Effect of void ratio on K of loose sand

The coefficient of lateral earth pressure at rest, K₀, is one of the key soil parameters for geotechnical design. For normally consolidated soils, Jaky's equation (Jaky, 1944),

where ϕ′ is the effective friction angle of soil, has often been used to estimate the K₀ value. According to equation (1), the K₀ value in general changes with the friction angle of soil, but will be constant for loose sand, as the friction angle for loose sand is the same as the friction angle at the...