Anuncios

The Autodesk Community Forums has a new look. Read more about what's changed on the Community Announcements board.

Sweep Along Curved & Sloped Path

cdannunzio
Explorer

Sweep Along Curved & Sloped Path

cdannunzio
Explorer
Explorer

Hello,

 

I am using AutoCad 2020.

 

I am trying to model a cast in place concrete ramp structure which is curved and has a 5% slop along the centerline. I was able to obtain the CAD file from the EOR to get the alignment and section of the structure. I took the 2D file and put vertical reference lines along the centerline to establish the correct elevation at each point. I then drew arcs and lines to establish the 3D alignment and converted to polylines to referencing when using the sweep function. 

 

I placed the section outline at the beginning of the ramp structure and used the sweep command along the centerline that I created. When I do this, I end up with a rotation on the solid. This structure is intended to be "level" across and not super-elevated. I split the structure into three sections (first curve (W4 to W3), straight section (W3 to W2), second curve (W2 to W1)). This rotation seems to only be occurring at the first and second curves.

 

Once I have the CIP section modeled, I wanted to use this to determine "fills" required from the falsework (not modeled) that will be provided to support the formwork for the ramp structure. I was thinking maybe the best way to do this would be to create a planar surface to represent the top of falsework and dimension from this surface to the underside of the ramp structure. (Maybe there is a better way to do this). 

 

The working portion of the model is all the way to the right of the model space in the attached file. You should be able to see the rotation at W3 when referencing the green section I drew that is level. Any help is greatly appreciated. I have worked with 2D, but am clearly inexperienced with 3D. 

 

cdannunzio_0-1588777951778.png

 

0 Me gusta
Responder
1.660 Vistas
3 Respuestas
Respuestas (3)

R_Tweed
Advisor
Advisor

Is the section intended to be perpendicular to the centerline?  I made an array of the sections based on the centerline as a path and then used the loft command to model each part. A revised version of your file is attached.

 

 

Annotation 2020-05-06 171256.png

0 Me gusta

cdannunzio
Explorer
Explorer

Yes, the section is supposed to be perpendicular to the centerline. At first glance, it looks like you did it! Thank you very much for your help.

 

After you completed the array command, did you explode it and loft from section to section within the array? It seems like there would be a way to loft from section to section without manually clicking down the whole line of array items. I tried to recreate your steps and created an array with a small spacing between items and then started to loft between each section, just seemed really repetitive.  Does it matter what the spacing is of the array prior to doing the loft command? I want to make sure I know exactly how you did this for future reference.

 

Also, do you have any ideas on how to create an arbitrary surface (or multiple) to represent the top of falsework? There will be falsework towers with header beams at locations along the curve with straight beams between them (provided by others). I am trying to determine the elevation they need to set their header beams/longitudinal beams to in order for us to build the ramp to the correct elevation.

 

cdannunzio_1-1588855028939.png

 

 

 

 

0 Me gusta

R_Tweed
Advisor
Advisor
After you completed the array command, did you explode it and loft from section to section within the array?
Yes. I used an odd number of sections to match up with your samples.  I think I used 7 at the top. The number of sections I used was meant to assure myself of the sampling. you should isolate each section and verify that they are perpendicular to the centerline for accuracy. ( I did not do that in my example)

It seems like there would be a way to loft from section to section without manually clicking down the whole line of array items. I tried to recreate your steps and created an array with a small spacing between items and then started to loft between each section, just seemed really repetitive.  Does it matter what the spacing is of the array prior to doing the loft command? I want to make sure I know exactly how you did this for future reference.

 

Also, do you have any ideas on how to create an arbitrary surface (or multiple) to represent the top of falsework? There will be falsework towers with header beams at locations along the curve with straight beams between them (provided by others). I am trying to determine the elevation they need to set their header beams/longitudinal beams to in order for us to build the ramp to the correct elevation.

 

I would draw and align a rectangle under each section and loft it as well, model your beams and columns under that and use the array command along the centerline.  Let the column run longer than needed and use the slice command to trim off the excess at your base elevation. To create the guides for your top of beams you could use the imprint command.

 

 

 

 

 

 


 

0 Me gusta