CONSTRUCTION MATERIALS FOR COASTAL STRUCTURES 



by 



Moffatt and Niaholj Engineers 

 I. INTRODUCTION 



1 . G eneral . 



Construction materials for coastal structures may be classified into five 

 general categories: stone and earth, concrete, metals, wood, and synthetics. 

 Some of these categories are treated in more than one section in this report 

 in order to better clarify their use and performance in different structures. 

 For example, stone and earth are each discussed in separate sections, as are 

 Portland cement and other types of concrete and grout. The material require- 

 ments are discussed in sufficient detail to permit the coastal engineer and 

 structural designer to evaluate materials based on the physical properties of 

 these materials and the past performance in coastal structures use. Coastal 

 structures generally considered are breakwaters, groins, seawalls, bulkheads, 

 revetments, jetties, piers, wharves, piles, and navigation aids, as well as 

 other less common structures. 



2. Background . 



There have been a number of excellent coastal engineering manuals and 

 guides that incorporate the best principles and criteria for design of coastal 

 structures that have evolved through several decades of experience and re- 

 search. However, most of these publications treat the subject of materials 

 adequacy lightly. An in-depth coverage of the pros and cons of each material 

 used would make these publications too unwieldy for efficient use. Thus the 

 subject is usually covered by references to a number of disparate and often 

 voluminous treatises on properties of materials, which places a heavy burden 

 of literature research on the design professional. Many of these treatises 

 cover aspects of the materials that have little relevance to coastal use in 

 addition to information of value to the coastal engineer. In some cases, the 

 reference may ignore unique effects of the coastal environment on the subject 

 materials. 



3. Objective . 



The objective of this publication is to condense the subject of materials 

 adequacy and suitability into a single document to support the coastal engi- 

 neering profession while eliminating the superfluous coverage. The study is 

 confined to the properties of those materials and treatments or variations 

 thereof that are applicable to coastal engineering structures. Emphasis is 

 placed on full coverage of materials that have proved most effective and long- 

 lasting in coastal structures. 



4. Organization of Report . 



Experience has demonstrated the success and failure of many materials used 

 in the past to create various types of coastal structures. In this report the 

 principal physical properties of these materials and their importance in the 

 selection of construction materials are set forth. New synthetic materials as 



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