Sumitomo Mitsui Construction (SMC) has launched Floating Net, a type of damping equipment that prevents oil from sloshing around in tanks during long seismic waves.
During the Tokachi-Oki earthquake in 2003, some oil storage tanks with floating roofs were badly fire damaged. This was caused by the oil overflowing from the resonant motion induced by the seismic waves.
SMC developed Floating Net to decrease the sloshing wave height by setting up a frame with a floating net right under the floating roof of the oil storage tank. This passive response control system controls the sloshing wave height using the fluid resistance power generated when the liquid passes through the apertures in the net.
The best dimensions for the net and the apertures in it were confirmed through seismic table experiments.
According to feasibility tests, Floating Net doubles the damping effect when attached.