C L DUBEY – EXERCISE – 08 (DRY DOCKING)

• When level is lowered by 1.5m the water level = 5.5m above. It means stern has already taken to the block while forward end is still afloat.

Change in draft aft = (5.5 – 6.20)m = 0.70m
70 =   P/17 +( P⨯70/150) ⨯70/144
P = 245.03 tonnes

GG₁ = P ⨯ KM/W
= 245.03 ⨯ 6.9/6220
= 0.272m

Virtual  GM = (Old GM – GG₁)
                = (0.7 – 0.272)m  
                = 0.428m

• When level is further lowered by 1.0m water level = 4.5m. Since water level is lower than hydrostatic draft ship has taken over block overall.

Then P = (TPC ⨯ mean rise)
= 0.679 ⨯ 100 ⨯ 17
 P = 1154.3 tonnes.

GG1 = (P⨯KM)/W
= ( 1154.3 ⨯ 6.9 )/ 6220
= 1.280m