--> //initilizations

--> n=0.4//(porosity)
 n  = 

   0.4


--> G=2.65//(specific gravity)
 G  = 

   2.65


--> w=0.12//(water content)
 w  = 

   0.12


--> Vs=1//m^3 (assumed unit volume of solids)
 Vs  = 

   1.


--> Dw=1000 // (unit weight of water)
 Dw  = 

   1000.


--> //calculations

--> Ms=G*Dw //(mass of solids)
 Ms  = 

   2650.


--> Mw=w*Ms //(mass of water)
 Mw  = 

   318.


--> Vw=Mw/Dw //(volume of water)
 Vw  = 

   0.318


--> e=n/(1-n) //(void ratio)
 e  = 

   0.6666667


--> Vv=e*Vs //(volume of voids)
 Vv  = 

   0.6666667


--> Va=Vv-Vw //(volume of air)
 Va  = 

   0.3486667


--> V=Vs+Vv //(total volume of soil)
 V  = 

   1.6666667


--> Vr=(Va*100)/V //(volume of water required for 100 m^3 of soil)
 Vr  = 

   20.92


--> Mr=(Vr*Dw) //(mass of water required)
 Mr  = 

   20920.


--> //result

--> printf('mass of water required =%f',Mr)//kg 
mass of water required =20920.000000
