Check for sliding (pad and strip base:ACI 318)

Tekla Structural Designer
2021
Tekla Structural Designer

Check for sliding (pad and strip base:ACI 318)

The check for sliding is carried out for pad foundations only.

If there is no horizontal force acting on foundation check for sliding is not required.

Resultant Force on foundation:

Hd = √[(Fx,sup)2 + (Fy,sup)2]

Resultant Force Angle αHd = tan-1 [(Fy,sup / Fx,sup)]

where

Fx,sup = horizontal force acting on support in X-dir. (from analysis)

Fy,sup = horizontal force acting on support in Y-dir. (from analysis)

Resistance to sliding due to base friction:

Hfriction = [-P + Fswt] * tanδ

where

δ = design base friction – user input

Passive pressure coefficient:

Kp = (1+sinΦ’) / (1-sinΦ’)

where

Φ’ = design shear strength of soil – user input

Passive resistance of soil in X direction:

Hxpas = 0.5*Kp*(h2 +2*h*hsoil)*Lx* ρsoil

Passive resistance of soil in Y direction:

Hypas = 0.5*Kp*(h2 +2*h*hsoil)*Ly* ρsoil

Resultant Passive Resistance:

Hres,pas = abs(Hxpas*cos αHd) + abs(Hypas*sin αHd)

Total resistance to sliding:

RHd = (Hfriction + Hres,pas) / 1.5

If

RHdHd

The check for stability against sliding passes

Was this helpful?
Previous
Next