Austin

[alan auerbach]

I thought I knew two rules for pouring cement.

1. Don't pour on bare soil, but on a layer of compacted gravel or some such that will remain stable.
2. Try to keep the pour damp (for a few days to a week, depending on how fast it would otherwise dry), so the concrete will be stronger.

In the NW corner of the Texas operation there are two depressed (below-grade) segments. Cement was poured over a large area in the larger of the two -- directly on bare soil (though there's gravel at hand), and then apparently not dampened by the water trucks spraying everywhere else. Anybody know how come?

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[OneLapper]

One of the videos explained that what we are seeing there is a "mud" layer. Basically cement truck washout, very liquid in consistency, which soaks into the soil and solidifies.

With this process, I assume the compacted gravel is not needed.

 

[alan auerbach]

One of the videos explained that what we are seeing there is a "mud" layer. Basically cement truck washout, very liquid in consistency, which soaks into the soil and solidifies.

With this process, I assume the compacted gravel is not needed.

Thanks -- makes sense.

Also wondering why they need a crane that could reach the top of maybe a ten-story building -- when Tesla factories are just one story above grade (two in rare spots).

 

[Sirfun]

Thanks -- makes sense.

Also wondering why they need a crane that could reach the top of maybe a ten-story building -- when Tesla factories are just one story above grade (two in rare spots).

Those are big/wide buildings. They will have to reach out horizontally at about 30degree angle a long way, with a lot of weight. When you put that big stick out there at 250 feet it doesn't take much weight to topple the teeter totter. Cranes loose a lot of capacity as they lower from verticle.

 

[alan auerbach]

Those are big/wide buildings. They will have to reach out horizontally at about 30degree angle a long way, with a lot of weight. When you put that big stick out there at 250 feet it doesn't take much weight to topple the teeter totter. Cranes loose a lot of capacity as they lower from verticle.

Must be so; thanks. (I assumed it would be more efficient for smaller cranes to drive the components to the far side.)

 

[alan auerbach]

Texas still prohibits direct (not thru a dealer) vehicle sales?

If so, good for you legislators! Do protect your dealers by not giving in.

(We assume that, for ease of distribution, the first area to get CT deliveries would be Texas. So if Texas registrations are hampered, those of us outside Texas won't mind.)

 

[alan auerbach]

The drone-camera operators show us the ground preparation (thanks guys). But there must be unseen preparations on the go -- prefab building components, stamping and other machinery, battery testing, robot programming, production layouts, and others I can't even think of. Anyone have a handle on these other preparations?

 

[RonM]

Give me a minute to fire up my mosquito ?drone and fly it into the Fremont ? research site and dig up that information. Getting close...WOO.. There’s Elon with a big ??can of bug spray! Mosquito One to home base. “I’ve been fogged, I repeat Mosquito One going down! Do ? not, do ?not send in any assistance....ALL IS LOST” ???

 

[Ehninger1212]

The drone-camera operators show us the ground preparation (thanks guys). But there must be unseen preparations on the go -- prefab building components, stamping and other machinery, battery testing, robot programming, production layouts, and others I can't even think of. Anyone have a handle on these other preparations?

Most of these preparations would be internal, so unless there is a leak we wont see them yet. However, from an architectural perspective these things should have been coordinated with vendors MONTHS ago, like before construction even started. These vendors need an adequate lead time and the prefab building vendor should have been involved from the beginning.

Also.. all vendors probably sign NDA's.

 

[Sirfun]

Most of these preparations would be internal, so unless there is a leak we wont see them yet. However, from an architectural perspective these things should have been coordinated with vendors MONTHS ago, like before construction even started. These vendors need an adequate lead time and the prefab building vendor should have been involved from the beginning.

Also.. all vendors probably sign NDA's.

As I'm sure you are very aware of, but maybe not the average person on this forum. That's why we're seeing the 6 triple-wide trailers, with about 40 vehicles parked in front of them on the drone videos. All the different contractors are drawing up & coordinating their plans on how that great big factory is going to get built. Also that is why they are doing a lot of the ground work in other areas besides where the building footprint is. They are going to need a lot of areas to maybe do prefab and store all the building supplies with parking for all the construction crews. Then again, they could build this in phases over a longer timeframe, more like Giga Nevada, and use the building footprint for parking and staging areas.

 

[Crissa]

Yeah, that grey stuff they were pounding into the site was the ground prep. They also had trucks bringing in stuff to do the geopier stuff, taking out the soil and putting in some gravel mixture to compact into the pilings.

The reason you put a layer of gravel under concrete is to make sure that before it hardens, it doesn't leach into the surrounding soil (or vice versa) and change the ratio of ingredients in your slurry. A slight change will change the end properties and can create pathways for infiltration, cracking, etc. The smoother the surface that you create, the less pathways, and the more uniform, the easier it is to control the mixture.

Of course, I have no idea the ratios, I've only done the labor parts of this. ^-^

-Crissa

 

[alan auerbach]

Yeah, that grey stuff they were pounding into the site was the ground prep. They also had trucks bringing in stuff to do the geopier stuff, taking out the soil and putting in some gravel mixture to compact into the pilings.

The reason you put a layer of gravel under concrete is to make sure that before it hardens, it doesn't leach into the surrounding soil (or vice versa) and change the ratio of ingredients in your slurry. A slight change will change the end properties and can create pathways for infiltration, cracking, etc. The smoother the surface that you create, the less pathways, and the more uniform, the easier it is to control the mixture.

Of course, I have no idea the ratios, I've only done the labor parts of this. ^-^

-Crissa

If you haven't been watching the drone camera work, you'll be happy to know that a major milestone just occurred. The steel building-framework has begun! (So far limited to the geopiers, but next should be the laying of concrete, then the huge buildings, all in short order.)