Summary 



Sediment density and pore pressure were measured to complement the 

 other SUPERTANK studies. Twenty-nine samples were acquired on seven 

 different days to evaluate variations in sediment density. Pore pressure mea- 

 surements were acquired at six to ten locations throughout the SUPERTANK 

 project. 



Sediment density varied considerably with location. Highly disturbed sites, 

 such as those on top of the berm, experienced much higher porosities (0.46) 

 as compared to regions onshore and offshore from the berm (0.29). These 

 variations have significant implications in evaluation of mass flux from 

 volume flux in sediment erosion computations. 



Pore pressures are shown to decrease both with depth and frequency. 

 Static pressures correlate well with observed mean water levels. The 

 complete data set will provide a useful database for validating hydrodynamic 

 models of wave-seabed interaction. 



Acknowledgements 



Oregon State University is grateful to the Coastal Engineering Research 

 Center of the U.S. Army Engineer Waterways Experiment Station for spon- 

 soring the SUPERTANK project, under Contract No. DACW 39-91-K-0013. 

 The authors thank the following OSU individuals for their spirit and helpful 

 contributions to the project: Cheryl Zedwick, Jeffrey Jones, Shawn Ellis, 

 James Washburn, and Joe Richards. The cooperation and creative input of all 

 SUPERTANK investigators and assistants were essential to the ultimate suc- 

 cess of this project. That effort is gratefully acknowledged. Finally, the 

 major responsibilities for this project have been borne by Nicholas Kraus and 

 Jane McKee Smith. The authors extend their appreciation to Nick and Jane 

 for their dedication. 



References 



Biot, M. A. (1941). "General theory of three-dimensional consolidation," J. 

 Appl. Phys. 12, 155-65. 



Madsen, O. S. (1978). "Wave-induced pore pressures and effective stresses in 

 a porous bed," Geotechnique 28, 377-93. 



McDougal, W. G., and Sollitt, C. K. (1984). "Geotextile stabilization of sea- 

 beds: Theory," Engnrg. Structures 6, 211-16. 



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