FUEL TANK FOUNDATION IMPROVEMENT SYSTEM ON SOFT SOIL LAYER BASED ON 3D NUMERICAL SIMULATION

Abstract

Differential settlement on the fuel tank storage foundation in Banjarmasin fuel depot,
Indonesia, cause the tilting of fuel tank storage. Due to this condition, the volume measurement of fuel in the
tank becomes inaccurate and difficult to be predicted. This problem affects the fuel distribution in
Banjarmasin area if not immediately solved. The structure of tank foundation was built on the soft soil
without another support structure. This research carried out the study on improvement of foundation structure
system with concrete slab supported by piles on the outside around and “Sistem Cakar Ayam” that spread
evenly in the area of the foundation. The numerical study of the proposed improvement of structure model
was conducted using SAP2000 and ABAQUS. The vertical and horizontal spring elements were chosen as

the support system on the foundation model in SAP2000. In ABAQUS, the model defined as a three-
dimensional model. The soils idealized by elasto-plastic Mohr-Coulomb model. The slab, piles, and

“Sistem Cakar Ayam” defined as elastic material. Based on the numerical analysis results, the analysis using
SAP2000 are used to determine the optimum configuration of the pile and there is no excessive differential
settlement. A three-dimensional numerical analysis using ABAQUS can represent actual field conditions
because the boundary conditions in two-dimensional analysis can be reduced. Reduction of deformations
using the proposed system is 70.79%. The proposed foundation system using slab supported by piles and
“Sistem Cakar Ayam” are quite effective in reducing the differential settlement due to fuel tank load.