Optimum Design of Oil Tank Foundation on Different Soil Conditions

Tank foundation is a base for the tank which is designed to support the weight of oil tank in order to ensure its stability. Failure of tank foundation usually occurred when the foundation system cannot support the weight of the tank or the soil bearing capacity of the area failed to resist the imposed stress from oil tank inclusive of foundation’s self-weight. Failure of tank foundation can lead to pivoting effect and cracking on the foundation slab. Hence, the right choice of foundation system with reference to the bearing capacity of foundation soil is important to ensure the stability of tank foundation. Thus, this study was carried out in order to determine the deformation characteristics of foundation slab of oil tank foundation on different soil conditions with the aim to determine optimum design of oil tank foundation. The dimensions and design of the models were based on a published case study. Series of analyses with finite element models were conducted using STAAD Foundation CONNECT Edition V9. The models were aimed to analyze the stability of foundation structure, and deformation characteristics of the foundation slabs on different soil conditions. Three types of foundation system (raft, pile raft and pile foundation) were modelled in STAAD Foundation CONNECT Edition V9. The findings showed that the most optimum design for foundation structure on stiff residual soil is raft foundation. Whereas pile raft foundation structure is the most appropriate to construct on unconsolidated marine sediment deposit while pile foundation structure is highly recommended on soft peaty soil.