SOIL SHRINKAGE FACTOR

Professional Engineer & PE Exam Forum

Help Support Professional Engineer & PE Exam Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

barracus79

Member
Joined
Apr 1, 2010
Messages
13
Reaction score
0
Is it:

bank dry density / compacted dry density

or

compacted dry density / bank dry density

I have a couple of sources that say bdd/cdd and I have one that says cdd/bdd*.

Just in common sense terms, shrinkage factors are typically 0.8-1.0, and for soil, compacted dry density is going to be higher bank dry density, so using typical shrinkage factors of <1, the compacted dry density should be in the denominator and bdd/cdd should be correct.

*the one source is the new construction afternoon depth reference that came out this summer.

 
Is it:
bank dry density / compacted dry density

or

compacted dry density / bank dry density

I have a couple of sources that say bdd/cdd and I have one that says cdd/bdd*.

Just in common sense terms, shrinkage factors are typically 0.8-1.0, and for soil, compacted dry density is going to be higher bank dry density, so using typical shrinkage factors of <1, the compacted dry density should be in the denominator and bdd/cdd should be correct.

*the one source is the new construction afternoon depth reference that came out this summer.

Kaplan " Civil engineering Pe Licence Review" 17 th ed page 493

Swell factor = Loose unit wt/ Bank unit wt

Shrink factor = bank unit weght/Bank unit weght

in my notes (from CERM p 79-1 11th ed) Shrink. factor = dry density (field) / dry density (compacted) -1

 
Back
Top