Preface 



This study was conducted by the Coastal Engineering Research Center (CERC), US Army Engineer 

 Waterways Experiment Station (WES). The work described herein was authorized as a part of the Civil 

 Works Research and Development Program by the Headquarters, US Army Corps of Engineers 

 (HQUSACE), and was performed under the Scour at Coastal Structures Work Unit 31715, which is in the 

 Coastal Shore Protection and Restoration Program, CERC. Messrs. John H. Lockhart, Jr.; James E. 

 Crews; and John G. Housley are HQUSACE Technical Monitors. Dr. Charles L. Vincent is Program 

 Manager for the Coastal Shore Protection and Restoration Program at CERC. 



This study was performed and the report prepared over the period 1 August 1988 through 30 Dec- 

 ember 1989 by Dr. Steven A. Hughes, Research Hydraulic Engineer, Wave Dynamics Division (WDD), 

 CERC, and Dr. Jimmy E. Fowler, Research Hydraulic Engineer, Wave Processes Branch, WDD, CERC. 

 Dr. Fowler was Principal Investigator of the Scour at Coastal Structures work unit during this period. 



The research effort was under general administrative supervision of Dr. James R. Houston, Chief, 

 CERC, and Mr. Charles C. Calhoun, Jr., Assistant Chief, CERC. Mr. Gene Chatham, Chief, WDD, and 

 Mr. Douglas Outlaw, Chief, Wave Processes Branch, provided direct supervision of Dr. Hughes and 

 Dr. Fowler, respectively. 



The authors gratefully acknowledge the dedicated efforts of the following personnel who helped during 

 the laboratory phases of the study. Mr. John E. Evans, CERC, was the laboratory technician overseeing 

 the physical model; wave data reduction was performed by Mses. Robin Hoban and Christie Sanders, 

 CERC; installation and maintenance of instrumentation and day-to-day operation of the wave machine and 

 data acquisition systems were performed by Messrs. David Daily, Ricky Floyd, and Lonnie Friar, 

 Instrument Services Division, WES. The report was edited by Ms. Lee Byrne, Information Technology 

 Laboratory, WES. 



Special acknowledgment is given to Dr. Hans H. Dette, Technical University of Braunschweig, and 

 Dr. Klemens Uliczka, University of Hannover in the Federal Republic of Germany, for making available their 

 prototype-scale physical model results which formed the basis of comparison for the tests reported herein. 

 Their cooperation throughout the course of the study contributed largely to the success of the research. 



COL Larry B. Fulton, EN, was Commander and Director of WES during preparation of the report. 

 Dr. Robert W. Whalin was Technical Director. 



