Punch tools for R-FF1 and R-FFS frame fixings – installation in aerated concrete

How do you obtain the highest load capacities for frame fixings in aerated concrete?

Question: How do you obtain high load capacities for frame fixings in soft aerated concrete substrates? Answer: using the R-FF1-PT-II-10 and R-FFS-PT-II-10 punch tools.

Nowadays, aerated (or cellular) concrete is a popular construction material. The material owes its key features to the porous structure. On the one hand, the evenly distributed air pores provide excellent thermal insulation, and on the other hand they make the substrate brittle as well as susceptible to mechanical damage, and consequently easy to process. 

There is an important reason why punch tools are recommended for aerated concrete. Conventional drilling removes material from the unit, weakening its structure. Making holes using a punch tool, on the other hand, results in internal “compacting” of the material without removing any of it, which in turn has a positive effect on the frame fixing embedment strength. 

To sum up: setting tools make it easy to install fixings in soft substrates such as aerated concrete, and thus to achieve the maximum load capacities for solutions of this type.

The R-FF1-PT-II-10 and R-FFS-PT-II-10 punch tools were designed for the installation of the following:

• frame fixings with a long expansion zone R-FF1-K (with flange),
• frame fixings with a long expansion zone R-FF1-L (without flange),
• frame fixings with a short expansion zone R-FFS.

How to install frame fixings using a punch tool?

First, drive the setting tool with a hammer (e.g. RT-HAM) into the aerated concrete substrate to the appropriate depth, and subsequently install the frame fixing in the hole thus made.

Installation of the R-FFS frame fixing with a short expansion zone using the punch tool:

 
Installation of the R-FF1 frame fixing with a long expansion zone using the punch tool:

Why is it worth using a punch tool to install frame fixings in aerated concrete?

Using the punch tool, you obtain a hole surrounded by reinforced, compressed and compacted aerated concrete, which translates into high pull-out load capacities. Punch tools used with the R-FF1 and R-FFS frame fixings usually make it possible to obtain higher load capacities than those achieved with the standard method, as confirmed by European Technical Assessments ETA-12/0398 (R-FF1) and ETA-18/0818 (R-FFS).

This property turns out to be particularly useful in situations where the contractor or designer expect to achieve high load-bearing capacities with a relatively weak substrate, such as cellular concrete.

The punch tool also eliminates the need to drill holes beforehand in the substrate, thus minimising the amount of noise and dust generated, and making the work much more comfortable and cleaner compared to standard drilling.

Load capacities obtained using a punch tool for frame fixings

Load capacities of the R-FF1-N-10 frame fixing specified in the ETA for the following aerated concrete classes:

• AAC 2 cellular concrete, characteristic load capacity 0.4 kN
• AAC 4 cellular concrete, characteristic load capacity 1.2 kN
• AAC 5 cellular concrete, characteristic load capacity 1.5 kN

Load capacities of the R-FFS-N-10 frame fixing specified in the ETA for the following aerated concrete classes:

• AAC 4 cellular concrete, characteristic load capacity 1.5 kN
• AAC 5 cellular concrete, characteristic load capacity 1.5 kN