So Why Are These Three Parameters So Important?

1) Moisture condition of concrete

When adhesives are installed into concrete holes and cure, they form a bond with the base material to transfer the load from the anchor element into the base material. The presence of water can affect adhesion to the base material. Anchors can be tested to varying moisture conditions, including dry concrete, water-saturated concrete, water-filled concrete, and submerged concrete.

2) Temperature ranges

Adhesive anchors cure because of a reaction between a hardener and resin. That reaction can be accelerated or delayed depending on the temperature of the base material. Temperature range impacts the adhesive anchors in four ways:

1. Adhesives are tested within a limited range of concrete temperatures at the time of installation. These temperatures are relevant to most installation conditions, but it’s important to verify that the concrete temperature at time at which your anchor is installed is within this range. Concrete temperature at the time of anchor installation can be influenced by geography, climate, and season.

2. The time required for the adhesive to cure (cure time) will be longer at colder concrete temperatures and shorter at higher concrete temperatures.

3. The time permitted to install an adhesive anchor (working time or gel time) will also vary with concrete temperature. Reference the Manufacturer’s Printed Installation Instructions (MPII) for working times.

4. Some products require conditioning to certain temperatures. For example, an ICC-ESR may state the adhesive cartridge must be conditioned to 70°F in base materials less than 70°F in order to achieve performance consistent with the tested data.

3) Drilling and hole cleaning

When a hole is drilled into concrete, the hole surface may vary from rough to smooth depending on the drilling method. Additionally, the hole is likely to be filled with concrete dust and debris from the drilling process.

Hole cleaning steps typically consist of blowing out the hole with compressed air, brushing the hole with a steel wire brush, and blowing out of the hole again. This cleaning method can vary depending on the adhesive product.