1. ERDC Knowledge Core
2. Pre - Engineer Research and Development Center (ERDC)
3. Hydraulics Laboratory - (8/1/1972 - 9/1996)
4. Publication
5. Miscellaneous Paper

Title:	Concrete armor units for protection against wave attack : report of ad hoc committee on artificial armor units for coastal structures
Authors:	Hudson, Robert Y.
Keywords:	Armor units Stone armor Dolos Dolosse Shore protection Breakwaters Coastal structures Concrete armor units Rubble-mound breakwaters Shore protection Water wave forces Design
Publisher:	Hydraulics Laboratory (U.S.) Engineer Research and Development Center (U.S.)
Series/Report no.:	Miscellaneous paper (U.S. Army Engineer Waterways Experiment Station) ; H-74-2.
Description:	Miscellaneous Paper Abstract: A large number of special-shaped concrete armor units, for use in the protective cover layer of rubble-mound structures exposed to storm-wave action, have been developed throughout the world in the past 20 to 25 years. Quarrystone armor units may be used when available at a competitive price and when the wave conditions at the structure site are not too severe. The purpose of this report is to provide design information and guidance in selecting the shape and size of concrete armor units for use in constructing rubble-mound structures that will be stable at a minimum of cost. The factors that determine the choice of design waves are described; the development of a stability formula and stability coefficients for different amounts of damage to the structure are presented; the advantages of using high-density concrete in the fabrication of armor units are stressed; and the casting of armor units, the problems of breakage, and the legal aspects of using concrete armor units of special shape are discussed. Based on the results of test data available to date, it was concluded that the tetrapod, tribar, and dolos armor units should be considered for use in the design of rubble-mound breakwaters and jetties when the use of quarrystone is not feasible. The dolos armor unit is believed to be the most efficient, and procedures for the design of a typical breakwater cross section, using these armor units for the protective cover layer, are presented. The use of hydraulic model studies to determine the optimum design of proposed breakwaters is discussed. Appendices A and B present summaries of the Corps of Engineers experience in the use of concrete armor units, and flow diagrams for decision-making in the design of rubble-mound structures.
Rights:	Approved for public release; distribution is unlimited.
URI:	http://hdl.handle.net/11681/10792
Appears in Collections:	Miscellaneous Paper