Encyclopedia of Engineering Geology

2018 Edition
| Editors: Peter T. Bobrowsky, Brian Marker

Pore Pressure

  • Michael T. HendryEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-73568-9_226


Pore pressure (u) within a soil is the net pressure of the fluids within the voids that exist between the soil particles. Pore pressure is most commonly associated with pore water, which has a pore-water pressure (uw). Pressures of other fluids such as pore-air pressure (ua) and other non-soluble materials may be considered for specialized analyses.

The simplest spatial distribution of u w is the result of hydrostatic pressure, where the pressure at a given point is the result depth below the phreatic surface, and thus u w increases with increasing depth. Where the phreatic surface or water table is the height of water within observation wells that correspond to a u w equal to zero. The hydrostatic pressure can be calculated from the unit weight of water ( γ w), and the depth ( d) below the phreatic surface (Terzaghi et al. 1996).
$$ {u}_w={\gamma}_wd $$
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  1. Terzaghi K, Peck RB, Mesri G (1996) Soil mechanics in engineering practice, 3rd edn. Wiley, New YorkGoogle Scholar

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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department Civil and Environmental EngineeringUniversity of AlbertaEdmontonCanada