Geotechnical Glossary: Bulk Density

"Mistakes beget mistakes."

Peter Smart

Preliminary Draft: 2007.03.09:
Some sources not yet in hand.

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Basic Definitions

The correct definitions
Scope = soil mechanics
Symbol [M, L, T] Name Definition
[1,-3, 0]
bulk density total mass divided by total volume.
[1,-3, 0]
dry density mass of solids divided by total volume.
bulk unit weight total weight divided by total volume.
dry unit weight weight of solids divided by total volume.

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The basic terms are:

Hence, ‘bulk density’ is the collective mass in a unit of volume, which is the same as ‘total mass divided by total volume’.

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Principal sources

In considering the older sources, remember that ‘weight’ was a measure of quantity in those days.

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Additional sources

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Incorrect definitions

Instead of using ‘dry density’, the sources listed below defined ‘mass of solids divided by total volume’ as ‘bulk density’.

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Still under consideration.

“ratio of the mass of a quantity of material (or one phase) and the total volume occupied by this material (including other phases)” (26: ISO 11074: Section 3.1.1: 2005). On this basis, we seem to need: ‘bulk density of soil in its natural state’ for ‘bulk density’; and ‘bulk density of soil particles’ for ‘dry density’: also, we seem to be able to have ‘bulk density of selenium’ for ‘mass of selenium per unit volume’.

SSEW (23: 1974, p.91) used the term ‘moist bulk density’.

Etude Geotechnique (27: 1983, p.124) used the terms ‘le poids volumique du sol humide’ and ‘le poids volumique du sol sec’; but ISSMFE used ‘masse volumique’ and ‘masse volumique du sol sec’ (2: ISSMFE, 1981, pp.13 & 35).

density of the soil: “ratio of the weight of soil to the corresponding volume” (28: Bowles, 1977, p.11).

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1. OED. The Oxford English Dictionary. Electronic ed. Oxford: Oxford University Press, 2002.

2. ISSMFE. Lexicon in 8 Languages: Technical Terms, Symbols and Definition in English, French, German, Italian, Portuguese, Russian, Spanish and Swedish Used in Soil Mechanics and Foundation Engineering. Fifth ed. International Society for Soil Mechanics and Foundation Engineering, 1981. (Printed by The Bryant Press Limited, Toronto, Ontario, Canada.)

3. BS 1377. Methods of Test for Soils for Civil Engineering Purposes, 1990. [Nine parts.]

4. DSIR. Soil Mechanics for Road Engineers. Edited by D.J. Maclean. London: HMSO, 1952.

5. Capper, P.L., and W.F. Cassie. The Mechanics of Engineering Soils. London: Spon, 1949.

6. Geotechnique. “Soil Mechanics Nomenclature.” Geotechnique 2 (1950): 84-86.

7. Terzaghi, K. Theoretical Soil Mechanics. New York: Wiley, 1943.

8. Akroyd, T.N.W. Laboratory Testing in Soil Engineering. London: Soil Mechanics Ltd., 1957.

9. Yong, R.N., and B.P. Warkentin. Introduction to Soil Behaviour, 1966.

10. Scott, C.R. An Introduction to Soil Mechanics and Foundations. London: MacLaren and Sons, 1969.

11. Head, K.H. Manual of Soil Laboratory Testing. Vol.1. Soil Classification and Compaction Tests. Plymouth: Pentech Press, 1980.

12. Lee, I.K., W. White, and O.G. Ingles. Geotechnical Engineering. Boston Mass.: Pitman, 1983.

13. Head, K.H. Manual of Soil Laboratory Testing. Vol.1. Soil Classification and Compaction Tests. Second ed. London: Pentech Press, 1992. [ Unchecked ]

14. Scott, J.S. The Penguin Dictionary of Civil Engineering. Fourth ed. London: Penguin, 1991. [First Edition 1958.]

15. Chudley, R. Building Construction Handbook. Second ed. Oxford: Newnes, 1995.

16. Cox, D.W. “A New Field Test for the ‘Degree of Compaction’.” In Advances in Site Investigation Practice, edited by C. Craig, 487-98. London: Thomas Telford, 1996.

17. Craig, R.F. Soil Mechanics. Sixth ed. London: Spon, 1997.

18. ------. Soil Mechanics. Seventh ed. London: Spon, 2004.

19. Head, K.H. Manual of Soil Laboratory Testing. Vol.1. Soil Classification and Compaction Tests. Third ed. London ?: Whittles Publishing, 2006. [ Ground Engineering Sept 2006 p.8 ]

20. SSSA. Glossary of Soil Science Terms. Madison, Wisconsin: Soil Science Society of America, 1997. [First Edition 1956.]

21. Buckman, H.O., and N.C. Brady. The Nature and Properties of Soils. Sixth ed. New York: Macmillan, 1960.

22. Brewer, R. Fabric and Mineral Analysis of Soils. New York: Wiley, 1964.

23. SSEW. Soil Survey Field Handbook. Edited by J.M. Hodgson. Soil Survey Technical Monograph No.5. Harpenden: Soil Survey of England and Wales, 1974.

24. Yong, R.N., and B.P. Warkentin. Soil Properties and Behaviour, 1975.

25. Stein, J.S. Construction Glossary: An Encyclopedic Reference and Manual. New York, NY: Wiley, 1980.

26. BS ISO 11074. Soil Quality: Vocabulary, 2005.

27. “Etude Geotechnique et Reconnaissance Des Sols.” Revue Française de Geotechnique. Paris: Presses de l’Ecole Nationale des Ponts et Chaussées, YEAR.

28. Bowles, J.E. Foundation Analysis and Design. New York: McGraw-Hill, 1977.

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(C) Peter Smart.