INTERACTION ANALYSIS FOR OIL STORAGE TANK ON MARINE CLAY

The engineering behavior of marine clay is very different than that of the moist and dry clay because of its structural and mineral composition [1]. Marine structure is subjected to the waves which create a cyclic stresses inside the soil mass [2]. The huge storage tanks experiences a heavy wind and current load which produces a adverse effect in the soil settlements. In this paper a cylindrical reinforced cement concrete tank with diameter 100 m and 40 m height founded on soft marine clay of undrained shear strength of 10 kPa is considered for the analysis. The huge pile group is modeled by equivalent pier method and interaction factor method for the full and empty loading conditions. Settlement including the soil pile interaction has been estimated for both the cases mentioned above for different pile configuration including pile length, diameter and spacing of piles in a group. It has been observed that the spacing of the piles plays a vital role in estimating the settlements and stresses. With the comparison of the equivalent pier method (EPM) [8] and interaction factor method (IFM) for settlement estimation, the later is found to be more suitable for interaction analysis to achieve the safety of the tank.