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Re: SEISMIC ANCHORAGE

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Title: Re: SEISMIC ANCHORAGE

Changes to ICC Evaluation Service Reports of Concrete Anchors

Ladies and Gentlemen,
 
The purpose of this email is to summarize the changes that occurred to ICC evaluation services reports (available on the ICC-ES website)  January 1, 2007.  An ICC ES staff memos, explaining the changes, can be found here: http://www.icc-es.org/News/concrete_anchors_memo.pdf.  Please note that ICC-ES has applied these changes to all post-installed   concrete anchoring products, not only Hilti concrete anchors.

 
The California Building Standards Commission (CBSC) is planning to adopt the 2006 IBC starting January 1, 2008.  As of January 1, 2007, ICC-ES has reflected the new code requirements for post-installed anchors in their evaluation reports.  The changes to concrete anchor ICC ESR's (Evaluation Services Reports) affect the uses and recognition of concrete anchors under all building codes including the 1997 UBC, 2001 CBC, 2000 IBC, 2003 IBC, and the 2006 IBC.  Previous ESRs, based on allowable stress design (ASD) testing criteria (AC01, AC58 and AC106 - visit www.icc-es.org ), will be evaluated under new acceptance criteria (AC193 and AC308) addressing strength design, seismic considerations, and use of  post-installed anchors in cracked concrete applications.

 
**Other things to consider during the transition**
 
- Hilti anchors designed based on previous versions of the ICC Evaluation Services Reports are still valid and safe.  The changes to the ICC-ES evaluation reports for post-installed concrete anchors were not based on a safety or performance issue, however, the tests required to obtain an ICC approval for a concrete anchor have changed. 

 
 - The compliance with the code is ultimately decided by the engineer of record and the local building official.  Your local building official may choose to ignore the recent changes to ICC Evaluation Reports, however ICC-ES no longer supports the use of concrete anchor Evaluation Services Reports as they appeared on the ICC-ES website prior to January 1, 2007.

 
- All Hilti ICC-ES reports (based on legacy criteria -AC01, AC58, AC106) are still available for your reference on the Hilti website (see link below).

- OSHPD and DSA have indicated that they will continue to recognize ESRs issued under AC01 (expansion anchors and undercut anchors) and AC106 (concrete screw anchors) until the State of California formally adopts the 2006 IBC on January 1, 2008. At this time, we are not aware of any formal memorandum from either organization that will confirm this stance. Our recommendation would be that you contact OSHPD or DSA directly to determine their policy on the recent changes to ICC Evaluation Services Reports for concrete anchors.

 
**Summary of the Changes to ICC-ES Concrete Anchor Reports for Adhesives**
 
- ESRs issued in compliance with AC58 (adhesive/epoxy anchors) and AC106 (concrete screw anchors) will be recognized for use in seismic design categories A and B (no and low seismic areas) under the 2000 IBC and seismic zones 1 and 2A under the 1997UBC/2001 CBC.  These reports apply only to designs for uncracked concrete (as before).  These changes will severely limit the usage of these products in the Western United States.  As of January 1, 2008, these reports will be cancelled.  Only ASD design values are provided in these reports.

 
 
**How Can a Structural Engineer Determine Where a Product Can and Cannot Be Used?**
 
- To determine what acceptance criteria was used to develop an evaluation services report, consult section 6.0 (Evidence Submitted) in the body of the ESR.  The "Evidence Submitted" section may also be found in section 3.0 of older reports.  The building codes listed in section 1.0 (Evaluation Scope) of the report can be misleading.  This section lists all codes where the anchor can be used for concrete or masonry.  Thus a product listing the 2003 IBC in the Evaluation Scope Section 1.0 may only have IBC 2003 recognition for masonry.

 
- Currently, Hilti has three mechanical anchors approved under AC193 for use in all seismic design categories, in cracked and uncracked concrete:

 
** Reference Links**

Additional related information: http://www.us.hilti.com/strengthdesign
 
Hilti ICC-ES reports: http://www.us.hilti.com/holus/modules/techlib/teli_results.jsp?type=approvals-listings-reports&subtype=icbo

 
ICC-ES staff memo: http://www.icc-es.org/News/concrete_anchors_memo.pdf.
California Building Standards Commission (CBSC) timeline: http://www.bsc.ca.gov/prpsd_chngs/documents/2006/1-1-08_timeline_12-29-06.pdf

 
If you have any additional questions with regards to these recent code changes, please do not hesitate to contact our in house engineering staff at 918-252-6337 or HiltiTechEng(--nospam--at)hilti.com.  You may also email me or call me at 310-399-1052.

 
Regards,

Joe Cortese
Field Engineer – Los Angeles
Hilti North America
5400 S 122nd E Ave I Tulsa, OK 74146
P 310-399-1052 I F 918-461-7570
Joseph.Cortese(--nospam--at)hilti.com
www.us.hilti.com