(b) Secondary Cover Layer . The weight of the secondary cover layer 



W 



— is based on the weight of a primary cover layer made of rock. W . 

 10 " 



PRIMARY 

 COVER LAYER 



SECONDARY 

 COVER LAYER 



UNDERLAYER 



W = weight of primary cover layer if it were made of rock 



W 



-j-^ = weight of secondary cover layer 



w = unit weight of rock = 25.92 kN/m" 

 r 



K =4.0 for stone under nonbreaking wave conditions 



W metric tons = 

 R 



w H" 



V 



gK /S - 11 cot 6 



(c) Thickness of Cover Layer . Primary and secondary layers have the 

 same thickness. 



/g W 



r = n k, 4 



A A V w 



1/3 



(eq. 7-121) 



8-58 



