Soil Arching

[Mike00]

Hello,

Can anyone give some references to effects of soil arching on underground openings.

I am trying to figure out when soil arching becomes a factor, at what depth does soil arching begin to aid in reducing the overburden pressure (of soil and a surcharge)above the tunnel. I am looking at shallow tunnels but would like to include in my analysis soil arching effects.

Thanks

 

[GeoPaveTraffic]

Arching occurs any time the stiffness of the installed structure is different than the stiffness of the surounding soil. If the structure is stiffer than the soil then load arches ON TO the structure. If the structure is less stiff than the soil then load arches AWAY FROM the structure.

The amount of arching depends on the relative difference in stiffness and the amount of load available to arch. Also keep in mind that the stiffness of soil is often differnet for long and short term loads, i.e. overburden and surcharge loads.

To directly answer your question, I'm not familiar with any references that quantify these effects and the only way I know to do so would be to complete a finite element study of the situation.

 

[PSlem]

I believe it was an Armco book that detailed this. Someone posted a list of out of print books they had downloaded to their site a couple weeks ago, maybe in the structural section.