SpaceX foundation slab pulverised 11

[saikee119]

The above photo was from a youtube video showing the reinforced concrete supporting structure of the SpaceX rocket before and after the yesterday's launch when it exploded 4 minutes into the flight.

It appears the RC slab was flush as one level prior to the launch but now has the ground beams exposed. The video also claimed there were concrete fragments flying all over the place as shrapnel damaging some fuel and water tanks.

There seem to be at least the following issues in play:-

(1) The "disappeared" reinforced concrete slab was totally unsuitable for its purpose. I do not know if it was reinforced or not but it would have been criminal if it wasn't.
(2) The reinforced concrete columns and ground beams show little damage. This would suggest the reinforced concrete in adequate dimension could be the suitable material for the structure including the slab if adequately shield from the high temperature heat.
(3) Had any of the RC column or ground beam failed during the last launch the supporting structure might not have remained static then the rocket could have shot off at an angle other than vertically upward. Consequently a huge disaster could occur if the rocket hit the population with the amount of fuel it carried.

 

[IRstuff]

I don't know how easy it is to get a 'blast diverter' or a water cooling system; I think that's what he requires.

Musk knew that; he simply decided to "go fast and break things." Unfortunately, not only did he break his own things, he broke a bunch of other people's things as well, such as the vehicle that famously gets clobbered in the videos as well as a wildfire in a state park, etc.

https://www.expressnews.com/busines...ofit-s-survey-spacex-launch-site-17924836.php

https://www.tpr.org/environment/202...plosion-caused-extensive-environmental-damage

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[phamENG]

"go fast and break things."

Yeah...tech start up mentality works well for tech start ups...less so for aerospace...

 

[kjoiner]

Hello,

I've seen several videos regarding NASAs water system and flame trench. One topic that always comes up is mitigation of accoustic damage that can occur to a launch vehicle. The sound waves bounce off the surface back up to the rocket and can cause damage. The water deluge system seems to not only handle the thermal issues but the water flow and steam created also reduce the sound level. I know SpaceX wanted to have a faster schedule but how did they think a rocket with twice the thrust of a Saturn V would not have issues?

The launch pad was not only pulverized, but debris and other factors appear to have taken out a few engines right on the launch pad.

 

[gte447f]

I am trying to understand the dimensional scale of the structure in the photo posted above. Is that a one-story building next to the pylon structure on the right side of the photo and is that a stairway with approximately 3 stories visible inside the pylon structure on the left side of the photo? That's what it looks like to me, and if so, then the scale of that concrete grade beam that got obliterated is quite massive, maybe something like 10 feet thick/deep. Am I seeing that correctly?

 

[Murph 9000]

I couldn't easily find a reliable looking source for the dimensions. That certainly does look like a permanent access stair on the left. I count 4 semi-enclosed levels, and 2 open levels below the ring structure. I roughly estimate about 3m / 10ft per level, so maybe around 18m / 60ft from ground to the underside of the ring. That's a very rough guesstimate. Possibly as much as about 100ft to the top of the ring; the levels in the stair look quite tall, so maybe more than 10ft.

 

[dold]

Looks like the base is ~75' tall (ignoring any sort of errors from this perspective). Starship including booster is 394' tall and 29.5' wide.

 

[thebard3]

Some details are coming out. Apparently 3 engines failed to reach full thrust and were shut down on the pad. This loss of thrust ~9% contributed to the rocket's long delay to leave the pad which certainly contributed to the failure of the Fondag (about 8 seconds instead of 2.5 seconds). SpaceX has proposed the possibility that the downward thrust was sufficient to force the Fondag downward by compacting the sandy material below which contributed to the total failure of the blast pad. Supposing both are true, then the absence of either occurrence would certainly have had less consequence.

Brad Waybright

The more you know, the more you know you don't know.

 

[dold]

SpaceX has proposed the possibility that the downward thrust was sufficient to force the Fondag downward by compacting the sandy material below which contributed to the total failure of the blast pad.

That's a pretty interesting take. It would be like an absolutely massive vibratory compactor affecting the soil/sand. Certainly these effects would fall well outside the realm of normal geotechnical engineering scope - i.e., extreme dynamic loading from the largest rocket ever (unless NASA got really into the weeds during the Apollo program, which seems reasonable).

Fortunately it looks like the actual foundation of the launch stand is supported by some gargantuan piles. I'd eyeball those at ~8-10ft diameter? (I had to make another crappy bluebeam markup...)

Here are some cool pics of the construction from this youtube video: