DEFINITION

Maximum horizontal acceleration at ground surface (also known as peak ground acceleration)

Cyclic stress ratio

Relative density

Hammer efficiency

Lateral force reacting to earthquake-induced base shear

Factor of safety against liquefaction

Acceleration of gravity

Effective shear modulus at induced strain level

Shear modulus at a low strain level

Initial thickness of soil layer

Thickness of surface layer that does not liquefy

Thickness of soil layer that will liquefy during earthquake

Change in height of soil layer

Coefficient of earth pressure at rest

Value added to ( N ₁) ₆₀ to account for fines in soil

Uncorrected SPT blow count (blows per foot)

Japanese standard penetration test value for Fig. 7.1

FIGURE 7.1: Chart for estimating the ground surface settlement of clean sand as a function of the factor of safety against liquefaction FS _L . To use this figure, one of the following properties must be determined: relative density D _r of the in situ soil, maximum shear strain to be induced by the design earthquake ? _max, corrected cone penetration resistance q _{c 1} (kg/cm ²), or Japanese standard penetration test N ₁ value. For practical purposes, assume...