Test Results 



1 . Neither the shape of the plates (whether round or square) nor the plate 

 settlement rate, within the range imposed, appeared to have a significant 

 effect on the bearing pressure— settlement relationship. 



2. The plate size appeared to have no effect on the bearing pressure— settlement 

 relationship at the Series 1 1 1 site and to have an inconsistent effect on the rela- 

 tionship at the Series IV site. This behavior, which conflicts with some generally 

 accepted soil mechanics concepts, is thought to be partially attributable to the 

 soil shear strength profiles existent at the two sites. 



3. At the Series 1 1 1 site soil strength increased approximately linearly with 

 depth from a value near zero at the surface. At the Series IV site strength 

 also increased linearly with depth but from a distinctly non-zero surface value. 



Data Analysis 



T The data obtained in the two test series reported here and in a cohesive 

 soil test series reported earlier may be analyzed in terms of elastic theory and 

 bearing capacity theory. 



2. The elastic theory solution was utilized successfully in analyzing all of the 

 plate bearing data considered. However, the use of empirical relations between 

 elastic parameters and shear strength data based on the plate bearing test results 

 was found to be necessary. 



3. Bearing capacity theory was successfully applied to the test data for 

 relatively high bearing pressures. No additional empirical correlations were 

 needed for this application. 



4. A suggested technique for predicting immediate settlements was developed 

 and presented. 



CONCLUSIONS 



1. The equipment described in this report provides a means of obtaining 

 information on the short-term response of marine sediments to surface- 

 loaded footings. 



2. The data obtained may be analyzed using modified versions of current 

 theory for terrestrial soils. The most significant factor affecting the applica- 

 tion of these theories is the distribution of soil shear strength with depth. 



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