What is the acceptable relative bearing strength of sedimentary rock, measured in psf?

The acceptable relative bearing strength of sedimentary rock, generally recognized within engineering and construction contexts, is approximately 20,000 pounds per square foot (psf). This value is determined based on the rock's inherent properties, including its density and composition, which directly influence its load-bearing capabilities.

Sedimentary rocks, being consolidated from various materials over time, exhibit varying strengths depending on the degree of compaction and mineral composition. The standard figure of 20,000 psf serves as a guideline for engineers when assessing the soil capacity for structural foundations, providing a conservative estimate that ensures stability and safety in construction.

Values lower than this benchmark, such as 10,000 or 15,000 psf, could lead to compromised structural integrity if applied to projects requiring higher load capacities. On the other hand, values exceeding 20,000 psf, like 25,000 psf, while potentially applicable in certain contexts, might not represent typical conditions for sedimentary rock and thus might suggest more stringent testing or localized conditions rather than standard practice.