What must be considered before allowing excavation to proceed near support systems?

In excavation work, particularly near support systems such as foundations, retaining walls, or utilities, it is crucial to consider the forces that these support systems are designed to resist. This is essential because support systems are engineered to bear certain loads and resist various stresses. When excavating nearby, the removal of soil can change the load distribution and impact the stability of those systems.

Understanding the maximum loads and the type of forces (tensile, compressive, lateral) these supports can handle ensures that the excavation does not inadvertently compromise their integrity. For example, if an excavation reduces the soil pressure against a foundation wall, it might lead to increased lateral forces acting on it, potentially causing failure.

In addition, evaluating the forces at play can guide the need for additional measures, such as bracing or shoring, to provide temporary support during the excavation process. This proactive approach is vital for maintaining safety and preventing accidents on site.

In contrast, factors such as the availability of workers, the color of the soil, and the time of day, while relevant to various aspects of excavation operations, do not directly influence the structural integrity or load-bearing capacity of support systems and therefore are not primary considerations in this context.