Interpretation of drawing for casting

[Katarina12345]

Hello

The following instructions accompany a post that needs to be cast; I interpret it as the hole should be 500X500X600 and the concrete should fill 500X500X300.

What I'm wondering about is if I've understood the shape of the hole correctly if you dig straight edges? In the picture, it looks like the sides should slope inward, but it becomes difficult to understand what dimensions the bottom should have in that case?

I am also wondering about the materials; in the picture, it looks like you should cast a lump around the post, but at the same time, there are specified dimensions as mentioned earlier in mm. I'm also curious about the symbols. I understand that sand/soil is meant above the casting. But what are the materials represented by symbols further down in the soil? Concrete vs filling material?

Thanks in advance

 

[klaskarlsson]

Hi

The following instruction comes with a pole to be cast, and I interpret it as the hole should be 500X500X600 and that the concrete should fill 500X500X300.

What I'm wondering is if I have understood the shape of the hole correctly if you dig straight edges? In the picture, it looks like the sides are supposed to slope inward, but it would be difficult to understand what the bottom should measure if that is the case.

I'm also wondering about the materials, in the picture it looks like you're supposed to cast a lump around the pole, but at the same time, it says the specified measurements as mentioned earlier, mm. I'm also wondering about the symbols, I understand that it means sand/soil above the casting. But what are the materials that the symbols represent further down in the earth? Concrete/vs filling material?

Thanks in advance

What is the pole supposed to support? If it's for a deck, fence, plank, or similar, the exact measurements aren't as important. Those are likely minimum measurements to achieve a certain weight as well. Normally, you dig a "sufficiently large" hole where depth is most important, then fill with concrete and set the pole. It's quite tricky to get a different shape for the concrete than the hole unless you pre-cast the footing.

If you want it to be more resistant to frost heave, you can, in addition to making it deeper or insulating it, ensure the hole's sides slope in the opposite direction (i.e., the bottom diameter of the hole is larger). This way, the frost cannot lift the sides of the cone in the same way, as the concrete then slopes the "wrong" way so to speak. However, it's much trickier to dig that way, but your sketch/drawing shows the concrete's shape in that manner.

 

[Katarina12345]

What will the post carry?
So exact is not that important if, for example, it is for a deck, fence, plank, or similar.
It is probably minimum dimensions to support a certain weight too.
Normally, one digs a "sufficiently large" hole, where the depth is the most important, then fills it with concrete and sets down the post. It's quite tricky to get a different shape on the concrete than the hole's unless you pre-cast the plinth.

If you want it to be more resistant to frost heave, besides making it deeper or insulating, you can make sure that the sides of the hole slope in the opposite direction (i.e., the bottom diameter of the hole is larger). This is because the frost then cannot lift the sides of the cone in the same way, and the concrete slopes the "wrong" way, so to speak. However, it is much trickier to dig that way, but your sketch/drawing shows the shape of the concrete that way.

What will the post carry?
So exact is not that important if, for example, it is for a deck, fence, plank, or similar.
It is probably minimum dimensions to support a certain weight too.
Normally, one digs a "sufficiently large" hole, where the depth is the most important, then fills it with concrete and sets down the post. It's quite tricky to get a different shape on the concrete than the hole's unless you pre-cast the plinth.

If you want it to be more resistant to frost heave, besides making it deeper or insulating, you can make sure that the sides of the hole slope in the opposite direction (i.e., the bottom diameter of the hole is larger). This is because the frost then cannot lift the sides of the cone in the same way, and the concrete slopes the "wrong" way, so to speak. However, it is much trickier to dig that way, but your sketch/drawing shows the shape of the concrete that way.

Aha, okay, I understand, the post is part of a gymnastics bar that will stand in the community's playground. So the requirements for depth, width, etc. are strict to meet the regulations for these structures.