Lateral Earth Pressures from a rock cut slope on a retaining wall 1

[adidasmayo]

Hi Everyone,

I have a unique situation where I am building a house by cutting into a hillside for my building pad. The backside will be a near vertical cut in rock and there are two retaining walls that will be almost stacked on top of each other. See image.
How do I determine the lateral earth pressures including seismic in this scenario?

Thanks

 

[bridgebuster]

There's a paper in the 1987 ASCE Journal of Geotechnical Engineering "Earth Pressure on Retaining Walls Near Rock Faces" by Frydman, which explains how to calculate Ka. I can't post the paper because it's copright material. Try this link, that was posted here a few years ago:

Link

 

[adidasmayo]

Thank you so much for your very prompt response bridgebuster. I have already purchased that paper and have reviewed it. What about for seismic conditions on restrained walls?

Any idea there?

 

[HENRYZAU]

If a vertical cut can be done, there must be no adverse defects/beddings etc, Earth pressure should be zero. Earth pressure theory ka or kp does not apply for rocks, except very weak rock like soils.

 

[adidasmayo]

Hi Henryzau,

Thank you very much for your response. What about the little amount of granular backfill required behind the wall for drainage purposes?