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Bolt Design for Ledger Beam 3
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MiketheEngineer
Structural
Masonry wall might be controlling?? But 500 lbs actaully doesn't seem unreasonable - but haven't checked.
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No, it doesn't work that way. Problem is, I don't have the latest masonry code. The 1010 pounds is the minimum value of all possible failure modes of the bolt in the wood ledger by itself.
There is a separate check for failure mode in the masonry. If the masonry is uninspected, the allowable stress is reduced by half but that is not applied to the 1010 pounds wood value...it is applied to the bolt value in masonry.
Is this regular solid-grouted CMU at least 8" wide? Also, the bolt needs to be 6" into masonry.
There is a separate check for failure mode in the masonry. If the masonry is uninspected, the allowable stress is reduced by half but that is not applied to the 1010 pounds wood value...it is applied to the bolt value in masonry.
Is this regular solid-grouted CMU at least 8" wide? Also, the bolt needs to be 6" into masonry.
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@Cap4000 : Ref: ACI 530-05, Section 2.1.4.2.3 - Allowable Stress Design of masonry
The allowable load in shear primarily depends on the strength of masonry, edge distance of anchor from
top of the masonry, and area of anchor.
Assuming min. strength of masonry as 1500 psi and fy for steel as 36000 psi, I get the following values:
edge dist. from top of masonry ----- Allowable load in shear
10.5" ---------------------------------------------- 1917 lbs.
8" -------------------------------------------------- 1412 lbs
6" -------------------------------------------------- 1009 lbs
4" --------------------------------------------------- 605 lbs
3" -------------------------------------------------- 403 lbs
The minimum effective embedment length of the headed and bent-bar anchor bolt shall be 4 bolt diameters, but not less than 2".
The allowable load in shear primarily depends on the strength of masonry, edge distance of anchor from
top of the masonry, and area of anchor.
Assuming min. strength of masonry as 1500 psi and fy for steel as 36000 psi, I get the following values:
edge dist. from top of masonry ----- Allowable load in shear
10.5" ---------------------------------------------- 1917 lbs.
8" -------------------------------------------------- 1412 lbs
6" -------------------------------------------------- 1009 lbs
4" --------------------------------------------------- 605 lbs
3" -------------------------------------------------- 403 lbs
The minimum effective embedment length of the headed and bent-bar anchor bolt shall be 4 bolt diameters, but not less than 2".
MiketheEngineer
Structural
Most large anchor suppliers, Hilti, Simpson, Fastenal, etc can supply you tables that fit these exact requirements.
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The American Wood Council has an online calculator.
I think it's appropriate to use concrete as your main member type, although I don't what their assumption is for dowel bearing strength in the masonry. The only reference I've ever found is the 1997 NDS, Table 8.2E, which gave a dowel bearing strength of 6000 psi for >= 2000 psi concrete or for masonry. It probably doesn't matter, as Mode IIIs will likely control.
I think it's appropriate to use concrete as your main member type, although I don't what their assumption is for dowel bearing strength in the masonry. The only reference I've ever found is the 1997 NDS, Table 8.2E, which gave a dowel bearing strength of 6000 psi for >= 2000 psi concrete or for masonry. It probably doesn't matter, as Mode IIIs will likely control.
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