At rest (ko) wedge?
At rest (ko) wedge?
(OP)
We can calculate the active (ka) wedge distance and passive (kp)mwedge distance behind/in front of a wall.
is there such thing as an "at-rest" (ko) wedge and if so, how do i calculate it?
is there such thing as an "at-rest" (ko) wedge and if so, how do i calculate it?





RE: At rest (ko) wedge?
RE: At rest (ko) wedge?
f-d
ípapß gordo ainÆt no madre flaca!
RE: At rest (ko) wedge?
So what about at-rest pressures - Fat Dad thinks 45 degrees..can you explain Fat Dad?
RE: At rest (ko) wedge?
RE: At rest (ko) wedge?
f-d
ípapß gordo ainÆt no madre flaca!
RE: At rest (ko) wedge?
If however, you have a case where the wall rotates but the deflection is less than 0.001H (say 1 mm), then you can assume the failure wedge for active condition is an upper bound solution. This gives you a setback of about 0.5H to 0.8H to the failure plane from the back face of the wall.
http://www.soilstructure.com/
RE: At rest (ko) wedge?
f-d
ípapß gordo ainÆt no madre flaca!
RE: At rest (ko) wedge?
RE: At rest (ko) wedge?
I have a stepped 2 level basement ret wall that will be propped by the slabs at ground level, -1 level and -2 level.
the upper basement wall is 3m high
the lower basement wall is 3m high
the distance between the upper and lower walls is 5m
the walls will be restrained at the top of the walls by the basement slab so we are assuming ko (at-rest) conditions
unit weight of soil=20kN/m3
ko say 0.5
the question is..
will the upper wall load up the lower wall? or can i assume they are completely independent? i.e. upper wall with a triangular pressure distribution of 0 kPa at the top and 0.5 x 20 x 3 = 30kPa at the bottom and the lower wall with exactly the same pressure distribution (0kPa at the top and 30kPa at the bottom).
RE: At rest (ko) wedge?
The pressure may not be triangular, but rather trapezoidal. And if the offset of the upper wall is to the earth side, the upper levels may also impose a surcharge on the lower level wall.
Suggest you have your geotechnical consultant take a close look at this section through the building and advise accordingly.
RE: At rest (ko) wedge?
f-d
ípapß gordo ainÆt no madre flaca!
RE: At rest (ko) wedge?
Not sure this is a solution but I would look at it a couple of ways before I would treat them as being independent.
RE: At rest (ko) wedge?
The OP has a 2 level basement wall, braced by the building at 3 levels, not 2 cantilevered walls. Sliding or overturning should not be issues.
RE: At rest (ko) wedge?
"I have a stepped 2 level basement ret wall that will be propped by the slabs at ground level, -1 level and -2 level.
the upper basement wall is 3m high
the lower basement wall is 3m high
the distance between the upper and lower walls is 5m
the walls will be restrained at the top of the walls by the basement slab so we are assuming ko (at-rest) conditions"
I am not sure how a basement wall is restrained at the top by the basement slab. I think I need a sketch.
RE: At rest (ko) wedge?