Stability Tests of Interlocking Block Revetment

Abstract

This paper is a report on the further development of light-weight interlocking concrete block revetments through tests in the Large Wave Tank at Coastal Engineering Research Center. Two types of blocks were tested on a 1 on 2 slope; one a machine-produced tongue-and-groove type weighing 75 lb, and the other a hand-produced shiplap type weighing 150 lb, the latter having twice the surface area of the former. In all, ten tests were made with wave heights ranging from 1.5 ft to 6.2 ft and wave periods ranging from 3.0 sec to 6.0 sec. Observations were made of the displacement of blocks and the vertical movement of the face of the slope when attacked by waves. Test data have provided information resulting in the development of a machine-produced block which remained stable under the continuous attack of 4.7-sec 4.8-ft breaking waves. Comparative tests showed that the tongue-and-groove blocks have greater stability than the shiplap blocks.