Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

RE: IBC Allowable Service Loads on Embedded Bolts??

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Dan,

Table 1912.2 is for anchorage to plan concrete. 

I suggest that you embed the anchor rods within the reinforcing of the
concrete pier with sufficient embedment to developed the rod in tension
using Section 1913 (IBC). Shear is developed by bearing against the
concrete. Add shear keys or embedded angles to improve the shear capacity is
required. Design the reinforcing to around the anchor rods to prevent
breakout of the concrete.

Masonry anchorage is based on anchorage into masonry units.

Bill

-----Original Message-----
From: Daniel Boltz [mailto:dboltz(--nospam--at)1st.net]
Sent: Wednesday, September 15, 2004 11:05 AM
To: seaint(--nospam--at)seaint.org
Subject: IBC Allowable Service Loads on Embedded Bolts??


How is table 1912.2 of IBC 2000 used for anchor bolt design?  

I have a sign project that will have large base shear and tensile forces
induced into the anchor bolts.  I'm finding that a simple scoreboard will
require an outrageously high number of anchor bolts if I'm only allowed a
maximum tension force of 3650 lbs and shear force of 5300 lbs for a 1"
diameter anchor bolt.  How is this possible?

The same question could be applied to anchor bolts in masonry.  For an
in-plane load into a shear wall (based on NCMA TEK 12-3, ACI 530 Formulas
2-5 & 2-6), if the allowable shear load of 1900 lbs for a 3/4" diameter
anchor bolt is used, most precast slab / masonry wall systems would require
a large number of anchor bolts per shearwall.  There is a discrepency,
though.  In the masonry designers guide, example RCJ-03, pg. 17-251 shows
that the allowable shear in the bent bar is calculated according to ACI 318
for shear friction and the masonry shear strength is checked.  Why wouldn't
a bent bar connecting a hollow-core slab to a masonry shearwall need to
comply with the ACI formulas listed above?

A similar connection is shown in the Masonry Designer's Guide on Example
RCJ-11, pg. 17-318.  The strap shear of the steel is checked along with the
masonry bearing stress.  

I realize an anchor bolt and a bent piece of rebar are not the same, but the
force-transfer and connection requirement is the exact same.

Thanks.
--Dan  




________________________________________________________________
Sent via the WebMail system at 1st.net


 
                   

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ******** 


******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********