In scaffolding, a raker is an inclined scaffold tube having a bearing upon the ground or an adjacent structure. Raker support and push the scaffold onto the building. This system takes up space and may not be suitable for urban environments. A raker is an enormous kickstand for your shoring wall.
These are easy to build, but they sit inside your excavation ( instead of outside, as with a tieback) and make life difficult when you need to build around them. They are a necessary evil when tiebacks are not possible or not allowed. How raking shore support is constructed varies from project to project and has to meet the specific conditions of each site.
How to use a scaffolding raker
May be used as an alternative to a tie and is generally considered to provide attachment for a 3m length on either side of the buttress or raker. A return is considered adequate for a 3m length measured from the outside corner.
Rakers should be set at an angle not more than two verticals to one horizontal and fixed at their base to prevent sinking or slipping. Tubes more than 2.7m in length should be fitted with a brace and tied back to the scaffold to prevent distorting under load.
The type of project you have underway will determine whether a scaffolding raker will be necessary. For them to provide stability, they should be braced and footed to avoid any incidents.