What is the maximum allowable slope for simple slope excavation that is 20 feet or less in depth?

The maximum allowable slope for simple slope excavation that is 20 feet or less in depth is indeed 53 degrees. This angle is determined based on established safety standards and engineering practices for excavation work that ensure the stability of the excavation site.

A slope angle of 53 degrees corresponds to a ratio of approximately 1:1. This means that for every one foot of vertical depth, the excavation should extend one foot horizontally. This configuration helps to reduce the risk of collapses, ensuring that the soil can adequately support itself without sliding.

Understanding the significance of excavation slopes is crucial for safety in construction and excavation projects. Proper slope angles prevent soil failure and protect workers in and around the excavation area. The other angles listed do not comply with safety guidelines for such depths, which further emphasizes the importance of adhering to the recommended slope for maintaining structural integrity during excavation activities.