compaction loading

[shorebob]

For designing soldier beam walls to retain backfill, I usually include an add-on pressure for compactive effort. Is this pressure residual, or, like traffic surchage, is it only present during actual backfill operations? I'm currently using a methodology from the Canadian Foundation Manual, 4th Ed. Any others out there?

 

[MSEMan]

Compaction effort can become locked in - see article by TS Ignold and BS 8006.

 

[dgillette]

See thread255-131863 for detailed discussion.

Try Duncan et al: "Estimation Earth Pressures due to Compaction" in the December 1991 ASCE JGE, with erratum in March 1992, and discussion and closure in July 1993. They have some chart solutions of possible benefit.

 

[Panars]

Minnesota Dept of Transportation sponsored some research that found the compaction-induced lateral pressures greatly reduced overnight.

http://www.research.dot.state.mn.us/detail.asp?productID=1975

 

[fattdad]

refer to Figure 14-8:

http://www.usace.army.mil/publications/armytm/tm5-818-1/ch-14.pdf

The affect of compaction locks in an increased horizontal earth pressure when the compaction takes place. Eventually there will be sufficient burial that the normal Ko or Ka earth pressure exceeds the compation effort. As such, the design earth pressure envelope is modified in the upper interval, extending to some depth.

Hope this helps.

f-d

¡papá gordo ain’t no madre flaca!