"Symbols and definitions used in geotechnical engineering" is quoted from "Lexicon in 8 languages" (the fifth edition) published in 1981 by International Society for Soil Mechanics and Geotechnical Engineering.
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5. Practical Problems
a) Earth Pressure
| Symbol | Dimension | Unit | Measured quantity | Description |
| \(\delta\) | - | ° | Angle of wall friction | Angle of friction between all and adjacent soil |
| \(a, c_a\) | ML-1T-2 | kPa | Wall adhesion, pile shaft adhesion | Adhesion between wall, or pile shaft and adjacent soil |
| \(K_a, K_p\) | - | 1 | Active and passive earth pressure coeffcients | Dimensionless coefficients used in expressions for active and passive earth pressure |
| \(K_o\) | - | 1 | Coefficient of earth pressure at rest | Ratio of lateral to vertical effective principal stress in the case of no lateral strain and a horizontal ground surface |
b) Foundations
| Symbol | Dimension | Unit | Measured quantity | Description |
| \(B\) | L | m | Breadth of foundation | |
| \(L\) | L | m | Length of foundation | |
| \(D\) | L | m | Depth of foundation beneath ground | |
| \(Q\) | MLT-2 | kN | Applied (axial) load | |
| \(q\) | ML-1T-2 | kPa | Applied (axial) pressure | |
| \(q_1\) | ML-1T-2 | kPa | Limit pressure | |
| \(Q_p\) | MLT-2 | kN | Point resistance force | |
| \(q_p\) | ML-1T-2 | kPa | Point resistance pressure | |
| \(Q_s\) | MLT-2 | kN | Total shaft resistance | |
| \(q_s\) | ML-1T-2 | kPa | Unit shaft resistance | |
| \(H\) | MLT-2 | kN | Lateral force applied to a foundation | |
| \(s\) | L | m | Settlement | |
| \(e\) | L | m | Eccentricity | Distance of point of application of force to center line of the base of the foundation |
| \(\delta\) | - | ° | Inclination of load | Angle of load force with perpendicular to base of foundation |
| \(k_s\) | ML-2T-2 | kN/m³ | Modulus of subgrade reaction | Ratio between change of vertical stress on a rigid plate and corresponding change of vertical settlement of the plate |
| \(N_c\), \(N_q\), \(N_\gamma\) | - | 1 | Bearing capacity factors | Dimensionless coefficients used in expressions for bearing capacity as a function of \(\sigma\) and \(\phi\) |
| \(i_c\), \(i_q\), \(i_\gamma\) | - | 1 | Correction factors for inclination | Correction factors for the bearing capacity factors in the case of an inclined load |
c) Slopes
| Symbol | Dimension | Unit | Measured quantity | Description |
| \(H\) | L | m | Vertical height of slope | |
| \(D\) | L | m | Depth below toe of slope to hard stratum | |
| \(\beta\) | - | ° | Angle of slope to horizontal | |
| \(\bar\tau\) | ML-1T-2 | kPa | Average shear strength mobilized along sliding surface | |
| \(R\) | - | 1 | Residual factor | Defined as: \(\large R=\frac{\tau_f-\bar\tau}{\tau_f-\tau_R}\) |
| \(r_u\) | - | 1 | Pore pressure ratio | Ratio between the in-situ pore pressure and the total overburden pressure: \(\large \frac{u}{\gamma_z}\) |