Some preliminary considerations on the selection and durability of rock and concrete materials for breakwaters and coastal protection works

Abstract

Summary The durability of concrete and rock used in marine construction is reviewed. The marine environment has been divided into four significant zones of effect on the durability of concrete and rock. Forms of deterioration specific to concrete or rock and common to both are discussed in the context of the four zones. Rates of concrete deterioration in the zones and in different environments are also discussed. A preliminary study is presented of the shape, size and weathering characteristics on the performance of rock used in marine structures, particularly rubble-mound breakwaters. Nomographs for field use, relating the design weight of rock to shape, size and specific gravity are presented and acceptance and compliance tests for assessing suitability of rock are suggested. Design of filter systems is also considered in relation to rock characteristics for breakwater cores with high fines contents and for reclaimed areas behind coarsely graded protection works.