Cicatrisation : the intervention

Talking about it is good, doing it is better....

Preparing the building site.

Plaster crack monitors are installed. These are nailed on each side to avoid any detachment from their support.
Some bracing and supports may be necessary during some phases of repairs.
Protection against inclement weather conditions should also be planned.

Clear up.

All instable or loose material must be removed until the support is perfectly clear and stable.
Any brick or cement filling must also be removed.

Preparing the support.

The preparation of the support is an important step to achieve a successful repair.
Small horizontal grooves should be cut to prevent the fresh soil from slipping.
The support is cleaned of any dust with compressed air before being humidified with a fine spray over several passages to avoid any surface flow which would erode some material.
It is preferable to humidify the support a day before the repair and again just before the repair.

Materials for the repair.

The material used to repair a rammed earth wall can be provided by an ancient wall after crushing and wetting. The local soil can also be used, which will have to be extracted well below the topsoil.

The soil must not contain any organic matter, humus or plant residue. It should also have a similar colour and particle size distribution to the original rammed earth wall to be repaired. If this is not the case, a more appropriate soil must be found. The soil is used in a slightly humid state, nearly dry.
The soil is rammed into the cavities with a pneumatic rammer or, failing that, a sledge hammer.
While ramming, precaution should be taken to not destabilise what has just been repaired and to make sure there is a good contact between the new repair and the wall.
After compaction, the rammed earth should sound dull.

Framework.

Framework is used to repair larger volumes.
It should be stiff and solidly fixed against the existing walls.

Drying shrinkage.

After complete drying, the binding of the repair to its support is verified by sounding the junction between the two.