Strands Locations

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Visitor (not verified)
Strands Locations

we are having difficulties in figuring out Strands locations
the plans only are providing strands eccentricities Cg(1) and Cg(2)

any ideas that might help us ?!

jruby411
Well, if you know the beam

Well, if you know the beam shape, you should have an idea of the template location for the available strand pattern. Then it is just a matter of adding strands from the bottom until the eccentricities match. I know it is an iterative process, but you can make an educated guess to start with.

Say your end eccentricity is 4 inches, you have rows spaced at 2 inches, the first row starts 2 inches from the bottom, my guess is the bottom 3 rows are full.

Jeff.

Nayef (not verified)
Thanks Jeff.

Thanks Jeff.

Rick Brice
I am guessing that cg1 and

I am guessing that cg1 and cg2 locate the strands at the end of the girder and the harp points. An alternative approach is to define the strand layout so that all strand locates are at the CGs. This approach only works for a fixed number of strands.

Nayef (not verified)
This is correct cg1 locates

This is correct
cg1 locates the harped strands eccentricity at the end of the girder
cg2 locates the straight strands eccentricity at the end of the girder

fixed number of strands ?! , does this mean if we have different girders each girder have a certain number of strands ?! we are having this case and we fixed it by defining a unique section in the library for the different girders

Pickings
Yet another possibility is to

Yet another possibility is to make all strands harped and locate all strand points at the same location (say, 0.0, 2.0). Then, in the library, allow the harped strands to be adjusted vertically both at the ends and harped points. This will allow you to directly place the CG (or eccentricity) anywhere you want with any number of strands. The girder design dashboard in PGSuper Pro makes this especially easy.

The danger with this approach is that you can easily create unconstructable strand layouts (e.g., 100 strands at 2" from the girder bottom). As an engineer, I prefer inputting real-life strand layouts that I know can be fabricated.

Richard Pickings, P.E.
BridgeSight Inc.

Nayef (not verified)
so we are actually adjusting

so we are actually adjusting the program to fit with our needs, we had this problem with the sidewalks.

we have a sidewalk of width 6' at one side of the bridge and we have shoulders at both sides of the bridge which are not counted to be a part of the sidewalk and used by bicycles, yet PGSuper requires defining a sidewalks to include pedestrian and bicycle loads in the calculations of loads.

is PGsuper Pro separating between bicycle load and pedestrian load and does it have the option of defining only shoulders ??.

Pickings
Neyef, PGSuper Pro does not

Neyef,
PGSuper Pro does not have any unique capabilities compared with the basic PGSuper with respect to sidewalks and barriers. You may need to directly input the loads to get what you want. Refer to the section called Standard Loading in Chapter 5 of the user for a detailed description of how sidewalk and barrier loads are distributed.

Richard Pickings, P.E.
BridgeSight Inc.

Nayef (not verified)
Thanks and Appreciation

I'ld like to thank all of you , you really helped us.

I'ld like to post our procedure that might help others having the same problem.

we chose to compare our beam section with the nearest wdsot section to try figuring what is actually the suitable real-life strand layout that can be fabricated and by trial and error we eventually got the correct eccentricity.

some problems appeared while we were adding harped strands :

1.at the mid span a bundle of harped strands should be existed and we solved this problem by making horizontal and vertical spacing equal to zero and we set the provided eccentricity for these strands.

2.due to existing of a bundle of harped strands at the middle we set the x-coordinate of the first straight strands to 2.25" -we obtained this value to nearest WF wdsot section.

hope this was useful for some of you Inshallah

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