Reevaluation of Soil Compression Properties for an Aluminum Refinery Plant

The foundations supporting the high and heavy storage tanks at an alumina refinery plant experienced extremely large settlements and the normal operations of the tanks have been affected. To find the reasons for the unexpected large settlements of the foundations, the original design was reviewed and the soil compression properties used for calculating the foundation settlement was checked. It was found that the compression index values used in the original design were too small and the effect of sample disturbance on the compression index was not considered when using the laboratory consolidation test results. By using the Schmertmann correction procedure to consider the effect of soil disturbance, new compression index values were determined. The corrected compression index values were used to calculate the settlements of the foundations and the predictions were in good agreement with the field settlement measurements. This study further indicates the importance of considering the effect of sample disturbance in the determination of soil compression index values using laboratory consolidation tests.