passive pressure for shear key
passive pressure for shear key
(OP)
A foundation has been designed for a very high containment barrier on the depature of a bridge. Because the size of foundation is too small to resist sliding, a shear key has been provided. The question is, since the foundation is on the edge of the embankment and the only soil retained by the key is 3m of soil beneath the rest of the foundation and then the embankment falls off at 45 degrees, can you really consider the passive pressure provided by the key? If no at what distance can the passive pressure be mobilised. If it was ground level then you could consider it infinitely long. help out





RE: passive pressure for shear key
Also, multiple shear planes should be checked. It is much like doing a slope stability analysis. In fact, I have often used slope stability software to do additional checks.
RE: passive pressure for shear key
RE: passive pressure for shear key
RE: passive pressure for shear key
RE: passive pressure for shear key
I don't understand this comment. If you generate a free body diagram of the soil between the shear key, the base of the wall, and the slope, the shear on the bottom of the surface is a limiting factor as to what can be generated by the shear key. If I'm missing something, let me know.
RE: passive pressure for shear key
ht
RE: passive pressure for shear key
If i understood what you said. I thought you were referring to the shear plane that should be checked as indicated in EC hambly Bridge foundations and substructures. If that is the one, i have checked that since the free body diagram for that also includes the weight of the foundation acting at an angle and also the soil capacity not to shear against the impact force at angle. If i got you right then that has been checked and the free body diagram indicates foundation will not pull out in that fashion. Thanks for all the comments and those received from the others. i have used the log spiral chart for the decreased passive pressure