Question

In Terzaghi’s formula K = 200De2e2, De2 represents ____________

(a) Effective grain shape

(b) Void ratio

(c) Effective grain size

(d) Permeability

This question was posed to me during a job interview.

My doubt is from Determination of Coefficient of Permeability in portion Permeability of Geotechnical Engineering I

Answer 1

Correct option is (c) Effective grain size

To explain I would say: De=effective grain size, the diameter of the sphere for which the ratio of its volume to its surface area is the same as the similar ratio for a given assemblage of soil particles.