Anchors into existing concrete
Anchors into existing concrete
(OP)
I need tie down some wood-frame shearwalls to an existing slab. I found a program PDA-2, Powers Design Assist 2, which does an astounding job, but I can't believe the values. I also doubt my own values.
e.g.
I find that a 3/8" PowerStud 2 embedded 2" into 2500 psi cracked concrete, at 2.875" from an edge is good for 1400 lbs.
If you are familiar with PDA, please comment.
e.g.
I find that a 3/8" PowerStud 2 embedded 2" into 2500 psi cracked concrete, at 2.875" from an edge is good for 1400 lbs.
If you are familiar with PDA, please comment.






RE: Anchors into existing concrete
Note that SOME tables show ultimate loads with a tiny disclaimer leaving the Safety Factor up the design pro... I usally use 5:1
RE: Anchors into existing concrete
RE: Anchors into existing concrete
Hilti's values depended strongly on the actual concrete depth, width (distance of the hole) from the edge, psi of concrete, and depth of the new fastener. Pull out strength (resistance to up/down or sideways force at failure) determined which table you looked up values in.
RE: Anchors into existing concrete
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I have been called "A storehouse of worthless information" many times.
RE: Anchors into existing concrete
I like the Titen HD's because you just drill a hole through the sill plate and into the concrete and then screw the bolt into the concrete.
RE: Anchors into existing concrete
I will do a little exercising and report back. Thank you all. I appreciate your help.
RE: Anchors into existing concrete
I find that Simpson is OK enough for the yes-no question "Will this work?"; PDA2 is much more convenient for looking at a range of anchors. I wish that they had agreed exactly, and that the two lines were the same, but my original and main concern is now satisfied, that the program results are reasonable.
Thank you all very much.
RE: Anchors into existing concrete
The sw input is quite different, and caution is needed. One wants eff. h, the other wants embedment h, etc. The only thing I can't reconcile so far is that Simpson requires greater edge distance. I am glad to have both, and the price was right.
RE: Anchors into existing concrete
http://
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I have been called "A storehouse of worthless information" many times.
RE: Anchors into existing concrete
Don't forget to use LRFD load combinations before inputing loads if you are designing per ACI 318.
RE: Anchors into existing concrete
RE: Anchors into existing concrete
App. D doesn't quite fit for anchors on wood sill plates, and often isn't needed. Here is AWC's FAQ on the matter.
http:/
That links to the study done that shows how App. D relates.
This is now being adopted by codes and standards. The CA code states...
2305.1.4 Sill plate anchor bolts. [BSC, DSA-SS, DSA-SS/
CC and OSHPD 1, 2, 3 & 4J As specified in Section
1908.1.31 modifications to ACI 318, the allowable lateral
design strength for sill plate anchor bolts in shear parallel
to grain is permitted to be determined using the lateral
design value for a bolt attaching a wood sill plate to concrete,
as specified in AF &PA NDS Table 11 E, provided the
anchor bolts comply with all of the following:
1. The maximum anchor bolt diameter is 5/8 inches (16
mm).
2. The anchor bolt is embedded at least 7 inches (178
mm) into concrete.
3. The anchor bolt is located a minimum of 21/2 anchor
diameters from any concrete edge that is parallel to
the sill plate; and
4. The anchor bolt is located a minimum of 15 anchor
diameters from any concrete end that is perpendicular to the sill plate.
The next Wind and Seismic provisions for the NDS will have similar language, and I wouldn't be surprised if the next IBC is similar.