Arris

Summary

Arris - The term Arris is used to describe the right angled corner of a joint or crack between the slab top surface and the side of the joint/crack.

Technical Information

Where an unprotected arris is exposed to hard wheeled Materials Handling Equipment (MHE) traffic movements it is susceptible to damage. The arris edges can become spalled (rounding of the arris edge) creating a wider joint opening on the surface of the slab.

For large opening joints such as formed free movement joints this damage can become considerable and often effects the performance of the MHE using the floor. This can also happen where the 2 faces of a joint are not at the same level which exposes one side to greater impact loading than the other.

To avoid the breakdown of the arris at formed free movement joints a steel strip is often introduced, this type of joint is commonly referred to as an armoured joint.

When damage has occurred to a floor joint impacting the performance of the MHE then repair of the arris is essential. This involves in simple terms, cutting out a small section of slab parallel to joint and filling this section and joint with a suitable material.

The arris of induced movement joints especially those created with a saw are less susceptible to damage as they do not open as wide and there is no difference in level between the two sides of the joint.