Which type of soil can be excavated with vertical side slopes while remaining intact?

The ability to excavate soil with vertical side slopes while keeping it intact primarily depends on its structural properties and cohesion. Stable rock is characterized by its density, strength, and ability to maintain its form, even when cut vertically. This structure allows for vertical excavation without the risk of collapse, making it a suitable choice for such operations.

In contrast, other soil types, such as sandy loam, clay soil, and granite, do not share the same characteristics. Sandy loam, while somewhat cohesive, may still require sloping for stability due to its granularity and potential for collapse under vertical cuts. Clay soil has significant cohesiveness but can be unstable if wet, leading to potential slumping. Although granite is also hard and durable, rigid strata like granite usually need proper blasting techniques for excavation rather than vertical cuts.

Understanding the behavior of these soils during excavation is crucial for safe and effective grading and excavation practices.