Volume 37, Issue 2 (March 2009)
A Novel Setup for Testing of Ship Deck Stiffened Panels under Axial and Lateral Loads
A novel setup for testing of stiffened panels in ship decks subjected to axial and lateral loads is developed in the Department of Ocean Engineering, IITMadras. The entire setup consists of self-straining test rig, imperfection measuring device, displacement controlled hydraulic jacks, rigid grillage, inflatable air balloon with and without opening, and a data acquisition system. The fabricated deformable test rig replicates similar boundary conditions along the loaded and unloaded edges of stiffened panels in between transverse stiffeners of a ship deck. An imperfection measuring device located on the test rig is designed and fabricated to measure geometrical initial imperfections on the plate and stiffener. A unique displacement controlled twin hydraulic jack system is developed to apply axial load on the panel. A rigid grillage connected to the bottom of the test rig to act as reactive support for the application of lateral load on the panel is fabricated by performing static nonlinear analysis using ANSYS. An inflatable air balloon with and without opening is fabricated to simulate constant cargo (lateral) load acting on the panels. The applied axial load and produced axial deformation measured by load cells and LVDT, respectively, is plotted simultaneously while testing using an integrated data acquisition system. Nonlinear finite element analysis of tested specimens is performed using ANSYS to compare the ultimate load obtained from experiments. A close agreement between the experimental data and finite element analysis results indicates realistic simulation of truly combined axial and lateral loads with deformable supports acting on stiffened panels as in ship decks achieved in the laboratory and numerically.