APPENDIX A: NOTATION 



a Wave amplitude 



a ir Sum of incident and reflected wave heights 



A Q Orbital diameter of wave motion 



A s Projected area of a sediment grain 



B a P ron Apron width 



C Initial sediment concentration for use in MacDonald's (1973) sediment 

 concentration equation 



C x "Shape" coefficient 



C 2 Drag coefficient 



C A Known concentration at height A above the bed 



C D Drag coefficient 



C s Sediment concentration in the water 



d Arbitrary representative particle diameter, typically mean or median 



d x Depth from still-water level to top of toe for stable rubble-mound 

 structure using Markle (1989) guidance 



d e Equivalent effective bottom roughness 



d Median grain diameter 



d E Depth from still-water level to sediment base on which rubble-mound 

 structure resides using Markle (1989) guidance 



d u Uniform grain size 



D Drag force 



D Pile diameter 



f f Friction factor for use in Prandtl's chart 



f w Friction factor for wave motion on bottom 



Fr Froude number, V/(gL) % or U/(gL) % 



g Acceleration due to gravity, 32.2 ft/sec 2 or 9.8 m/s 2 



h Depth 



h 1 Depth used in Sawaragi's equation for breakwaters 



h 2 Depth used in Sawaragi's equation for breakwaters 



h b Depth of water at point of wave breaking 



h c Critical water depth 



h u Depth of uniform flow 



h„ Depth of water in front of seawall 



H Wave height 



H Deepwater wave height 



H b Breaking wave height 



H c Critical wave height 



H D Design wave height 



H i Incident wave height 



H p Vertical distance from center of pipe to maximum scour depth 



H r Reflected wave height 



H s Standing wave height 



H so Deepwater significant wave height 



Al 



