Critical Slip Surface Location

I have created a model for an embankment slope. The critical slip surface is located only within in the embankment fill and is creating a narrow sliver of failure.

How do I ensure the model is running through the native soft clays at the base of the embankment.

I am sorry I just back from vacation, supposed to designate the other engineer who can take care of this ticket.

My falut, I apologize again,

Limit equilibrium method is based on the assumed failure surface. The most critical means just the smallest F.O.S.

If you want to check F.O.S, along the designated failure surface, you have to use the other options such as polygonal failure surface.

Based on the material parameter you input, the factor of safety through the native soft clays is about more than 3. 

This is the correct result. 

If you want to make it the smallest one, you can simply change the assumed failure surface like the modified model I enclosed here.

Please keep in mind, for LEM, it is up to you, the assumed failure surface.

Thanks and Regards,

Bae

Americas Regional Manager