Definition and Use of the Phi Grade Scale.

Abstract

The Unified Soils, Wentworth, and phi grade scales are commonly used by coastal engineers to describe sediment texture. Of these, the phi scale is least understood. This report discusses why the phi scale was proposed initially, and how and when it should be used. Formulas and methods are presented for using the phi notation, calculating the mean grain size, and sorting of sediment samples, and for converting between phi-and millimeter-based size scales. Sample calculations show how the phi grade scale can be used to classify and analyze sediment texture.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1979
Accession Number
ADA080983

Entities

People

  • Richard D. Hobson

Organizations

  • Coastal Engineering Research Center

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Beaches
  • Classification
  • Coastal Engineering
  • Conversion
  • Data Science
  • Diameters
  • Engineering
  • Engineering Geology
  • Engineers
  • Equations
  • Grain Size
  • Particle Size
  • Particles
  • Skewness
  • Soil Classification
  • Soils
  • Standards

Readers

  • Computer Vision.
  • Graph Algorithms and Convex Optimization.
  • Hydraulic Engineering.