Abstract
The use of sand drains to accelerate the consolidation of soft, fine-grain soils has been widely used in California Difficulty has been encountered in predicting the action of sand drains during the design of these projects. Accordingly, the experimental fill at Napa River was constructed to obtain information to better understand the action of sand drains. It was found that sand drains did not accelerate the consolidation of the soft foundation soil as rapidly as theory would indicate. It appears that the method of placing the sand drains with a closed mandrel was one of the main causes of reduction in the expected rate of consolidation.