📖 Explanation
Given: w=15 S=67 e=0.6 Gs=2.67 V=5 m3 γw=9.81 kN/m3 To fully saturate the soil, we need to bring degree of saturation S from 0.67 to 1.00. Volume of voids per unit volume of soil: Vv=1+ee=1+0.60.6=0.375 So in 5 m? of soil, total void volume: Vv,total=0.375×5=1.875 m3 Currently 67% of voids are filled with water, so water volume present: Vw,present=0.67×1.875=1.25625 m3 To fully saturate: Required water volume = Vw,required=1.875−1.25625=0.61875 m3 Weight of required water: Ww=γw×Vw,required=9.81×0.61875=6.07 kN Rounded to nearest integer: 6 kN