There are special fasteners for concrete, brick, and block that are used for fastening items or fixtures to each base material. All the different types of fasteners that are designed for use in concrete and masonry are simple to use and easy to work with. No special tools are required other than a hammer, wrench and hammer drill. Determining which fastener to use from the wide selection available can be accomplished with just a bit of knowledge and experience.
Before starting your next project that requires anchoring to concrete or masonry, consider the following questions:
1. What is the base material? Some anchors can only be used in concrete while others can be used in both concrete and masonry base material.
2. What will be fastened to the concrete or masonry? Is it a small, lightweight application or is it a heavy load?
3. Will I need a female type anchor or male type anchor? Female anchors allow for bolting and unbolting of the item while male concrete anchors are used for more permanent installations.
4. Do I have a hammer drill? The use of a hammer drill in the installation of concrete or masonry anchors is essential.
5. Are aesthetics important? Some anchors stick out from the base material and others will blend in.
Here is a table showing different types of concrete and masonry fasteners and the base material they are best suited for:
There are two basic forces acting on a fastener that is embedded into concrete or masonry. One force will be trying to pull the anchor out of the concrete/masonry. The second force is a downward force trying to shear the fastener. Each concrete or masonry fastener has a holding value associated with it which is based on each manufacturer's testing.
Other considerations that must be followed include:
1. Concrete and masonry anchors' holding values are dependent on the quality of the base material in which they are embedded.
2. Mechanical concrete and masonry fasteners should be used in static type loading applications. A static load is a load that does not move and exerts a constant force.
3. Dynamic or impact loads should not be applied with mechanical type anchors. A dynamic load is a load that constantly is in movement, like a flag on a flagpole. Impact loading applications are ones that on occasion get hit with a heavy load, like a press.
Concrete and masonry fasteners can be male or female type anchors. Female type anchors are used in cases where a bolt is inserted into them and are removable after installation. Male type anchors are usually a permanent fixing and are not removable.
|Type of Concrete Fastener||Suitable Base Material||Indoor/Outdoor Use|
|Tapcon® Concrete Screws||Concrete
|Hammer Drive Anchors||Concrete||Zamac/Zinc- indoor
All concrete & masonry fasteners require a hole to first be drilled into the base material. The use of a hammer drill is essential to:
1) make the job much easier
2) drill a quality hole
3) ensure a longer bit life.
The male type anchors allow for drilling through the fixture while it is in place while female anchors require that the hole is spotted and then drilled. The spotting of the hole requires that the fixture is put in place, the base material marked where the hole needs to be drilled, the fixture removed, the hole drilled and the fixture put back in place then the bolt can be inserted through the fixture and into the concrete anchor.
These anchors should be spaced a minimum of 10 anchors from each other and at least 5 anchor diameters away from any unsupported edge. Any closer spacing will decrease holding values and in some cases could make the holding values non-existent.
Hole size is also critical for applications using these anchors. Holding values are derived from friction between the anchor and the wall of the hole in the base material. Matching the bit to the anchor is essential. Male anchor hole size is equal to the diameter of the anchor being used while the hole for a female anchor will be larger than the designated diameter of the anchor. Each female anchor hole size is different because each outside diameter is different.
After drilling a hole, clean out any debris and dust remaining in the hole after drilling. This step is essential to ensure proper holding values of an anchor. A wire brush, vacuum or compressed air works well when cleaning out the hole. It is also important to wear eye and ear protection when installing any type of concrete or masonry fastener.
All of these tips, along with experience, will help ensure that the installation of a concrete or masonry fastener goes smoothly.
As with any anchoring project, it is important to keep safety in mind and follow instructions carefully. Always remember to wear safety goggles, handle all tools with extra care and follow all technical specifications. This article is meant to serve only as a basic explanation of concrete fasteners. Always refer to manufacturer's instructions or consult a contracting expert during any anchoring project.