irregular cruise vault with autocad

[Cloe85]

Bye to all,
I am new to the forum, I just enrolled after several attempts not gone to good end for the modeling of once on an irregular cruise with autocad for my specialist thesis.
the problem I find in modeling is this:
the vaults that I have to model cover spaces that instead of being square are trapezoidal plant; the arches at the ends of the time therefore have different diameters and are not parallel between them to two to two. I have followed many tutorials on the internet but they all describe procedures to make regular cruise times, and when I try to use the procedures for modeling my time do not go well. the time I have to model also I need to be exported on a seismic analysis program (straus 7) and therefore it should not be realized as a surface but as a full volume (i.e. producing the structural thickness of the turn equal to 30 cm) and then be joined to the lateral walls since the model I have to import on straus must consist of a unique volume. the specific because in the various attempts I made I was able to create an irregular time but when I went to join it on the walls with the command me solid the program gave me the error message "obsculation of the curves at the top", that while looking on the internet I was not well able to understand in what it is.
I hope someone knows how to help me, I attach an image of the environment in which the vaults are located on a cruise (trapped in red the projections of the diagonal arches and ends) Thank you very much to anyone who answers!

 

[GP.]

provided that on trapeze-shaped surfaces the result will not be perfect, I would do in this way:

- draws the trapezoidal plant with the two diagonals
- in view 3d draws vertical lines, corresponding to the height of the vault, in the middle point of the boundary lines and in the center of the diagonals
- positioned, from time to time, with the vertical bird on the boundary lines and on the diagonals, then draws the perimeter and diagonal arches
- breaks diagonal arches on the center
- for convenience copied out of the model the elements of the four nails (in the example below I reported only one)
- join the two diagonal arches (they will form a spline)
- loft, selecting as cross sections the perimeter arc and the spline created before
]

Amen

 

[Cloe85]

Hello gp, thank you for the answer!
the point to which you arrived is the same to which I had arrived with a different procedure (drawing of the 4 lateral arches with the procedure that you described ---> creating two lofts corresponding to the two barrel vaults that generate the vault to cruise, realized as an end of each loft two opposite arches between them ----> intersection of the two lofts).
My problem is that since the model doesn't need me to produce images but to make a structural calculation I can't, starting from this surface, generate the thickness of the time.
I tried both with the offset of surfaces and their extrusion but in both cases the result is not good. in the first the volumes intersect in a strange way, while in the second the thickness of the time varies and therefore from the structural point of view it is not correct!
Moreover in both cases I can not combine the volumes of the nails, which is indispensable for me since the overall file must be composed of a single volume so that the seismic analysis program in which I have to import it correctly generates mesh.
I attach the image to both wireframe and realistic view of the evidence if I didn't explain.Thank you so much!

 

[GP.]

try with thicken, the command extrudes "normal" to the surface, if you cum somewhere you can pull the excess part.

 

[c'erounavolta]

but instead loft the perimeter arches? ?

 

[Cloe85]

I was once Can I know how you did exactly to get to the final result? in one of my attempts I also tried to intersect twice as much as one another but a disaster came out!
I had done so:
-creating arches at the ends
-creation arches with thickness (spline formed by two arches and two lines)-creation of the two lofts representing barrel vaults-intersection of the two lofts (intersection control)
:36_1_4:
gp. I'm trying to retrace all the steps you explained to me to create the surface of the time on a cruise (which then I will try to thicken) exactly with your procedure and not with the others I used, to see if something changes. I broke the two diagonal arches in the center but now I can't join the two diagonal segments. What is the command I have to use? I tried with editpl ---> multiple ---> segment selection ---> join, but it does not work.


Thank you so much to both of you!

 

[GP.]

while being exact from the geometric point of view, the procedure with lofts on the opposite arches is useless for the "construction" material of once, as it creates curved diagonals, not placed on the vertical of the base diagonals (see plant below).
with a trapezoidal plant there is no exact geometric shape, with a regular base the diagonals would be elliptical arches.
with the use of the bow I am convinced that you can well approximate the interpolating curve between the two that delimite the contigue nails.
using a constant thickness the solid at the intradox matches with the guidelines, while at the endradox, fatally, presents some negligible magagna at the crossroads between diagonals and base.

I better describe the procedure I proposed in the post above, with a small variant to not have problems with thickening:

- extension of 50 cm the sides of the trapeze and build the arches at the extremes
- build diagonal arches on the actual basic trapeze
- to combine the two portions of "semidiagonal" uses merge, if it does not work, it checks to have broken properly so that they join in the same point
- construction of the nail with loft between outer arc and spline spring from the above operation
- union of nails to form a single surface
- thickening command applied to the surface, attention to +/- sign of thickness
- draw the solid obtained on the vertical of the four sides of the trapeze

 

[prismacad]

or:
after getting to the point: nail union to form a single surfacemake a copy of the sup. moving it to the z axis of the thickness you want to get

extrude the base of the irregular polygon with a height in addition to that of the two surfaces so that they are completely inside the solid

twice use the pull command with the surface option, first with the upper one then the lower one, so you will get a "clean" solid between the two surfaces.

 

[GP.]

or:
....make a copy of the sup. moving it to the z axis of the thickness you want to get

better a surface offset, to keep the thickness constant.

there is then "the last way", once you create the overlapping surfaces extrude (as surface) the contour and then scolpiscisuperf.

 

[doking]

I was once Can I know how you did exactly to get to the final result? in one of my attempts I also tried to intersect twice as much as one another but a disaster came out!
I had done so:
-creating arches at the ends
View attachment 38689-creation arches with thickness (spline formed by two arches and two lines)View attachment 38690-creation of the two lofts representing barrel vaultsView attachment 38691View attachment 38692-intersection of the two lofts (intersection control)View attachment 38693
:36_1_4:
gp. I'm trying to retrace all the steps you explained to me to create the surface of the time on a cruise (which then I will try to thicken) exactly with your procedure and not with the others I used, to see if something changes. I broke the two diagonal arches in the center but now I can't join the two diagonal segments. What is the command I have to use? I tried with editpl ---> multiple ---> segment selection ---> join, but it does not work.


Thank you so much to both of you!

I instead of the intersection I would have used the command size, cut from the edges of the quadrilateral

 

[c'erounavolta]

It is true that the diagonals are stunned, even so:finger:

 

[c'erounavolta]

you can solve with a nice sliced straight of a choice and take the arches of the atra and make a loft for e.g.View attachment 387

 

[GP.]

I instead of the intersection I would have used the command size, cut from the edges of the quadrilateral

I pulled a corner to show you what happens in the diagonals

you can solve with a nice sliced straight of a choice and take the arches of the atra and make a loft for e.g.

depends on the precision that you can allow the beautiful cloe, the second ones will not have constant thickness, the only way to get it is to thicken on the total surface or an offset of the same.

:smile:

 

[doking]

I pulled a corner to show you what happens in the diagonals
View attachment 38707depends on the precision that you can allow the beautiful cloe, the second ones will not have constant thickness, the only way to get it is to thicken on the total surface or an offset of the same.

:smile:

:finger:....

 

[Cloe85]

Thanks to everyone, I'm trying now to do the steps that suggested me gp.
I put some time on it every time because once I make the model on autocad I have to export it to straus and see if the irregularities do not crash the program when trying to create the mesh of the volume that I built on autocad.... I cross my fingers!

 

[Cloe85]

I believe however that the gp solution is the best, those "salts" on the diagonals of the time straus does not digest them because in the creation of the mesh they fit the points considerably and the program does not hold. Consider that this is one of 7 times of a hall of a medieval castle so the overall model is already heavy of its!

 

[Cloe85]

Nothing to do, I can't join the two segments of spline! I put myself both in the plant and in the prospect and checked, the point seems to be the same for all 4 arches. He also has the same coordinates. . .How is it possible? I miss what I'm wrong

attack also dwg file if it should serve to understand!
View attachment volta gp.dwg

 

[MarcoBi]

creates a bird passing through the three points of the spline. .

 

[Cloe85]

marcobi with "three points of the spline" do you mean the 2 extreme points of the segments that I want to join and the cross point of the diagonals? so I tried but it doesn't work. .

 

[doking]

cloe85 tries to copy everything in a new file, I did so and now the two arches fit perfectly