Design Manual for Articulating Concrete Block (ACB) Revetment Systems
This design manual provides guidelines and procedures for the design and installation of articulating concrete block revetment systems. Articulating concrete block (ACB) systems are used to provide erosion protection to underlying soil from the hydraulic forces of moving water. An ACB system is comprised of a matrix of individual concrete blocks placed together to form an erosion-resistant revetment with a geotextile underlay for subsoil retention.
The term “articulating” implies the ability of the matrix to conform to minor changes in the subgrade while remaining interlocked with or without the use of cables, geotextiles or geogrids. Several varieties of ACB systems are available: interlocking, cable-tied and noncable-tied matrices, and open cell and closed cell varieties. Open cell units contain open voids within individual units that facilitate the placement of aggregate and/or vegetated soil. Closed cell units are solid, concrete elements that are capable of allowing vegetation growth between adjacent units.
This 3rd edition includes the new Shear and Velocity design methodology for design velocities higher than 8 ft/s (2.43 m/s) on channelizing and overtopping projects. Use this design manual to ensure proper design and construction of ACB systems.
In addition to the Manual, NCMA has developed a design spreadsheet for ACB systems using the same methodology. Access the design spreadsheet here.