Acrylic windows under hydrostatic pressure, e.g.
aquarium panels, have to retain the massive water load of the water column in the tanks. In public and private tanks the safety of the viewer but also of the marine life should be considered as vital. The design engineer therefore has to limit the material's tension and the maximal deflection of the window in order to maintain safety regulations.
Choice of Material Thickness for Plexiglas©
The choice of material thickness or
the definition of the permissible water pressure is based on
theoretical calculations and confirmed by practical tests. On
request, the
thickness for a specific project can be determined and manufactured
according to your instructions. Our calculation of the required
sheet thickness under hydrostatic pressure (according to Girkmann /
Czerny) allows evaluation according to the
maximum material stress (s) and
maximum deflection (f).
The basis for this calculation are:
elastic modulus = 3300 MPa;
Poisson's ratio mb = 0.37; max.
safety stress spermiss. water side = 3 MPa,
air side = 5 MPa.
Detailed calculations by a structural engineer are required to
precisely determine the actual material stress at a given location.
The joints bonded call for special certification. In
this case, the maximum safety stress should be less or equal 3
MPa.
Typical Aquarium walls are between 30mm and 300mm (about 1'' and 1') thick.
Feel free to send us your preferred shape, width, height and water height over panel bottom, and we provide you with possible dimensions. Projects, that Hydrosight is directly involved in, are free of charge.
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