coefficient of earth pressure at rest
Technical term in geotechnical engineering; refers to the ratio of horizontal to vertical effective stress when a soil mass is not undergoing lateral deformation.
In retaining wall design, it is necessary to estimate the coefficient of earth pressure at rest appropriately.
Compound of 静止 (seishi, 'at rest') + 土圧 (doatsu, 'earth pressure') + 係数 (keisū, 'coefficient'). A direct technical translation from English 'coefficient of earth pressure at rest'.