PREFACE 



This report is published to assist coastal engineers and scientists 

 dealing with wave action at pile- supported structures by providing re- 

 sults from a laboratory study o£ wave transformation at a variety of 

 vertical piles. The tests were conducted at the U.S. Army Coastal 

 Engineering Research Center (CERC) during an effort to develop a near- 

 shore wave direction gage utilizing wave transformation at a surface- 

 piercing pile. The study was carried out under the wave dynamics program 

 of CERC. 



The report was prepared by Robert J. Hallermeier, Oceanographer, 

 Coastal Processes Branch, with assistance by Robert E. Ray, Civil 

 Engineer, Coastal Design Criteria Branch. Dr. Hallermeier worked under 

 the general supervision of Dr. C.J. Galvin', Jr., Chief, Coastal Processes 

 Branch, who initiated the study. The tests were performed by J.C. Jones, 

 R.J. Karlitskie, R.E. Ray, and C.R. Schweppe, with continuing assistance 

 by R.P. Stafford. J.C. Ahlquist, D.C. Fresch, B.H. Gwinnup, L.B. Keely, 

 C.F. Thomas, and S.B. Ward assisted with the data reduction and display, 

 and J.T. Dayton assisted with the photography. 



Comments on this publication are invited. 



Approved for publication in accordance with Public Law 166, 79th 

 Congress, approved 31 July 1945, as supplemented by Public Law 172, 

 88th Congress, approved 7 November 1963. 



2^ 



^JOHN H. COUSINS 

 Colonel, Corps of Engineers 

 Commander and Director 



