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If “variable” is selected ETCulvert Eriksson Culvert will select the most efficient thickness for each member during the design process. Note that next to this option is “Min. Thickness”; by specifying a value for this, ETCulvert Eriksson Culvert will not select a member thickness smaller than this value. You may input 0 here, in which ETCulvert Eriksson Culvert will use a minimum of 3”.
If “fixed” is selected ETCulvert Eriksson Culvert will not size the member, and instead use the value specified in the “Thickness” option. Note that the minimum thickness you can enter is 3”.
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