Skip to content

Unit: Concrete grinding

LMFFL2107A: Select, operate and maintain grinding equipment

Section 1: Principles of grinding

Concrete surface profiles

Image for slide 1
Audio for slide 1 (mp3 |6|KB)
In the previous lesson we looked at the range of machines used to remove the top layers of a concrete floor.

Each type of machine has its own mechanical action, which can often be described in more precise terms.

Different machines also produce different surface profiles.

hearing icon
Image for slide 2
Audio for slide 2 (mp3 |6|KB)
The International Concrete Repair Institute has developed a set of guidelines for assessing a concrete surface profile (CSP), ranging from CSP 1 (nearly flat) to CSP 9 (very rough).

Follow the link below to see an information page from Floorex showing a photo for each profile and giving an example of the processes used to achieve it.

Surface profile guide

hearing icon
Image for slide 3
Audio for slide 3 (mp3 |6|KB)

Surface treatments and CSPs

Below are the mechanical actions and other forms of treatment used to remove surface contaminants from concrete.

Also shown are the CSP numbers that typically apply to these treatments.

hearing icon
Image for slide 4
Audio for slide 4 (mp3 |6|KB)
Chemical reactions are produced when detergents or acids are used to remove surface contaminants.

Most chemical washes don't have any effect on the CSP.

However, there are various cautions that apply, especially in neutralising and hosing off the acid wash with water.

You must also ensure that the slab is allowed to dry out to a relative humidity level that's safe for installing a floor covering.

For more details, see 'Preparing concrete substrates' (in Subfloor coatings and toppings).

hearing icon
Image for slide 5
Audio for slide 5 (mp3 |6|KB)
Abrasion is used by grinders to erode the surface through a rubbing action.

In many cases, grinders are able to smooth and level a floor to a standard that is sufficient for laying a resilient floor covering directly on top.

They can achieve a surface profile of CSP 1 to 2.

hearing icon
Image for slide 6
Audio for slide 6 (mp3 |6|KB)
Pulverization is the removal of material through blasting with small particles, such as sand or steel shot.

This is the process used by sand blasters and shot blasters, with wide ranging profiles of CSP 2 to 8.

hearing icon
Image for slide 7
Audio for slide 7 (mp3 |6|KB)
Impact is used by scarifiers and scabblers to break up the concrete surface by repeatedly hitting it with hardened cutters or bits.

This mechanical action has the most potential to damage the concrete, but the profile can be varied with different attachments, ranging from CSP 4 to 9.

hearing icon

Learning activity

Audio 8 (mp3 |6|KB)

Let's go back to the Surface profile guide we looked at earlier and examine the photos in more detail.

From what you know about the different processes used to create these CSPs, what characteristics can you see that makes each one distinctive?

In particular, what is it about the surface texture of the following processes that makes that type of concrete removal distinctive?

  • Grinding - CSP 2

  • Shotblasting - CSP 3 and 5

  • Scarifying - CSP 4, 6 and 9.
hearing icon