AN INVESTIGATION OF THIXOTROPY IN HIGHLY PLASTIC CLAYS.

This study was made to establish the effect of thixotropy on a specified clay and to determine if a means could be established where thixotropy can be predicted and then used in design. A review was made of the theories of thixotropy and how the strength increases takes place. Investigations performed by other authors were reviewed and their conclusions on the feasibility of using thixotropic strength increase in design was discussed. Two clays were used in the study. Each was prepared at three different water contents near the liquid limit. The samples were placed in two types of containers and stored under water. Shear strength is affected by changes in water content therefore a secondary study was to detemine the effectiveness of the methods used to control the water content of the stored samples. Samples were stored a maximum of 150 days. Tests were made at specified times during this period to determine the strength increase that developed with time. It was found that the strength increase of the clays tested could be defined by an equation. The accuracy of the equation was not determined for all water contents but only those used in the study. Author