This award will allow Professor William G. McDougal, Oregon State University, to collaborate with Professor Hans F. Burcharth, University of Aalborg, Denmark. They will study the strain resistance characteristics of the dolos armor unit. Such units are used to provide protection against wave induced forces for shorelines, jetties, and breakwaters. Traditionally, large stones have been used to make rubble structures to form the protection, but as construction has been extended into increasingly hostile wave environments, the necessary weight of hydraulically stable stones becomes unreasonable. Such stones are hard to find and to handle. As an alternative to stones a variety of armor units have been developed. The dolos has received considerable attention, because it has a high hydrodynamic stability coefficient, it's units interlock well, and it is relatively porous, but it is also susceptible to structural failure. The proposed research will test dolosse for strain under a variety of simulated conditions. Professor McDougal is one of the few U.S. engineers studying this problem, and Professor Burcharth is an international authority on concrete armor units. It is necessary to conduct the research at Aalborg University, because the test dolosse are there. They would be expensive to move or to construct in the U.S.
