Undrained Shear Strength of Compacted Clay
Undrained Shear Strength of Compacted Clay
(OP)
The clay fill will be placed in 8-inch-thick lifts and compacted to 95% of the maximum dry density per Standard Proctor method. The borrowed clay material (non-organic) has medium plasticity (LL between 30 and 50). What would be the undrained shear strength (range) from this compaction? Is there any literature related to this aspect? Thanks.





RE: Undrained Shear Strength of Compacted Clay
"An Introduction to Geotechnical Engineering" and "Soil Mechanics in Engineering Practice-3rd Edition" have such information.
RE: Undrained Shear Strength of Compacted Clay
Not much need for it now working for the City.
RE: Undrained Shear Strength of Compacted Clay
Please help me have a look at your reference and let me know. I have a sheet pile wall to install which needs removal of extremely soft subgrade and replace it with compacted clay. I agree with fndn that I will also need to do a UU triaxial test on the compacted clay to confirm the assumed Su. Thanks for your advice.
RE: Undrained Shear Strength of Compacted Clay
One caution on compacted clay fills - need to keep your lifts proper. I know one job that had major problems in tha the upper part of the lift was compacted and the lower part not nearly enough. After construction distress, they found this clearly evident by moisture content profile and undrained shear strength profile.
I would also surmise that the methods of compaction are very important as well. Use of sheepsfoot roller or PTR rather than vibratory. In the lab, things always are "ideal" in that the sample before compaction would be of similar gross gradation (i.e., clump gradation) but on the job site, clay borrow usually comes in much bigger clumps. If there is no care in breaking down the clumps before compaction, you might only pack the clumps together in a non-homogeneous mixture. The interconnected voids would have effects on the permeability of the fill mass as well on the strength of the mass.
Just some initial thoughts.