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            ANCHORS








             Where anchors fail to set within the maximum permitted number of turns,  Since the design bond strengths for adhesive anchors are often associated
             procedures to remove and replace the anchor are developed with the EOR.  with the use of specific drilling techniques (based on the resulting hole
             Where large numbers of anchors are being installed, the inspector may ob-  roughness), it is important that the specified hole drilling technique is used.
             serve the initial installations continuously, and thereafter perform periodic
             inspections as the installation proceeds.                Verification of hole cleaning procedures in accordance with the MPII is
                                                                      critical. Where holes are drilled and cleaned in advance of anchor
             ICC-ES acceptance criteria include a requirement for a length identification  installation, it must be verified that the holes are protected from intrusion
             letter code to be stamped on the ends of anchors recognized for multiple  of contaminants or moisture (e.g., rainwater) during the interim period,
             embedments (usually wedge anchors). This makes it possible for the special  or that the cleaning steps are performed immediately prior to anchor
             inspector to determine, in conjunction with knowledge of the specific an-  installation. Prior to anchor installation, hole depths must be verified to
             chor make, the embedment of these types of anchors after they have been  ensure the correct embedment and to determine, in the case of injection
             installed.                                               systems, that the correct amount of adhesive is dispensed into the hole.


             Verification of proper set is conducted according to the anchor type. Torque-  Injection adhesive systems have special requirements to ensure that the
             controlled expansion anchors such as wedge anchors and sleeve anchors are  adhesive injected is correctly metered and mixed. These usually include, for
             generally checked by application of torque with a calibrated torque wrench.  1 new cartridge, dispensing a quantity of adhesive from the mixing
             Drop-in anchors are checked by placing the setting tool into the anchor  nozzle prior to beginning injection of adhesive in the hole. The objective of
             body to verify full set prior to installation of the bolt or threaded rod.   adhesive injection is to avoid entrained air. For long holes and holes drilled
             Verification of proper set of screw anchors is performed during installation  horizontally or overhead, the MPII may specify special equipment such as
             by ensuring that the minimum torque resistance is achieved, that the   extension tubes, stoppers and end caps to achieve a void-free injection. The
             maximum torque is not exceeded, and that the anchor      presence of air bubbles in the adhesive may be detectable as a tendency of
             has achieved the required embedment.                                     the anchor element to spring back after being pushed
                                                                                      into the adhesive mass or a popping sound is heard as
               ADHESIVE ANCHORS                                                       air bubbles are displaced upward. Inspection of the
                                                                                      installed anchor includes verifying that the anchor
                      The special inspector must verify that the                      position is true (angle with respect to the concrete
                      installation is in accordance with the                          surface), that the anchor is secured against movement
                      requirements of the approved construction                       during the cure time, and that adhesive has not fouled
                      documents, applicable evaluation report                         the threads.
                      and the MPII, including verification of the location of the
                      anchor, edge distance and spacing requirements. Pre-  The inspector should verify that personnel performing adhesive anchor
                      installation inspection of adhesive anchors usually consists of  installation are experienced and qualified to use the specific adhesive
                      verification of anchor type, material, size and length, drilling  anchor system being employed. ACI 318-11 Appendix D requires that
                      method, drill bit type and size, hole cleaning procedures, and  certified adhesive anchor installers must perform all horizontal and
                      anchor installation and setting procedures. In addition, the   upwardly inclined installations of adhesive anchors that resist sustained
                      inspector must verify the expiration date of the adhesive and  tension.
                      the manner in which it has been stored.

                      Anchor elements (threaded rod, reinforcing bars, internally  CAMA Special Inspection Guidelines for Expansion and Adhesive Anchors,
                      threaded sleeves) must be inspected for the presence of   Copyright @ 2011 CAMA.
                      substances that might interfere with bond (e.g., dust, mud, oil)
                      and that the threads are undamaged and not fouled.
                      Reinforcing bars must be free of loose rust. In cases where the
                      concrete temperature may be higher or lower than normal
             room temperature, the concrete temperature in-situ must be verified prior
             to installation for conformance with the requirements of the MPII and to
             establish the cure time for the adhesive.
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