The Effect of Tide on the Planar Tilt of a Large Cylindrical Steel Tank

This paper is dedicated to clarifying the causes of an inadmissible planar tilt from hydrostatic testing on a large-scale cylindrical steel tank on an ocean airport. Using the finite element method, two factors, i.e., the soil’s non-uniform compressibility and the tide, are separately investigated to explore their effects on the planar tilt. In the finite element model, the tank is built on a foundation soil with three layers of non-uniform thicknesses. The results show that, as the water table remains constant, an apparent planar tilt of the tank is observed during hydrostatic testing, highlighting the effects of the soil’s non-uniform compression. The effects of the tide are considered by varying the water table as the tank is fully filled. The overly slight variation in the foundation settlement indicates that the variation in the water table (i.e., the tide) has negligible influence on the planar tilt.