Please have a look at some of these PDFs ...

Dear Anoop Kumar Srivastava,

Thank you for your help.

The effect of swelling on shear strength is not clearly shown in those papers.

Dear Mr. Gobinath

the processes which result from the swelling process are a function of humidity (wet-dry) and slope angle (velocity). I attach a schematic diagram from which you can deduce the ensueing processes in terms of mass wasting and landscape incision.

Heave is the most important one in your case but no the only one.

I hope the sketches will give you an idea what might happen geomorphologically .

Regards

H.G.Dill

I do know that swelling of soils decreases the strength of the soil. This will happen only by decrease in the shear strength parameters, I.e. cohesion and friction angle. In bentonites which is fine grained and which cohesion predominates the strength, the cohesion will be affected.