Hello,
I am running spread analysis using ORD Utilities and Drainage workflow. Since this is our first project with the software, we are back checking its results with our trusty Excel sheets that are set up for spread analysis.
For our spread calculations, we use the following equation (From FDOT drainage design guide) to calculate our spread, and conservatively ignore gutter depression depths for curb inlets per the design guide. The utility information dialog seems to have no option to ignore gutter depth for curb inlets, which is causing some issues. Is there somewhere in the program to conservatively omit the gutter depth?
Thanks,
Emily
Under the physical properties you should be able to set depressed gutter to false.
Thanks for reply Matt. The depressed gutter is set to false. Do you think the issue I am having is that there is a catalog gutter associated with the inlet prototype, since its a curb inlet?
There is no way to turn off. But if I change the gutter slope the spread results change. Setting the catalog gutter to "none" errors out the drainage analysis.
Try to change the gutter type to user defined.
Based on your screen shot, you are using a conventional gutter with no gutter depression. This is a straight-forward application of the FDOT equation you posted, which is identical to the equation that ORD uses - they are both taken from HEC-22 (FHWA). So, ORD should give you the same results as your spreadsheet. Double-check that your spreadsheets are using the same values for Q, n, Sx, and Sl that are reported by ORD. In an example I just ran using a conventional gutter with Q=0.33 cfs, n = 0.015, Sx=2%, and Sl=3.68%, ORD reported a spread of 3.64', which is the same result from the HEC-22 equation.
Karl Dauber, PEAdvance ConsultingLaurens County, SCkarldauber@advconsult.netwww.advconsult.netwww.linkedin.com/in/karldauber