FRP Grating Load & Span Calculator
This calculator checks your span and load against MACHS load test data for molded and pultruded FRP grating. It rounds your span and load up to the next tested values and compares the measured deflection with your limit, so the result is conservative.
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CalculatedHow does this calculator choose a grating?
It rounds your span and load up to the next tested values, then compares the measured deflection with a limit based on your actual span. It never extrapolates beyond the table. Span matters: increasing a span by 1.5 times can produce roughly four times the deflection. Use the tested span rather than assuming a linear change.
Where a reading is missing, a higher-load reading at the same span can establish a passing upper bound. If that higher reading does not pass, the missing point stays “Not tested”; it is not marked as a failure.
What do the test loads mean?
The nominal uniform test loads of 2.39, 4.80 and 9.58 kN/m² correspond to approximately 50, 100 and 200 psf. Line loads are force per unit width, not a wheel or point-load check.
What the calculator does not cover
Point loads, wheel contact areas, cut-outs, high-temperature performance and breaking loads are outside this tool. The load tables are measured deflections under parallel two-side support conditions, not an ultimate-strength design.
Frequently asked questions
Which deflection limit should I use?
Your project engineer should set the limit for the application and applicable standard. span/200 is the default selection check; span/250, span/300 and a fixed millimetre limit are also available.
Why is my span “outside the tested range”?
There is no test span long enough for that model. Add a support or request more test data. A shorter tested span cannot validate a longer actual span.
Can I use this for forklift traffic?
No. Forklift wheels create concentrated loads. Send the wheel load, contact area and support layout for a separate engineering check.