Only time I ever really go to Walmart is if I'm out of town and forgot to pack something I need.
  7. Purdueenginerd
    I'm just picturing a lab room full of Proton Packs from Ghostbusters and a big danger sign that says "Warning! Dont Cross the streams!"
  8. Purdueenginerd
    Using Emporis, between 500 and 600 feet buildings, Houston has about 18 completed high rises on that website(not counting under construction and transmission towers). At a cursory level, looks like wikipedia is mostly correct albeit their table is slightly misleading. he table should have a range, but they just put greater than or equal to. So yes, Houston has more than 18, 500 footer buildings, but between 500/600 the table is correct. https://www.emporis.com/city/101031/houston-tx-usa/status/all-buildings/2
  9. Purdueenginerd
    Supertalls, even in cities as Dense as NYC are rare. NYC only has 12 buildings that are over 1000 ft and 3 of them are what I would consider hyper rich residential ego trips.. As far as skyscraper breakdown, Wikipedia provided a nice table. (no idea how up to date it is) Rank City ≥1,000 ft (305 m) ≥900 ft (274 m) ≥800 ft (244 m) ≥700 ft (213 m) ≥600 ft (183 m) ≥500 ft (152 m) ≥400 ft (122 m) Total 1 New York City 12 9 14 35 69 150 255 544 2 Chicago 6 2 6 8 27 68 101 218 3 Miami 0 0 1 9 9 32 36 87 4 San Francisco 1 0 3 2 4 13 32 55 5 Houston 1 2 0 7 8 18 22 53 6 Los Angeles 2 0 1 6 9 10 17 45 7 Seattle 0 1 0 3 3 12 23 42 8 Las Vegas 0 0 0 1 8 7 25 41 9 Atlanta 1 0 2 2 6 5 24 40 10 Philadelphia 1 2 1 3 1 6 18 32 Right now, Houstons office market cant really support a thousand footer and our residential market isnt hot enough for gazillionares to fork over investment for 1000'+ Condo high rises. My personal wishlist, build a beautiful 1200' building on Block 142. Then infill every other surface lot downtown with 10-15 story buildings-- same for midtown. Also, Dallas has a 1000'+ on the drawing board right now: https://www.papercitymag.com/real-estate/dallas-smart-district-tallest-high-tech-skyscrapers-amazon-headquarters/ And for my own City Pride, I'd like Houston to retain the taller skyline
  10. Purdueenginerd
    Im not sure how much faster it will go. Yeah the floor plates will be simpler but... theyre going awfully fast already haha.
  11. Purdueenginerd
    @ekdrm2d1 put this on my amazon wish list the other day. https://www.amazon.com/dp/B01DMDI5XU/?coliid=I1H95VI68DMOIF&colid=U35NVB7GTF0U&psc=1&ref_=lv_ov_lig_dp_it Hopefully my wife sees it in time for my birthday
  12. Purdueenginerd
    Im not a super big fan of light gage. Its superior to wood framing and more uniform. But Owners sometimes dont realize there are load bearing walls in the structure. From an architectural standpoint the floor plans more or less have to be uniform. Which is great for a hotel/apartments. Its get problematic and expensive when the floor plans change from floor to floor.
  13. Purdueenginerd
    Fair Warning: I dont know what happened, but the reason I dont necessarily think its shoring is because of the joist spacing. The joist spacing, shown above is about 18-24". Which would be more than enough to prevent steel deck failure associated with a lack of shoring. The roof joists are spanning about 30-40' (based off google earth) which isnt too unusual. During construction, the joists could be weaker for lateral torsional buckling, if their bottom and top flange are insufficiently braced. Other baseless speculation: If a joist was poorly connected, improperly connected, or designed poorly, it could facilitate a cascading failure. Lets imagine for a moment joist spacing is 24". And we have 4" of concrete. 4"/12"*1ft*150pcf. =50 lbs/ft^2 ( or PSF) of weight. The construction live load should and could be 50 PSF. Keep note of the construction live load, thats important. The total load theoretically would 100 PSF (plus self weight). On a single joist it would 100 PSF * 2 feet (or 24") = 200 lbs/ft(or PLF). Which means the load bearing wall at each joist is supporting 200 PLF* 30ft/2 =3000 lbs. Now, Imagine one of the joists and its respective connections to the load bearing wall failed. The next joist over, immediately picks up the load. So now the single 100 PSF * 3ft =300 lbs/ft. - a 50 percent increase in load on the next two joists over. Why did I bring up the Construction Live load? Because the roof is traditionally designed for a live load of 20 psf. -- This isnt a code discrepancy, Its just something a lot of contractors dont know about. So its plausible, that contractor may have inadvertently overloaded a connection, a single or multiple joists or some combination thereof. This could have precipitated the cascade. Structural steel Column Failure: Not Likely. Load bearing wall failure: Also not likely, but I have noticed that the studs are not currently braced for weak axis bending. Weak axis bending and strong axis bending are structural topics I wont get into unless you guys really want me to haha. Again, this isnt likely unless they used a much lighter gage steel at higher elevations (not unheard of).
  14. Purdueenginerd
    Additional comment: I went back and looked at a few photos from earlier in construction. I'm not totally convinced shoring is the issue here. Im still at my office, so when I go home, I'll get into my blind speculation.
  15. Purdueenginerd
    You just gave me a heart attack. I have a light gage building of similar height and construction that's topping out soonish. Let me just say, from the imagery I can see -- theres not a lot I can discern. But I will comment on the quote above, which involves shoring. Typically (though not always) steel decking can support a live load (ie, people), but can't support the wet, uncured concrete weight (dead load) without additional shoring. Typically for this style construction, the shoring is designed by a subconsultant that the contractor hires. Once the concrete cures then it effectively "adds" strength, or can self support without the shoring. The shoring is subsequently removed and construction proceeds. Getting into the weeds here, but this is the load tables both the contractor and their subs would have access to http://vulcraft.com/catalogs/412 (PDF warning) and if you go down to the load tables. You'll see every single deck has a table of its capacity... followed by another table of its "Maximum Construction Clear spans". For Example go to page 30, you'll see in some of those configurations, the deck can only span 5-6 feet before needing shoring (during construction). Obviously, I dont have their span tables or deck drawings so I cant comment on if their shoring was sufficient.. however looking at the photos. I dont see shoring on the level below the collapse. Thats not unheard of, but not that common. Generally you want to shore 2-3 levels. I also dont see shoring on the area to the right, though its not clear if that area was to receive concrete decking. Was the contractor dumb enough not to install shoring? -- I'd be genuinely surprised if that was the case... but contractors have surprised me in the past. Maybe more likely is that the shoring got bumped out of place (or improperly installed) which lead to collapse during concrete placement.
  16. Purdueenginerd
    Just shy of 1 million dollars for the contract amount seems quite low for what has been shown in renderings, IMO.
  17. Purdueenginerd
    Yep! @Luminare you got it. Think of it it like a concrete pump extension. Primary pump is a street level and it booms up to a certain point. In order to actually get the concrete where you want it to go. You could either have the main boom swinging around or just pump it to a secondary boom and get it where you need it to go.
  18. Purdueenginerd
    Thats a great photo!
  19. Purdueenginerd
    Disaster struck the moment they signed that contract!
  20. Purdueenginerd
    It is a bit unusual at this stage of the game. Unless theres another small structure going next to it, or soemthings going with the foundations (or, depending on the construction, the slab-on-grade). I did look up the firm. http://powerliftfoundation.com/ They seem to specialize in foundation repair. But they do perform some new construction it seems.
  21. Purdueenginerd
    Not sure actually. Do you see any of the brick veneer cracking? or any evidence of windows that have broken?
  22. Purdueenginerd
    Indeed! Good eye!
  23. Purdueenginerd
    I'll probably agree with @Luminare on this one. Consider me biased though. When you start getting that high, the stuctural engineering of items associated with wind loads get more and more challenging. A spire to me, is a structural member that has to be accounted for. That being said, I understand the Pro-Sears tower/Willis Tower position on occupied floor.
  24. Purdueenginerd
    Sorry @H-Town Man, I was off by a few months.
  25. Purdueenginerd
    I actually dont know how accurate Emporis. I'm not sure how they would have access to the contractors fees. for your second question. Yes. A lot of it can depend on interior and exterior finishes etc... a lot depends on finishes, difficulty of construction, and of course how fast the owner wants it. If the contractor has to throw a bunch of extra people on it to complete it quicker, then the owner is going to pay more.
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