improvements in the constituent elements of the defence structures against erosion and resulting structure and method of assembling thimble structure

摘要

The system protects river banks, beaches and dunes, from erosion due to wave damage and tidal currents. Double-shaped concrete blocks with interlocking edges are assembled on dry land. Each block incorporates a sleeve through which a galvanised steel cable is passed in )addition each block has a protruding tongue cast on the leading facing edge and an indented groove on the trailing edge. This arrangement provides positive location of adjacent reventment blocks. When sufficient blocks are connected the excess galvanised cable is trimmed and clamped at each corner. The carrying frame assembly is attached and the blocks transported with a crane to the installation area. The blocks are then lowered either onto a prepared permeable layer on suitable textile mat. A trench filled with concrete provides suitable anchorage at the top of the bank. The interlocking concrete blocks can be installed below the water level by this method the joints between the blocks can then be filled with sand. USE/ADVANTAGE - Cost effective installation procedure for flood damage and erosion protection which does not require lengthy training periods for labour force.