What type of support systems may be required when excavation endangers the stability of adjoining structures?

When excavation work is being carried out in proximity to existing structures, it is crucial to implement support systems to prevent soil movement and ensure the stability of the adjoining buildings. Bracing and shoring are both essential techniques used in such scenarios.

Bracing refers to the use of supports that provide lateral stability to the excavation walls, reducing the risk of collapse. This can involve installing diagonal braces that shore up adjacent structures or excavated areas, thus stabilizing the soil and maintaining the integrity of both the work site and surrounding properties.

Shoring, on the other hand, involves providing temporary support to structures to prevent them from falling or shifting during excavation. This can include hydraulic shoring systems, which use hydraulic equipment to apply pressure and hold up the soil, or other types of shoring that directly support the existing structures.

Since both bracing and shoring help to mitigate risks associated with excavation, the combination of these techniques is often required to ensure the safety and stability of not only the excavation site but also the adjacent structures. Therefore, the correct choice includes both bracing and shoring as necessary support systems for safe excavation practices.