Adhesive Anchors Application Guidelines

Core Drilled Holes

The performance values for Epoxy-Tie Adhesive formulations (SET, ET, or ETF), Acrylic Tie Adhesive (AT) and Vinylester Glass Capsule Adhesive (VGC) are based upon testing of anchors installed in holes drilled with a rotary hammer and carbide tipped drill bits.

Additional tension tests were conducted to establish the performance values for anchors installed with Epoxy-Tie Adhesive formulations and Acrylic Tie Adhesive in holes drilled with a diamond core bit (Note that the diameter of the diamond core bit corresponded to that of the recommended carbide tipped drill bit). A comparison of these results has shown no reduction in the published allowable tension load values for the SET, ET, ETF and AT Adhesives. The same conclusions also apply to the published allowable shear load values.

Oversized Holes

The performance values listed in this catalog for Epoxy-Tie Adhesive formulations (SET, ET, or ETF), Acrylic Tie Adhesive (AT) and Vinylester Glass Capsule Adhesive (VGC) are based upon testing of anchors installed in holes drilled with carbide tipped drill bits either 1/16 inch or 1/8 inch greater than the nominal diameter of the insert (see product load tables for product-specific drill bit diameters). In order to qualify Simpson adhesives for installation in holes with diameters larger than those listed in the load tables, static tension load tests were performed on Acrylic-Tie and Epoxy-Tie products.

A comparison of these results has shown no reduction in the published allowable tension load values for the SET, ET and ETF Adhesives for installation in holes drilled with carbide tipped drill bits up to 150% of the recommended drill bit diameter (Reference the table below). The same conclusions also apply to the published allowable shear load values.

A comparison of these results has shown no reduction in the published allowable tension load values for the AT Adhesive for installation of 3/8 inch through 7/8 inch diameter inserts in holes drilled with carbide tipped drill bits up to 1/8 inch over the nominal diameter of the insert. In the case of a 1 inch diameter insert installed in holes drilled using 1-1/8 inch diameter carbide tipped drill bit, a load adjustment factor of 0.75 applies to the allowable tension values based on bond strength. There is no reduction in the allowable shear load value. Drill bit diameters outside the acceptable range (reference the table below) are not recommended.

Installation in Damp, Wet and Submerged Environments

The performance values for Epoxy-Tie Adhesive formulations (SET, ET, or ETF), Acrylic Tie Adhesive (AT) and Vinylester Glass Capsule Adhesive (VGC) are based upon testing of anchors installed in dry holes.

Additional tension tests were conducted to establish the performance values for anchors installed in damp (SET, ET, ETF and AT), wet (SET and AT) and submerged (SET, ET, and AT) environments.

A damp hole, as defined in ASTM E1512 and referenced in ICC ES AC58, is a drilled hole which has been properly drilled, cleaned and then filled with standing water for seven days. After seven days, the standing water is blown out of the hole with compressed air and the adhesive anchor is installed. Results from these tests have shown no reduction in the published allowable tension values for the SET, ET, ETF and AT Adhesives. The same conclusions also apply to the published allowable shear load values.

A wet hole is defined similarly to a damp hole; however, the standing water is not blown out of the hole. Instead, the adhesive is injected directly into the water filled hole and the insert is installed. Results from these tests have shown no reduction in the published allowable tension values for the SET and AT Adhesives. The same conclusions also apply to the published allowable shear load values.

A submerged hole is similar to a wet hole with one major exception - in addition to standing water within the hole; water also completely covers the surface of the base material as well. Note that drilling debris and sludge should be removed from the drilled hole prior to installation. There are no specific test standards (ASTM, ICC ES, etc.) that address this condition. Results from these tests have shown that a load adjustment factor of 0.60 applies to the allowable tension (and shear) values based on bond strength for the SET, ET and AT Adhesives.

Installation in Green Concrete

Concrete is considered green if it has cured less than 28 days. Adhesive anchors should not be installed in concrete which is less than 7 days old. The anchor should not be loaded prior to full cure of the adhesive. The performance of adhesive anchors installed in green concrete which are loaded prior to full cure of the concrete, should be based on the actual compressive strength of the concrete at the time the load was applied.

Installation in Improperly Prepared Holes

Adhesive anchors should be installed in accordance with the published product specific instructions to ensure optimum performance. One step in the installation sequence in particular is important - proper cleaning of the drilled hole. Prior to injection of adhesive into the drilled hole, dust should be removed from the drilled holes using oil free compressed air and a nylon brush. In the case of the SET Adhesive, testing was conducted on anchors intentionally misinstalled where the drilled hole was blown out with compressed air only or when the holes were neither blown out nor brushed. Results from these tests have shown a 3% reduction in the published allowable tension values when the drilled hole is blown out only. A 37% reduction in the published allowable tension load values for the when the drilled hole is neither blown out nor brushed. In these tests, the drilled hole depth was increased from the required embedment depth to prevent the dust in the drilled hole from interfering with the required embedment depth.

Elevated In-Service Temperature

The performance of all adhesive anchors is affected by elevated base material temperature. The In-Service Temperature Sensitivity table provided for each adhesive provides the information necessary to apply the appropriate load adjustment factor to either the allowable tension based on bond strength or allowable shear based on concrete edge distance based for a given base material temperature. While there is no commonly used method to determine the exact load adjustment factor, there are a few guidelines to keep in mind when designing an anchor that will be subject to elevated base material temperature. In any case, the final decision must be made by a qualified design professional using sound engineering judgment:

• When designing an anchor connection to resist wind and/or seismic forces only, the effect of fire (elevated temperature) may be disregarded.
• The base material temperature represents the average internal temperature and hence, the temperature along the entire bonded length of the anchor.
• The effects of elevated temperature may be temporary.
• If the in-service temperature of the base material is elevated such that a load adjustment factor is applicable, but over time the temperature is reduced to a temperature below which a load adjustment factor is applicable, the full allowable load based on bond strength is still applicable. This is applicable provided that the degradation temperature of the adhesive (350° F for SET, ET, ETF and AT) has not been reached.