Platform Top Thickness Calculation

Hi!

I'm working on a project for a theater project where I'll be building a platform with projectors hidden underneath so that I can, with the help of some mirrors, project onto the surface of the floor from below. I'll be building the platform structure out of wood and the top will likely be polycarbonate, unless anyone has suggestions for less expensive transparent materials.

I'm running into difficulty remembering how to calculate how thick the polycarbonate must be to support 100 psf. I know this is something I learned way back in statics but now I've forgotten it and the internet is proving unhelpful. Any help is much appreciated!

Thank you!

-Syd

[FONT=maple-web]The allowable loads carried by walkways and platforms must not over stress the materials used in its construction. For steel walkways and platforms a rule-of-thumb is to limit the maximum deflection along a span to[/FONT]
[FONT=maple-web]Length of unsupported span / 250[/FONT]
[FONT=maple-web]This represents a 10mm deflection per 2.5 meters. The overall deflection for a span should be kept to a maximum of 10mm – 15mm. Greater deflections [B]scare [/B]people and they will consider the structure unsafe, though it is unlikely to be.

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