Lateral load application on cantilever wall 1

[GeoX]

A basic question with thanks in advance to those finding time to respond.

When applying the effect of strip loading behind a cantilever retaining wall:
is the distance between the wall and the strip load taken directly from the backface of the wall or is it taken from the 'virtual back' (i.e. line extending vertically from the heel to the surface)?

Thank you.

 

[GeoPaveTraffic]

I would take it from the actual back of the wall at the ground surface.

 

[GeoX]

Thanks for the response GeoPaveTraffic. That seems logical.

Yesterday I have noted that the Missouri Dep. of Transportation manual, Section 3.62, Page 1.2-4) see:

http://www.modot.state.mo.us/business/manuals/documents/Section3.62.pdf)

takes it from the virtual back - using Jarquio (1981).
For cantilever walls with long heel or L-shaped walls that can make quite a difference.... Hence I wanted to make sure I understand it right.

 

[cap4000]

GeoX

The active wedge line diagonally up from the footing determines whether or not surcharge pressures are actually felt by the wall itself. Thats different than the straight line to the load from the back face of the wall when the load is actually falls within the failure wedge area. Nice Link to a very informative website. Good Luck