Beam Troubles

[BunyipCatcher]

Good morning all,

Iam playing with the demo and need a bit of help with a couple of things. I have attached a small jpg, to show what I mean.

I cannont figure out how to get the ends of my concrete beams to be dimensionally accurate. Any ideas on what Iam doing wrong. The only way I could get the ends somewhat close to where the slab edge is, was to draw a **** grid and snap to that. But as you can see its still 13mm out.

How can I get supporting structue below to show as hidden. In this example the column is below?

How can I get the edges of the beam to show hidden where they meet the 250 slabs?

Any help is appreciated.

Scott V

[rmcelvain.103137]

Scott,

I'm swamped at the moment, I'll try and look into what your having happen hopefully a little later this week. Don't give up on us :) !

[BunyipCatcher]

No worries mate,

Im swamped too. So its back to AutoCAD.

Ive spent more time trying to figure out how to get the ends to be right than drawing the little I have already drawn.

Cheers

[Paul Andersen]

Scott, I've found that the align tool comes in handy when doing concrete work. If you are laying out the columns and beams first and know that the beam end is 2'-0" off of the gridline I will generally slop the beam in there from column to column draw a temporary reference plane with a 2'-0" offset, align the beam end to it, and then delete the reference plane. If you have other geometry already established such as a slab edge or other beam end you can also use those for alignment. The nice thing about aligning the beam end to a slab edge or other member is that you can lock the relationship and if the slab edge moves the beam end will adjust automatically. (Note: changing the beam end will result in a Constraints are not satisfied error if locked to a slab edge since it cannot adjust the slab sketch). Some beam families like the Precast-Inverted Tee also have Start and End Extension parameters that can be adjusted in the properties dialog.

Showing columns hidden under slabs or beams is typically automatic in RS. First thing to check is that your view is set to hidden line mode. Second thing to check is that your column top elevation is set to be below the beam or slab it is supporting. Third thing to check (which is the one I usually find is the culprit) is to adjust the line pattern under object styles to be something other than dash for the column hidden lines. The dash in this pattern is typically too long to display any breaks at typical plan scales. To adjust the line pattern go to Settings -> Object Styles and in the Model Objects Tab expand the Structural Columns tree and change the Hidden Lines Line Pattern to whatever displays to your liking.

Monolithically poured beams and slabs pose a slight display challenge with regards to hidden lines. Lets say you have a 32" deep beam from slab top to bottom of beam and a 6" thick slab. One method is to cheat the beam depth or elevation offset from top of slab by a fraction of an inch (1/256" will work). A second method is to use a 26" deep beam (32"-6") placed below the 6" slab and join geometry. The benefit of these two methods is that RS will handle the hidden line display in plan automatically. The downside and reason I don't use these methods is that the model is not dimensionally accurate. The method I prefer and currently use is to model everything accurately (32" deep beam with it's top the same as the top of slab) and then use a combination of join geometry and the linework tool to clean things up.

The linework tool when used with hidden or invisible lines can clean up most issues that RS doesn't handle automatically. While I generally use it as a last resort it does come in handy. The line between your two beam ends could be cleaned up with invisible lines. Keep in mind that with structural members that have top and bottom lines displayed in plan it is often necessary to click more than once. Also if one beam were wider than the other join geometry between the two first before cleaning up the ends with the linework tool or the entire line that defines the end of the wider beam will disappear as opposed to the line they have in common. Hope this helps and apologies for the delayed response.

[BunyipCatcher]

Paul,

Thanks for your reply and being clear. Even if it was in feet and inches. ;-) I have finally got a plan looking something like what I already have in AutoCAD.


Scott, I've found that the align tool comes in handy when doing concrete work. If you are laying out the columns and beams first and know that the beam end is 2'-0" off of the gridline I will generally slop the beam in there from column to column draw a temporary reference plane with a 2'-0" offset, align the beam end to it, and then delete the reference plane.
Tried you reference plane idea and works. I can then snap to the intersection of the reference plane and the gridline.

But it the rectangular beam still protrudes 13mm if just drawn by itself. I think this is so that it will fillet properly with beams of the same type. Thats how it looks to me.

I still cant get the extensions of the inverted t beam to snap to anything graphically. I have to work out a dimension and its a real pain.


Showing columns hidden under slabs or beams is typically automatic in RS. First thing to check is that your view is set to hidden line mode. Second thing to check is that your column top elevation is set to be below the beam or slab it is supporting. Third thing to check (which is the one I usually find is the culprit) is to adjust the line pattern under object styles to be something other than dash for the column hidden lines. The dash in this pattern is typically too long to display any breaks at typical plan scales. To adjust the line pattern go to Settings -> Object Styles and in the Model Objects Tab expand the Structural Columns tree and change the Hidden Lines Line Pattern to whatever displays to your liking.
Yup thanks for that created a linetype matching the one I have in AutoCAD and it works fine.



Monolithically poured beams and slabs pose a slight display challenge with regards to hidden lines. Lets say you have a 32" deep beam from slab top to bottom of beam and a 6" thick slab. One method is to cheat the beam depth or elevation offset from top of slab by a fraction of an inch (1/256" will work). A second method is to use a 26" deep beam (32"-6") placed below the 6" slab and join geometry. The benefit of these two methods is that RS will handle the hidden line display in plan automatically. The downside and reason I don't use these methods is that the model is not dimensionally accurate. The method I prefer and currently use is to model everything accurately (32" deep beam with it's top the same as the top of slab) and then use a combination of join geometry and the linework tool to clean things up.

The linework tool when used with hidden or invisible lines can clean up most issues that RS doesn't handle automatically. While I generally use it as a last resort it does come in handy. The line between your two beam ends could be cleaned up with invisible lines. Keep in mind that with structural members that have top and bottom lines displayed in plan it is often necessary to click more than once. Also if one beam were wider than the other join geometry between the two first before cleaning up the ends with the linework tool or the entire line that defines the end of the wider beam will disappear as opposed to the line they have in common. Hope this helps and apologies for the delayed response.



Yup I have been using these for everything. Gets the job done. Although its hard to remember what I have joined to what.

Thanks again for the help. I have more questions now but about other things.

Scott V

[Paul Andersen]

Scott, I think you're right about the 13mm. There is an extra 1/2" extension built into the imperial family. This only comes into play with regards to placement or dragging the end however. Using the align tool to other geometry or ref planes should be right on. Is that not the case for you?

With regards to the inverted tee issues I'm assuming it's a problem at time of placement. Is that correct? The align tool or tweaking the extension parameters in the properties should help. The drag handles can be useful but not always for precise placement. You can also hover over the end of the tee and tab so that you only highlight the end of the tee. Once you select the end you can use the move command in conjunction with the temporary dimensions to locate the end precisely.

I need a unit converter button on the posting toolbar for replying to you metric guys :) .

[BunyipCatcher]

Scott, I think you're right about the 13mm. There is an extra 1/2" extension built into the imperial family. This only comes into play with regards to placement or dragging the end however. Using the align tool to other geometry or ref planes should be right on. Is that not the case for you?.
I didnt understand what you meant by align. The align tool. Yup I have given it a go, and it works. They only thing is I have to remember to get rid of this pain in the ..... extension of 12.5mm before the align works.

Thanks again for your help. That makes it a lot easier.

[BunyipCatcher]

Now I have another problem. See attached pic file. I cant get these three different beams to come together. I can get two as I have it. But if I try and align the face of the small L shaped beam with the horizontal reference plane I have I get the second attached pic.

Does it have to do with the fact that the beams that come in hatched are PC concrete and the rectangular horizontal beam is insitu concrete????

Scott V

[Paul Andersen]

Hopefully the example I have chosen is your desired outcome. I've experimented with several ways to get the desired outcome graphically but have found only one method that appears to keep the analytical model intact. Because your are essentially using two different beam types that handle end alignment differently the process isn't as straight forward as it probably could/should be.

Step 1 - after your columns are placed and beams are added (by whichever methods you prefer) you should wind up with something similar to the Step 1 image. Note: at this point my top of column and top of beams are at the same elevation.

Step 2 - the align tool can cause some issues when adjusting certain beam ends so I would recommend hovering over the end of the Precast L beam that you wish to adjust and hit the tab key until just the end highlights (should be one hit of the tab key) and then left click to pre-select the end. Now you can use the move command (shortcut MV or selecting from the button bar . . . not the mouse click drag method) You should be able to accurately move the end of the beam to line up with the edge of the concrete beam. Repeat with the other Precast L and you should wind up with something similar to the Step 3 image. The benefit of this method is that you can accurately and graphically adjust the beam extension without disturbing the analytically model.

Step 3 - at this point I adjusted all of the column heights to be equal to the bottom elevation of the beams. This could be done at any point up to Step 4 but the columns need to be correctly located prior to adjusting the concrete beam or you may run into some constraint issues between the concrete beam and the column.

Step 4 - using the align tool select the back edge of the Precast L and then the end of the concrete beam. This should have the intersection looking pretty good at this point. Note: while you are adjusting the beam ends to make this intersection work you may have to readjust the opposite ends of the beams.

Step 5 - using the align tool select the front edge of the wider Precast L and then the front edge of the narrower one and hopefully this is what you were after. I've attached a 6th image to show that the analytical model has remained intact.

When dealing with beam ends I will typically use the move method described in step 2 for any member with drag handles (Note: the triangular drag handles not just the round end grip) and the align tool for members without drag handles. Note: the align method used on the end of the concrete beam only works well for one end. You will need to contend with 13mm issue on the other end in a different manner. It would be nice to get some insight from someone in the know about what this extra 13mm (1/2") is really for. I agree with your assumption in that it probably aids in the joining with other members. If I get some more time I will see what happens when it's removed from the family. May be worth having a family on hand without this added extension for placement situations such as these.

I would also refrain from locking the alignments as the model can quickly become over constrained resulting in pesky errors down the road. That being said you will need to tweak intersections such as these if any of the member sizes change.

I slapped this together rather quickly so if you can't get this to work due to missing information or poor explanation let me know.

[BunyipCatcher]

Thanks Paul for the reply havent had time to give it a burl yet. Will get some time soon. And let you know how it goes.

Scott V

[ryanmcin]

[QUOTE=Paul Andersen]You will need to contend with 13mm issue on the other end in a different manner. It would be nice to get some insight from someone in the know about what this extra 13mm (1/2") is really for. I agree with your assumption in that it probably aids in the joining with other members.[QUOTE]

I seem to remember being told that it is required for the cope command to work properly.