Can the foundation be much shallower if the anchor bolts of the tower use small-sized bolts? !
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For a tower, large foundation bolts are used, and the required burial depth is also deep. If small foot bolts are used in larger quantities, the required burial depth would be much shallower, right? Please give me some advice. .
Yes, the large bolts will be buried deeper.
Small-sized bolts can be buried at a shallower depth, but the overall weight still needs to be taken into account for the foundation; relying solely on thin bolts to increase the diameter of the foundation and skirt often proves to be counterproductive.
Talk to the civil engineering team; generally, the embedment depth of anchor bolts is proportional to their diameter
Regarding the issue of the embedment depth of the foundation bolts for tower equipment, I have discussed it with the structural engineering team; they are indeed able to calculate this depth. However, the values they obtain are usually on the low side, and in most cases they choose the appropriate value based on manuals (in other words, it’s a multiple of the bolt diameter – this multiple varies depending on the seismic intensity and the material used; values such as 20d, 25d, 30d, 36d, etc., are used). So, what the original poster means is that since the bolt diameter is larger, the required embedment depth is also greater. Understanding it from this perspective makes sense, but the calculation of the bolt diameter for tower equipment is based on combined bending moments (seismic bending moments, wind bending moments, eccentric bending moments). Moreover, the number of bolts is usually chosen based on the diameter of the equipment; simply increasing the number of bolts while reducing their diameter is not necessarily a good approach. As an extra note, the higher the strength of the bolt, the greater the required embedding depth.
Okay, thank you. Some devices have a small diameter, so using large bolts would be a waste; moreover, the foundation construction is quite deep. Small bolts still have advantages.
The device is small, so the calculations probably won’t require a large margin
The bolt spacing factor also needs to be taken into account: larger bolts with a smaller number result in greater spacing, while smaller bolts with a larger number lead to smaller spacing.