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Varying cross section along length of span (x) via Programming in MathCAD solution needed !

AL_10888052
10-Marble

Varying cross section along length of span (x) via Programming in MathCAD solution needed !

Version : PTC MathCAD Prime 9.0.0.0

So, I had a problem statement in one of my bridges where I had depth as varying (basically z coordinate value with a certain formula that could be followed).

AL_10888052_0-1702205029584.png

So, here I used a constant formula which could be used for all points of vertex needed in z cordinate which I defined as various variables that it picked automatically. And worked & I could get my function sorted. where I stored my variable values reading from excel which then used this formula for all z coordinates and formed as we move along x axis.
So this basically is the solved one

AL_10888052_1-1702205160842.png


Now, my new problem statement in which I am using my same sheets, is that I have different varying values both in y and z coordinate which will be reading from my excel sheet. But the formula is not same for each point of vertex or cross section i.e., y and z coordinate points (different formula).
The y & z values have to use the formula's as below for each y & z coordinate

AL_10888052_2-1702205517234.png

Now, I have stored these variables i.e., 

AL_10888052_3-1702205571847.png

where, 

AL_10888052_4-1702205601661.png

variable data gets read from same excel. and cbsdata reads 

AL_10888052_5-1702205656941.png

to have 1 cross section value at certain location as master cross section.

Now, the constant formula in z coordinate the first one which is solved was written like this

AL_10888052_6-1702206033177.png

It picks the variable data from excel, is called here and formula made here which uses for each point of z coordinate to form polygon but also, changes variable as we move in the x direction (length).

Also, for constant polygon points, it is used to write in this way in my earlier work

AL_10888052_7-1702206147947.png



Problem is : I am trying to find a way to write my new problem statement in such a way that my variable values (s1, s2, s3, h1, h2 and others) are already stored and called by me in my current mathcad sheet which takes value as we proceed every 2m along x. It should interpolate in between and form the bridge and cross sections.
I want it to make the formula to be taken for each point of z coordinate and y coordinate as screenshot is shown for all the formula's i.e., 
AL_10888052_2-1702205517234.png
This formulation to be made for polygon in there and then it should pick these variable values as we move along xber. And form various cross section and interpolate and form the structure.
Can the community help, I am stuck ?

Attaching below :
Input data sheet : indata
Mathcad sheet that has my problem statement that needs to be resolved : A Förutsättningar
Mathcad sheet that has one problem already solved (same formula for all points of polygon but variables) : A Förutsättningar_solved


The code is written in this

AL_10888052_8-1702206612146.png


And further can be found from page 6,7 in both sheets where concrete cross section is mentioned.

1 ACCEPTED SOLUTION

Accepted Solutions

Hi,

Got all the file from backup.

 

Cheers

Terry

 

View solution in original post

52 REPLIES 52

Hi,

 can you do a quick hand sketch to show how s1, s2, s3, h1 etc make up the section?

 

Cheers

Terry

Hi,

Think this is what you are looking for.  It is x,y coordinates not y,z but that is a simple fix.

Enclosed Prime 9 file

Cheers

Terry

Sure. Here is the section

AL_10888052_0-1702406549591.png


Need help in this.
It takes my variables value calling from excel (stored in some variable). Then takes formula for each point of polygon, for y and z coordinate and makes section at each point of x (from 0m to 160m at 2m interval). 

Hi,

 

There is a problem with the inout data at length  146 m

Capture.JPG

 

 

Capture2.JPG

Capture3.JPG

Capture4.jpg

Unfortunately I was doing two things at once and forgot to save the file on closing.  These pictures are all you get.

 

Cheers

Terry

Hi,

Got all the file from backup.

 

Cheers

Terry

 

Hey, Actually that has worked to call the cross section on the sides along with Ixx, Iyy, Abridge (but it is coming in -ve. Hence, the graph is reverse but that can be sorted).
However, the main problem remains is in this sheet going down, as we have not calculated

AL_10888052_0-1702982230764.png

These factors as variables too. But can you help me regarding the same. As when you go below where we are actually using them. It is still getting called by yc, zc which you have used to get variable sections along (i = 81). But how should we actually make it work
As when  you go to topic A.3.1.2.

AL_10888052_1-1702982336810.png

Since we have yc, zc still cbsdata which you used. It calls one section only further below the sheet.
And in A.3.1.2.4
not getting these values as well as we don't have variable beffective reading from top.


AL_10888052_2-1702982415887.png


& like here if you change xeemple here as well since we have yc zc from cbsdata used so, no matter where I check the cross section it is same which I store in indata excel.

AL_10888052_3-1702982726869.png


& same problem here as c/s is same, so in elevation it shows same width and hence cables that I have read from my indata sheets coming out in zones

AL_10888052_4-1702982815295.png


It was coming upside down, so I changed your matrix (reversed z points basically).

AL_10888052_5-1702982841337.png



I have updated the file abit to resolve few nicks here. Please if you can help sort this out as per how you called the function and will be using the same. So it will be a huge help to sort this one. Sorry for the trouble, but I think we have almost resolved it.
Attaching the latest files.

Thanks for the earlier solution, it was great the approach you adopted. Replying late as I was trying to see how you have worked, why upside down and then found how can it be implemented. Seems like I need your help in getting it applied below in my calculation.
Sorry and thanks again 🙂

Hi,

a lot to unpack here so will do it bit by bit.

1)

Areas and Inertias using the formula used depends on going round clockwise or anti-clockwise.  One of them gives the negative value of the other.

Cannot remember if it is anticlockwise or clockwise that gets the positive value.

 

2)

The input of the following data is not available in the Excel datasheet.

Capture3.JPG

Capture2.JPG

Capture.JPG

Capture4.jpg

Cheers

Terry

We can ignore the 2. Point, got that (will take care of it).
But moving further onto 1. point of negative postive and then beff topic A.3.1.2. and further (as it takes yc and zc itself. Can you help out in further using your initial way of calling all variables and getting area and Inertia. How to then, sort further beff and beneath Mathcad calcs that includes varying cross section inspite of yc and zc. And also, then, getting same in the end that reflects width accordingly that contains my PT cable and can then be seen (in all the screenshots attached) above by me.
Basically to get your concept of multiple cross sections fed into my below calculations that are set as per 1 yc, zc, Moment of inertia and so on i.e., same single cross section. Basically I am dealing changes as per multiple cross sections (varying). You have got it figured and I think will be most helpful to me looking at your way of calling cross sections and A/I properties.

Thanks 🙂
Looking forward to it.

Hi,

It is 3::00 am in the morning here, will look at it again in the morning.

Cheers

Terrt

Oh, thanks 🙂
Sure
GN
Cheers

Hey

I used a negative operator equal to Abridge and Iybridge (getting it in (+ve) axis of y in graph. Also, in indata sheet, if you see, I have changed z coordinates i.e., bottom of slab at 0,0 and then, forming the polygon in upwards direction. Sharing updated files.
Now, the bottom calculation functions needs to be aligned as per the way you have called the variable parameters along i. As I have mentioned above and in mathcad as we move from A.3.1.2 to the end.

Looking forward to some solution. Thanks 🙂
I think on correct path to be resolved.
Thanks again

Hi

Have not changed the excel file.

Have corrected an equation already provided.  No "n" on the end.

Capture.JPG

Capture2.JPG

 

Have shown how to extrapolate at any position along bridge for area, inertia, effective widths, and section.

 

Hope this helps.

Cheers

Terry

Hey

Just checked and extrapolating in this way is working, and I have used this way to call my functions and get the data.
Further, but the main doubt remains is
For example :
In A.3.1.2.4 Effektiv flänsbredd
I'm calculating it by matching the span as I move from point to point which is xber. And for the same, I have used RCassignSpanstoX function which is made in my separate tool file mathcad sheet i.e. (attaching screenshot of that function here),

AL_10888052_0-1703089173533.png

And I'm using this function in my main A sheet like this along with Lo as

AL_10888052_1-1703089226281.png

 

AL_10888052_2-1703089256122.png

It is also not reading xber which is already being called by me at the start input if you can see, where it is reading and showing values quite correctly. 

In the solved mathcad sheet which I attached on Day 1 here, you can see or here attaching a solved SpantoX  calculation and proper graph.
You have calculated beffective, Area, I, etc, as per the drawing I had attached of cross section which is correct as per variables. But how to use it below here is my original question in calculation in these functions to get the calculation working for this variable problem statement.

Here is one solved example :

AL_10888052_3-1703089444279.png

 

AL_10888052_4-1703089455732.png


Used the same toolbox function. 

Sorry for such indepth problem statement. But really appreciate you getting the gist on it. Just that need to get it as per my calculation.

Same way in the further below calculation on this A sheet. 
Also, in A.3.3.2

AL_10888052_5-1703089603055.png

I have used a function which I made in my toolbox named PRCpolygonDrawtendons, which I mentioned yesterday that the elevation depth and plan width is not taking up here as variable and unable to work it out as well to assign as per how you called my variables as per cross section figure and looped in is=1...S1var. But the main thing remains is how to use that here in below calculation and if toolbox funxtion needs to be updated according to how you called the variables to calculate Area,I, cross section properties, etc. Then how to implement that in main calculation in A sheet and if toolbox sheet needs updation too.

Here is PRCpolygonDrawtendons function snip :

AL_10888052_6-1703089874095.png


These couple of things still remains unsolved for me. Else, I have implemented what you mentioned and did the change.
If you can have a look and suggest on it. Would be great.

Thanks for such technical discussion over here. Hope you also having a different problem statement to engage this time. 🙂
Sorry for consuming your time. But it is actually very interesting and a little different with everything fluctuating and no constants to freeze. Hence, I had to come here.

Thanks again 🙂

P.S : Please let me know if you need any else function as well from my toolbox sheet which I created and am using to call in my calculation in main sheet.
However, I think thes functions should be able to resolve atleast my A sheet from top to bottom. Which I have filtered and dusted till A.3.1.2.4. Remains unsolved as to how would you apply and apply your approach here in to get the calculation beneath working from A.3.1.2.4.

Hi

I have been trying to figure out what other possibilities could I use to get the parameters and remaining things as per some condition so I can use them to get the results and in my calculation.
So, Here in my sheet, I have called xber which is by this function 

AL_10888052_0-1703144096347.png


Now, the parameters that you have calculated are as per every 2m data that is provided. And hence, returns 81 values of any parameter I want to make.
And you have linearinterpolated same as I can see

AL_10888052_1-1703144177656.png

Hence, I was thinking that in the meantime, if we can find a way to have all these values relate and return by extrapolate or something as per my xber which if you see in my case has 

AL_10888052_2-1703144271650.png

has 988 values spanning in the range from 0m to 160m.

So basically, if we can modify function in such a way in my calculation that all the values returning A,I,beff,etc, either after coming from 0 to 160m,2m interval: then calculates and polates as per xber distances and returns 988 calculation values of A,I,beff, etc.
Or in the initial go only, rather than interpolating (0,160,2m). Somehow we can modify and write a new function or modify so that we directly start getting the values as per my xber (988 total values) from 0m to 160m interval.

So for example: in my contant already developed calc sheet in other work, I made the function such that I am getting my values like this

AL_10888052_3-1703144562010.png

xber polates (0 to 100m span) and returns 600 values in between interval in increasing order.
And then I get for ex beff:

AL_10888052_4-1703144620579.png

b1eff values spread 600 value numbers spanning from 0m to 100m length.
So, if you can in the meantime, you figure above thing or someone else does. If you have a take on it and how we can modify same in this case in my sheet. 

P.S : 

AL_10888052_0-1703146089791.png

This way I have functioned earlier. Just for reference.
Same problem I asked last night. Just trying to figure out things.

Thanks for your time 🙂

Capture.JPG

Hi
Saw the stack approach option works in both these. Can you also let me know regarding beff as per xber. Which I have explained in detail earlier today just before this solution of yours.
Sorry for taking up your time.
Thanks 🙂

This one

AL_10888052_0-1703153573747.png

 

I have tried this.

AL_10888052_0-1703231831296.png

Sorted l0,x error problem. And getting 1042 values of b1eff, b2eff & b3eff as xber has 1042 values (spanning from 0m to 160m). I have updted my main function RCspanX in my tool calculation sheet. So it got resolved 🙂

Now, 2 concerns are here remaining :
First, my factor of fb is 0.6. However, the b1eff values using above loops even when I have used b1bridge in function below to store b1eff and likewise is returning same 1.027m values in all 1042 values (from 0 to 160m).
However, it should return, varied values like this which I have done on side.

AL_10888052_1-1703232006921.png

Same problem in all b1eff, b2eff, b3eff.
It is getting resolved by is=1..row and storing like above. 
But also, the second problem that binds to it or not able to figure out why this error still pertains is..
Even when I am getting 1042 values matching same index in all y values of graph (b1eff,b2,b3eff) and xber outside this graph also has 1042 values (om to 160m). Still shows xber error in graph. Hence, not getting the graph plotted and hence, the calc work.
Rest all is sorted in this sheet. 🙂
Kind of stuck in this last 2 things related here in this function and graph.

AL_10888052_2-1703232203030.png

Attaching the sheet in which I have done this updated work and all rest things are working fine.

Hi,

Cannot help on this graph as do not have the input data.

Capture.JPG

Capture2.JPG

Capture3.JPG

Capture4.jpg

Hi
Please find this sheet as well containing Egentygnd tab in excel named balksnittkrafter. (om to 160m) results which I extracted from analysis of my structure. And, hence, I want the data further to come aligned as per the data points according to my results, rather than just 2m interval geometry points.
One form of how can I do this, will help.
Thanks 
Please let me know if any further info is needed. Stuck on it. As to how polate it according to the data points of results.

Hi,

Thanks for the worksheets.  Spent some time looking at them.

Bottom of page 5

Top of page 6

At some stage it is necessary to interpolate the results workbook.

This is not possible with nearly equal double entries in the interpolating vector vx in linterp(vx, vy, x).

So a solution that deletes the nearly duplicates is necessary.

Note N, VZ, VY, My, MZ has similar value at duplicate point.

MT or torsion does not but the average is close enough for this action. 

Simple enough to write another function that uses the max not average for MT

Capture8.JPG

Note in image below linterp() fails on the raw data. 

Capture.JPG

If the duplicates are taken out interpolation is possible.  Pass in any results column and get back same without duplicates.

Capture2.JPG

Top of page 7 x.extra is defined with dx = 205 mm for one set of xber

Capture3.JPG

Bottom of page 12 it is done again with dx of 200 mm

Capture4.jpg

 

What I am suggesting is two independent interpolation schemes.

linterp(vx, vy, x)

 

LM.var as vx for concrete section information including b.eff

Reduced  x.analys as vx for results

This means you can have at 81.2 m say

Capture9.JPG

and

Capture10.JPG

Bottom of page 29, Top of page 30

With two independent interpolation schemes b.eff only needs to match LM.var x values at each concrete section.

for each LM.var find the effective length at that point and store in variable lj.

Now is easy to find beff at each LM.var.  beff can be combined with section information at each LM.var.

Capture5.JPG

Capture6.JPG

Capture7.JPG

 

Effective section properties are easily determined at each LM.var.

Is the reduced flange area only applicable in compression with full flange for tension?

 

Cheers

Terry

 

Hi,

Have found an error in the worksheet on calculation of beff

Needed to add an indices of i to all instances of b

Capture.JPG

Capture2.JPG

Capture3.JPG

Hi
Thanks for the reply. Actually my question is that I do not want values according to Lmvar (as they return 81 datas, for every 2m). I want the result to be according to the xber, lo. So, I have calculated lo,x using this

AL_10888052_0-1704183963248.png


It returns lo,x as per xber and hence, you can see lo values spread across xber and hence, 

AL_10888052_1-1704184053295.png


882 data of l0 in increasing order from 0m to 160m.

The problem with having beff values as per Lmvar is that in my output excel, I am using this

AL_10888052_2-1704184142138.png

And it shows error because I have b1,b2,b2,beff as per Lmvar (81 values). However, I have x and lo as per xber i.e., (882 data).

And I need b1,b2,b3,beff1,beff2,beff3 as per xber only, Because my xber is generated using my analysis result that takes x as per mesh order from 0m to 160m. Xber having 882 values from 0m to 160m in increasing order.

AL_10888052_3-1704184513301.png

 


Hence, for further calculation, I have to generate and make every calculation as per xber.

Hope I am able to explain my query simplified. Please let me know if you need any further information or anything from my end.

Attaching updated sheet here.. balksnittkrafter sheet reading result is already attached by me above.

P.s : Solved constant cross section output result of beff comes like this. For reference.

AL_10888052_4-1704184703247.png

AL_10888052_5-1704184716772.png

This bridge was of 100m and had 600 data points as per xber. So, that's how I calculated beff's and b's as per xber. So as to return corresponding to xber m.

Also, lo is already done by me in the below attached sheet.

AL_10888052_6-1704184803036.png

And you can see 882 lo's as per xber.

I used RCassignspanstox function which is made like this in separate sheet.

AL_10888052_7-1704184875867.png

For B's and beff's, I have not used it in constant cross section, it just directs as per xber using function. But you can see if needed for reference. For lo, I used this.


Also, in the end of this sheet below this graph for PT cables. I am getting properties.

AL_10888052_3-1704185897832.png

 

But facing same kind of problem.

Solved example shows

AL_10888052_2-1704185876920.png


Getting result in this as well, as per xber since data points match.

But if you can look at this problem Pm0 and sort this one. I think it is based on similar grounds of beff and hence stuck. Please if you can look. Because as of now, I am not getting my output excel generated with beff sheet and this Pm0 sheet calculation and the problem which I feel is less datasets and I cannot resolve it using lvar. As I need as per xber only i.e., (882 data points). Since, my analysis results are as per 0m,0.2,0.35,0.42m, etc. accordingly.

So please if you can look into beff and Pm0 so it will be fully resolved with the purpose how I want. To match my calculation points.


Thanks

Btw, Happy New Year Terry 🙂
Cheers

And No, the reduced flange area is not only applicable in compression but later controlling flange contribution using my input from excel for tension. So, as per percent, it calculates b's and beff's and takes into consideration later in calculation for compression and tension.

Hi,

First answer so far. for beff aligned with xber

Top of page 26 in the right hand side..

Just interpolate between the values established for points where section information is given.

Capture.JPG

Produces the same graph but with 882 points

Capture2.JPG

Got to do something else before looking further

Cheers Terry

Happy New Year,

Could you send the spreadsheet as well Thanks

Hi
Yes sure, And effective flange width sheet is getting made now. As we have interpolated as per xber. Thanks.
Please find attached below spreadsheets that concern calculations for it. Please let me know if anything else is needed. Pm0 basically is the PT force as per xber for each cable as per where it starts and ends. Hence, the graph shows like this

AL_10888052_0-1704259610913.png

It reads PT cable data and makes profile from indata including PT force values and everything. And then, should in the same way like beff, return it as per the xber throughout. Simply what I am getting in the above graph. To be returned in output excel according to xber and each cable.

Output sheet is working for beff now. And returning me fine values.
PFA updated Mathcad sheet as well.

I hope I have not bored you or strolled too much with interlinked tasks. Hope you also finding this work reasonable and decent. I have heavily interlinked things. But did everything for a straight or curved geometry (bridge) but constant cross section.

Now, for the varying one, I need a knowledgeable fresh mind of Mathcad to resolve and sort abit of my way already prepped sheets. And I find someone like you or I would say you, are coming of a great help and guidance to it. It is working out. I might need your help in further calculations as well. I have spread my calculation work into A,B1,B2,B3,,C1.. etc.. sheets which are linked but inorder, hence resolving A first courtesy of your precious time and help. 

Thanks again 🙂

Hey
Did you arrive at any solution? Any progress made!

Hi,

Been working on something else will get some time tonight to look at the prestressing tendons.

Cheers

Terry

Sure. Thankyou.
Looking forward to it.

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