While ACI gives no limitations on maximum anchor diameter, for anchors beyond this dimension, the testing authority should decide if the tests described. 1 Jan Buy ACI QUALIFICATION OF POST-INSTALLED ADHESIVE ANCHORS IN CONCRETE AND COMMENTARY from SAI Global. ACI M A U.S. Customary version of this document (ACI ) is available at Qualification of Post-Installed Adhesive Anchors.
|Published (Last):||1 February 2015|
|PDF File Size:||16.40 Mb|
|ePub File Size:||15.79 Mb|
|Price:||Free* [*Free Regsitration Required]|
Pullout failures also occur for screw anchors only when they are deeply embedded. Deep embedments are often 35.4 to achieve because the friction of cutting a thread can exceed the torsional capacity of the screw shank and fail the steel in torsion.
The full and complete returned product will be accepted if returned within 60 days 35.4 receipt and in salable condition. First Name Last Name. To provide the mechanical interlock to the concrete, the screw anchor cuts a thread into the concrete during the installation process.
355.4-11 Qualification of Post-Installed Adhesive Anchors in Concrete and Commentary
Your message Submit Comment. These items are not eligible for return.
The ACI Code provisions are not mandatory unless adopted by the local building code for the given jurisdiction. Based partially on the Boston Big Dig tunnel accident, the adhesive anchor installer must be certified to install anchors in certain orientations and under certain load conditions.
This standard prescribes testing programs and evaluation requirements for post-installed adhesive anchors intended for use in concrete under the design provisions of ACI There are a wide variety of post-installed concrete anchors, and the newest post-installed anchor is the screw anchor. Research testing of screw anchors has shown that failure can occur in tension via three modes: Neal may be reached at nsanderson sgh.
The new structural building code ACI will be re-organized based on member type. This requirement is recognition by the ACI Code committee that adhesive anchor installation needed some oversight qualifications to achieve satisfactory installations, consistent with the written design requirements and anchor manufacturer installation instructions. In addition to installer certification, inspection is an important requirement required in ACI For post-installed mechanical anchors, anchors must be qualified to the criterion in the ACI Adhesive anchors loaded in shear behave similar to other post-installed and cast-in-place anchors, and, hence, existing design models and procedures could be used.
Appendix D will now formally be placed in the body of the Code as Chapter Certification was deemed an important component of adhesive anchor usage, on par with certified welders for welding key structural steel connections.
The Present State of the Industry Formal concrete anchorage design provisions first appeared in ACI as Appendix D, with applications limited to cast-in-place anchors and post-installed mechanical expansion anchors. Screw Anchors There are a wide variety of post-installed concrete anchors, and the newest post-installed anchor is the screw anchor. In reality, screw anchors have been around since the early s.
Pullout failures look very much like bond failures for adhesively bonded anchors. Undercutting of screw threads in concrete from Olsen, et. As of 15 Januarythe following will be required: Design Provisions Adhesive anchors were incorporated into ACI under the premise that the existing design models would be minimally affected. Although the design procedure for screw anchors has not been codified, they are gaining acceptance in building practice as a reliable fastening element Olsen, et.
The success, or failures, of adhesive anchors are highly dependent on the installer and the procedures employed to install the anchor. Qualification For post-installed mechanical anchors, anchors must be qualified to the criterion in the ACI For a listing of and access to all product errata, visit qci Errata page. So, what is the state of the anchoring industry and where do the codes go from here? Testing and assessment criteria are provided for various conditions of use, including seismic loading; sustained loading; aggressive environments; reduced and elevated temperatures; and for determining whether anchors are acceptable for use in uncracked concrete only, or acceptable for service both in cracked and uncracked concrete.
The next code cycle will contemplate further additions and layout reorganization. As of 15 Januarythe following actions were taken: Adhesive anchors were incorporated into ACI under the premise that the existing design models would be minimally affected. They are intended to carry direct tension, direct shear, or combinations of tension and shear loadings. Reference should be made to a paper by Hoermann-Gast for additional information. This includes the design provisions for bond strength and concrete breakout.
In the next Code cycle, screw anchors will be studied for inclusion. Formal concrete anchorage design provisions first appeared in ACI as Appendix D, with applications limited to cast-in-place anchors and post-installed mechanical expansion anchors. The creation of the threads in the concrete gives the screw anchor some advantage in cracked concrete where a small-narrow crack 3355.4 the 35.4 has only a minor reduction on tension capacity.
Criteria are provided for establishing the characteristic bond strength, reductions for adverse conditions, and the anchor category and associated job-site quality control requirements.
STRUCTURE magazine | Post-Installed Anchors
In ArticlesInSights Comments 0. Leave a Comment Click here to cancel reply. Any applicable errata are included with individual documents at the time of purchase.
Certification Based 355. on the Boston Big Dig tunnel accident, the adhesive anchor installer must be certified to install anchors in certain orientations and under certain load conditions. In 12 years, we have codified anchorage design procedures and developed anchor qualification standards that have greatly raised the reliability bar for anchors used in practical design conditions. In Figure 1, the undercutting of the threads in the concrete is illustrated.
Adhesive anchor design provisions for tension were the only provisions supplemented, necessitating new checks for concrete bond stress. This makes the use of screw anchors a single-use item; removing and reusing the screw anchor in the drilled hole is not advised because the cutting threads on the screw are worn and getting the screw threads into the original cut threads in the concrete is difficult.
Errata are not included for collections or sets of documents such as the ACI Collection. Aug, By Neal S.