PREFACE 



This report is published to provide coastal engineers with the re^^ 

 of research on the reflection and transmission characteristics of porous 

 rubble-mound breakwaters. The work was carried out under the coastal 

 processes program of the U.S. Army Coastal Engineering Research Center 

 (CERC) . 



Tlie report was prepared by Ole Secher Madsen, Associate Professor of 

 Civil Engineering, and Stanley M. IVliite, Graduate Research Assistant, 

 Ralpli M. Parsons Laboratory, Department of Engineering, Massachusetts 

 Institute of Technology, under CERC Contract No. DACW72-74-C-0001 . The 

 research was conducted at the Ralph M. Parsons Laboratory from 1 December 

 1973 through 30 November 1975. The authors acknowledge the assistance of 

 Mr. James W. Eckert, who participated in the development of the accurate 

 method for determining experimental reflection coefficients. The advice 

 and encouragement of Dr. Robert M. Sorensen, Chief, Special Projects 

 Branch, CERC, are greatly appreciated. 



Dr. R.M. Sorensen was the CERC contract monitor for the report, under 

 the general supervision of Mr. R.P. Savage, Chief, Research Division. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79 .i^ 

 Congress, approved 31 July 1945, as supplemented by Pu blic Law 172, 88 

 Congress, approved 7 November 1963. /^ ""~**>>^ 



JAMES L. TRAYER^ 



Colonel, Corps \/ Engineers 



Commander and Director 



