In absence of tests, what is the assumed load bearing capacity of clay soil?

The assumed load-bearing capacity of clay soil, when specific tests are not available, is typically estimated to be around 1,500 pounds per square foot. This figure is based on general engineering practices and soil mechanics, where clay soil is known to have moderate to high strength under proper moisture conditions.

This load-bearing capacity can vary depending on factors such as moisture content, compaction, and the presence of other materials mixed with the clay. However, unless detailed testing is conducted, engineers and contractors tend to rely on this established value for clay soil as a baseline to ensure safety and structural integrity during construction projects.

The other options represent estimates that exceed what is commonly accepted for clay soil. These figures are more aligned with firmer soils, such as gravel or sandy soils, which possess higher shear strength and can support greater loads. Therefore, 1,500 pounds per square foot is the more realistic and conservative estimate for clay soil when specific testing data is not available.