Bentonite Clay

Name of test
Atterberg Limit
Description of test
Have you ever carried out an Atterberg Limit on material that has a Plasticity Index of around 500? Let me introduce you to Bentonite.
Bentonite is a natural clay that is renowned for its exceptional ability to absorb and retain water, which allows the clay to swell and increase in volume by 8 times. When Bentonite comes into contact with water, its particles expand, forming a gel-like substance with impressive swelling capabilities. Because of this one of our clients was using Bentonite to line dams and caught our curiosity about the plasticity properties of this clay, thus, we decided to carry out a quality assurance activity for an Atterberg Limit in the Katherine lab.
During the test, it quickly became clear Bentonite is not a normal clay. After adding almost a litre of water to 100gr of Bentonite, we eventually reached the liquid limit of this material before curing the samples for 14 days due to the continuous absorption of water by the Bentonite clay.