User Defined Load

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anderscd9
User Defined Load

Is it possible to import user defined loads instead of manually entering through the program?

Pickings
Currently there is no way to

Currently there is no way to import loads data into the program although this is a feature we could add to the Pro package if there is enough demand. What kind of load data would you like to import, where is is coming from, and what format should it be in?

Regards,
Richard

Richard Pickings, P.E.
BridgeSight Inc.

anderscd9
TxDOT requires haunch to be

TxDOT requires haunch to be input as user defined dead load. This results in inputting user defined trapezoidal loads on each girder. This input could come from a simple text file where Type, Stage, Load Case, Span, Girder, Location, and Magnitude are defined.

Pickings
You may not need this feature

You may not need this feature soon. TxDOT is currently funding a project to deal with camber and the application of haunch loads using their methodology. The camber capability will be part of PGSuper version 3.0. when it is released (date, YTBD). However, a generalized load input may be useful for other purposes.

Richard Pickings, P.E.
BridgeSight Inc.

jdarr02
haunch loads

This is kind of an old post, but I thought I'd respond here before creating a new question in the forum.

I have version 3.1.2.0, and it has a "Haunch Geometry" section (in the "Deck Geometry and Materials" tab of the Bridge Description. When you give it the "X" dimension, and view the bridge's cross section at various locations along the span, it shows that the haunch decreases midspan, and increases at the end due to the camber. So this leads to 2 questions...

1) I used to tell PGSuper my minimum deck thickness (which it would use to convert to the deck dead load), and input the haunch dead load as a uniform user defined load. Now that the program knows I have a haunch - is it applying the corresponding dead load?

2) PGSuper used to think that my deck was always right on top of my beam. This led to a conservative design because the actual moment of inertia was always larger than what PGSuper calculated. Now that it knows there is a haunch, is it increasing the moment of inertia where the haunch is > 0?

Thanks in advance for any help!
-Joel

Professional Nerd.

jdarr02
There are no stupid questions. Only stupid people.

Aaaaaaand I'm one of those stupid people.

I just saw under "graphs" ---> "Analysis Results" that there's a Haunch category, so obviously, PGSuper is now doing that for me.

I'm still not sure about the increased stiffness issue though. I did find in the "Details Report" under "Section Properties" that it just gives Ix and Iy for the girder itself and the composite section (rather than having something like a table of these values at points along the span) which would lead me to believe it's still computing these values the conservative way.

If anyone could verify this though, I'd be grateful.
Thanks!

Professional Nerd.

Pickings
jdarr,Don't beat yourself up

jdarr,
Don't beat yourself up - the way(s) pgsuper deals with haunch loading and structural properties is evolving as I type this message. The upcoming Version 3.1.4 (out in a few weeks) will provide a new way to model haunch loading due to the parabolic change in haunch depth caused by girder excess camber. The WSDOT assumption of zero excess camber will still remain in the program as well. The program has for a long time considered "A" dimension effects and roadway variations when computing haunch load.

From the beginning, and for the meantime, PGSuper will not consider the haunch when computing structural properties (stiffness, ultimate strengths). The current (usually conservative) assumption is that the composite slab sits directly on the top flange of the girder. However, a future version, coming out around Summer 2018, will allow optional modelling of haunch when computing composite properties and strengths.

I highly recommend reading PGSuper's Technical Guide to gain understanding about bridge modelling and loading assumptions. The assumptions work for most normal bridges, but for complex structures your mileage may vary.

Richard Pickings, P.E.
BridgeSight Inc.

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