ACI 318-08 Section D6.2.2

[palves]

I'm currently using a computer program to analyze cast-in anchor groups and need some clarification. When I calculate Vb from this section I am using Le=hef since my anchor is not a torque controlled expansion anchor as the 2nd provision for Le states. However, the computer program has a slightly different number for Vb and the difference seems to be in their use of the line "in no case shall Le exceed 8*da", even though it appears to me that this ONLY applies to the 2nd case. Or does it? Does anybody know if this sentence applies to BOTH provisions for Le, in which case it would supercede my Le=hef. Thanks.

 

[KBVT]

I've always applied the 8do max to all cases.

 

[KBVT]

Check out example 34.4 in the 2005 PCA notes. The example is for a cast-in anchor and they utilize the 8do as the controlling case since the embedment depth exceeds 8 times the anchor diameter.

 

[Lion06]

I don't have the '08 version in front of me, but I wrote a spreadsheet using the '05 version and I have 8d0 as the limit for Le. I'll check out '05 and '08. What in the text makes you believe that the limitation is meant for torque controlled anchors only? If you have a 1/4" diameter anchor with 25" embed, you wouldn't want to use Le=25" would you? I know I wouldn't.

 

[Lion06]

I'm not reading anything in D6.2.2 to lead me to believe that the Le<=8da requirement applied to torque controlled anchors only. What do you read that makes you believe that?

 

[palves]

The layout is what made me think Le<=8da applied only to torque controlled anchors. It was directly included with the Le=2da paragaraph and not separated to imply that it also applied to the Le=hef paragraph above.

 

[KBVT]

"in no case shall le exceed 8do."

The language seems pretty clear to me, it applies to all anchors

 

[palves]

I agree the language is clear, but I thought what it referred to wasn't. I find that the codes often lay things out in ways that aren't 100% clear and open to interpretation depeding in how one reads it. The example you (KBVT) gave me from the PCA Notes is exactly what I'm looking for when trying to clarify what their language refers to. Thanks for that.