<
From version < 235.1 >
edited by Fredrik Lagerström
on 2020/03/30 13:20
To version < 236.1 >
edited by Fredrik Lagerström
on 2020/03/30 13:20
>
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... ... @@ -378,9 +378,11 @@
378 378  
379 379  The [[image:1585547429886-498.png]] //Plate// module calculates internal forces in the [[(% class="wikiinternallink" %)**plate**>>doc:Manuals.User Manual.Structure definition.Plate (Geometry).WebHome]](%%) regions and in the (% class="wikiinternallink" %)**Global coordinate system**(%%):
380 380  
381 -| |//Mx’/ My’//|bending moment around the **global** **Y / X axis**;
381 +| |//Mx’//|bending moment around the **global** **Y axis**;
382 +| |//My’//|bending moment around the **global** **X axis**;
382 382  | |//Mx’y’//|torsion moment;
383 -| |//Tx’ / Ty’//|shear force for the global X / Y normal and in the Z direction;
384 +| |//Tx’//|shear force for the global X normal and in the Z direction;
385 +| |//Ty’//|shear force for the global Y normal and in the Z direction;
384 384  | |//M1, M2//|principal moments;
385 385  | |//M1/M2//|principal moment directions.
386 386  
... ... @@ -389,7 +389,8 @@
389 389  
390 390  The [[image:1585547536999-311.png]] //Wall// module calculates internal forces in the [[(% class="wikiinternallink" %)**wall**>>doc:Manuals.User Manual.Structure definition.Wall (Geometry).WebHome]](%%) regions and in the (% class="wikiinternallink" %)**Global coordinate system**(%%):
391 391  
392 -| |//Nx’ /// //Ny’//|normal force in the global X / Y direction;
394 +| |//Nx’//|normal force in the global X direction;
395 +| |//Ny’//|normal force in the global Y direction;
393 393  | |//Nx’y’//|shear force in the global X-Y plane;
394 394  | |//N1, N2//|principal normal forces;
395 395  | |//M1/M2//|principal normal directions.
... ... @@ -398,24 +398,19 @@
398 398  
399 399  The [[image:1585547574297-800.png]] //3D Structure// module calculates internal forces and moments in the planar object regions (plate and wall) in their local coordinate system:
400 400  
401 -//M**x’** /// //M**y’**//              - bending moment around the **local y’ / x’ axis** of the region element;
404 +| |//Mx’//|bending moment around the **local y’ axis** of the region element
405 +| |//My’//|bending moment around the **local x’ axis** of the region element
406 +| |//Mx’y’//|torsion moment
407 +| |//Nx’//|normal force in the local x’ axis of the region element
408 +| |//Ny’//|normal force in the local y’ axis of the region element
409 +| |//Nx’y’//|membrane shear force
410 +| |//Vx’//|shear force for the local x’ normal and in z’ direction
411 +| |//Vy’//|shear force for the local y’ normal and in z’ direction
412 +| |//M1, M2//|principal moments
413 +| |//M1/M2//|principal normal directions
414 +| |//N1, N2//|principal normal force
415 +| |//N1/N2//|principal normal directions
402 402  
403 -//Mx’y’//                       - torsion moment;
404 -
405 -//Nx’// / //Ny’//               - normal force in the local x’ / y’ axis of the region element;
406 -
407 -//Nx’y’//                       - membrane shear force;
408 -
409 -//Vx’// / //Vy’//                - shear force for the local x’ / y’ normal and in z’ direction;
410 -
411 -//M1 / M2//                - principal moments;
412 -
413 -//M1/M2                    //- principal moment directions;
414 -
415 -//N1 /// //N2//                  - principal normal force;
416 -
417 -//N1/N2//                     - principal normal directions.
418 -
419 419  == Bar Stresses ==
420 420  
421 421  FEM-Design calculates the normal stress in bar elements (beams, columns and/or truss members) with the following meaning:
... ... @@ -424,51 +424,51 @@
424 424  
425 425  //Sigma x’(min)//        - minimal normal stress (compression).
426 426  
427 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]] **The [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png||alt="icon_PLATEMODULE"]] //Plate// module calculates stresses only in beams. Columns are point supports.
425 +|(% style="width:119px" %)[[image:warning.png]]|(% style="width:1371px" %)The [[image:1585560780742-260.png]] //Plate// module calculates stresses only in beams. Columns are point supports.
428 428  
429 -In [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image008.png||alt="icon_PREDESIGNMODULE"]] //PreDesign//, although the 3D model contains all types of elements, stresses are calculated in columns.
430 -
431 431  == Shell Stresses ==
432 432  
433 -The program calculates stresses in the top, bottom and middle (so called “membrane”) planes of the planar elements. The meaning of top and bottom side depends on the position ([[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png||alt="icon_PLATEMODULE"]] //Plate// module) or the (% class="wikiinternallink" %)**local coordinate system**(%%) (3D modules) of a region element.
429 +The program calculates stresses in the top, bottom and middle (so called “membrane”) planes of the planar elements. The meaning of top and bottom side depends on the position ([[image:1585560836929-262.png]] //Plate// module) or the (% class="wikiinternallink" %)**local coordinate system**(%%) (3D modules) of a region element.
434 434  
435 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image033.png||alt="anal_membrane.png"]]
431 +[[image:1585560829628-689.png]]
436 436  
437 437  Figure: The meaning of planes depending on region position
438 438  
439 439  So, depending on the current FEM-Design module, we get results from the following:
440 440  
441 -//Sigma x’, top /// //membrane /// //bottom//                      - normal stress from //Nx’// in top/membrane/bottom plane;
437 +| |//Sigma x’, top//|normal stress from //Nx’// in top plane
438 +| |//Sigma x’, membrane//|normal stress from //Nx’// in membrane plane
439 +| |//Sigma x’, bottom//|normal stress from //Nx’// in bottom plane
440 +| |//Sigma y’, top//|normal stress from //Ny’// in top plane
441 +| |//Sigma y’, membrane//|normal stress from //Ny’// in membrane plane
442 +| |//Sigma y’, bottom//|normal stress from //Ny’// in bottom plane
443 +| |//Tau x’y’, top//|shear stress from //Nx’y’// in top plane
444 +| |//Tau x’y’, membrane//|shear stress from //Nx’y’// in membrane plane
445 +| |//Tau x’y’, bottom//|shear stress from //Nx’y’// in bottom plane
446 +| |//Tau x’z’//|shear stress (x’ normal and z’ direction)
447 +| |//Tau y’z’//|shear stress (y’ normal and z’ direction)
448 +| |//Sigma vm, top//|von Mises stress in top plane
449 +| |//Sigma vm, membrane//|von Mises stress in membrane plane
450 +| |//Sigma vm, bottom//|von Mises stress in bottom plane
451 +| |//Sigma 1/Sigma 2, top//|principal stresses and directions in top plane
452 +| |//Sigma 1/Sigma 2, membrane//|principal stresses and directions in membrane plane
453 +| |//Sigma 1/Sigma 2, bottom//|principal stresses and directions in bottom plane
442 442  
443 -//Sigma y’, top /// //membrane /// //bottom//                      - normal stress from //Ny’// in top/membrane/bottom plane;
455 +|[[image:warning.png]]|(((
456 +The x’, y’ and z’ directions are valid in the global coordinate system at [[image:1585561722864-126.png]] //Plate// and in the local coordinate system of planar elements in the 3D modules.
444 444  
445 -//Tau x’y’, top /// //membrane /// //bottom                      //- shear stress from //Nx’y’// in top/membrane/bottom plane;
458 +In [[image:1585561745228-967.png]] //Wall// and [[image:1585561749828-130.png]] //Plane Strain//, stresses are calculated only in the membrane plane.
459 +)))
446 446  
447 -//Tau x’z’                                                                       - //shear stress (x’ normal and z’ direction);
448 -
449 -//Tau y’z’                                                                       - //shear stress (y’ normal and z’ direction);
450 -
451 -//Sigma vm, top /// //membrane /// //bottom//                   - von Mises stress in top/membrane/bottom plane;
452 -
453 -//Sigma 1/Sigma 2, top /// //membrane /// //bottom       //- principal stresses and directions in top/membrane/ bottom plane.
454 -
455 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]] **The x’, y’ and z’ directions are valid in the global coordinate system at [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png||alt="icon_PLATEMODULE"]] //Plate// and in the local coordinate system of planar elements in the 3D modules.
456 -
457 -In [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image008.png||alt="icon_PREDESIGNMODULE"]] //PreDesign//, although the 3D model contains all types of elements, stresses are calculated in walls.
458 -
459 -In [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image004.png||alt="icon_WALLMODULE"]] //Wall// and [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image005.png||alt="icon_PLANESTRAIN"]] //Plane Strain//, stresses are calculated only in the membrane plane.
460 -
461 461  == Equilibrium Check ==
462 462  
463 463  The program automatically checks the equilibrium of the analysis calculations. Statical equation is written to the origin [0; 0; 0] of the (% class="wikiinternallink" %)**Global Coordinate System**(%%). It compares the sum of the reactions and the sum of applied loads. Equilibriums can be asked by load case and load combination.
464 464  
465 -Just click the [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image002.png||alt="icon_equilibriumcheck.png"]] //Equilibrium// icon (in Analysis or (% class="wikiinternallink" %)**Design**(%%) mode), choose a load case or load combination to see the equilibrium check results.
465 +Just click the [[image:1585561825859-570.png]] //Equilibrium// icon (in Analysis or (% class="wikiinternallink" %)**Design**(%%) mode), choose a load case or load combination to see the equilibrium check results.
466 466  
467 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png]]
467 +[[image:1585561847367-574.png]]
468 468  
469 469  
470 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image004.png]] [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image005.png]]
471 -
472 472  Figure: Equilibrium check of Analysis calculations
473 473  
474 474  If equilibrium error derives from an analysis calculation, the error will be appeared in percentage in the Error column by equation types (force (F) and moment (M)) and directions (x, y and z directions of the global coordinate system). “Error” shows the differences between the resultants of the queried loads and the calculated reactions.
... ... @@ -485,11 +485,11 @@
485 485  
486 486  Displacement:
487 487  
488 -//ez’(+)//                  - maximal uplift in global z’ direction in [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image006.png||alt="icon_PLATEMODULE"]] //Plate//,
486 +//ez’(+)//                  - maximal uplift in global z’ direction in [[image:1585565432608-409.png]] //Plate//,
489 489  
490 490  // //- maximum motion in the positive direction of element’s local system in 3D modules;
491 491  
492 -//ez’(-)//                   - maximal depression in global z’ direction in [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image006.png||alt="icon_PLATEMODULE"]] //Plate//,
490 +//ez’(-)//                   - maximal depression in global z’ direction in [[image:1585565440941-678.png]] //Plate//,
493 493  
494 494  // //- maximum motion in the negative direction of element’s local system in 3D modules;
495 495  
... ... @@ -502,15 +502,15 @@
502 502  
503 503  The next figure shows the meaning of simultaneous results.
504 504  
505 - Maximal Mx’                                                                  Nx’ belongs to maximal Mx’
503 +[[image:1585565787021-414.png]]
506 506  
505 + Maximal Mx’                                                                  Nx’ belongs to maximal Mx’
507 507  
508 -
509 509  Figure: The meaning of simultaneous results belong to a maximal value
510 510  
511 -Combination of //Load cases// that gives the maximum analysis results in //Maximum of load groups// can be listed in tables. Just use the [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image009.png||alt="icon_list"]] //List// command (//Tools// menu) for the //Maximum of load groups// result data.
509 +Combination of //Load cases// that gives the maximum analysis results in //Maximum of load groups// can be listed in tables. Just use the [[image:1585565803591-518.png]] //List// command (//Tools// menu) for the //Maximum of load groups// result data.
512 512  
513 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.png||alt="figure_118_loadgroups"]]
511 +[[image:1585565809559-156.png]]
514 514  
515 515  Figure: Combination of load cases for maximum of load groups results
516 516  
... ... @@ -520,11 +520,11 @@
520 520  
521 521  This new result type is based on the displacement of the bars and the deflection limitation settings which can be defined by the so-called //deflection lengths//.
522 522  
523 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image011.png]]
521 +[[image:1585565900021-270.png]]
524 524  
525 -In the [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image012.png]] //Deflection// co//nfiguration// dialog, we can specify the types of load combinations/groups for which the deflection check is performed.
523 +In the [[image:1585565905964-204.png]] //Deflection// co//nfiguration// dialog, we can specify the types of load combinations/groups for which the deflection check is performed.
526 526  
527 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image013.png]]
525 +[[image:1585565926731-870.png]]
528 528  
529 529  
530 530  //Deflection lengths// are used to define those bar segments, where the deflection checking criteria/limitations are coincide. The “Simply supported” deflection lines are denoted with blue arcs below the bar, the ”Cantilever and column” types are orange and the “not relevant” types are black. Relative and/or absolute limit can be set for each //length// individually. If both are requested the dominant one will be calculated and displayed.
... ... @@ -533,25 +533,21 @@
533 533  
534 534  For the better understanding of the next two options, namely the //Simply supported// and //Cantilever// mode let us consider the following example, a cantilever frame structure.
535 535  
536 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image014.png]]
534 +[[image:1585565936623-364.png]]
537 537  
538 538  In the midspan we should use the Simply supported option, where we eliminate the rigid body motions in such a way that we connect the endpoints of the length, and measure the deflections of the middle sections from this imaginary line (red skew line on the picture above).
539 539  
540 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image015.wmz||alt="MCj02990090000%5b1%5d"]]|As a consequence of this method, the deflections of the endpoints are zero, the dominant section is usually at the middle of the length.
538 +|[[image:light.png]]|As a consequence of this method, the deflections of the endpoints are zero, the dominant section is usually at the middle of the length.
541 541  
542 542  On the cantilever, we would like to use the cantilever mode, where the dominant value of deflection on this length will be the difference between the maximum and minimum absolute deflection (in this example the largest distance from the red horizontal line). For columns the same calculation method is used, the only difference is that the deflection is measured in the horizontal plane (from the green lines).
543 543  
544 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image016.wmz||alt="MCj04113200000%5b1%5d"]]|For columns only this (//“Cantilever and column”//) option is available.|
542 +|(% style="width:120px" %)[[image:warning.png]]|(% style="width:1322px" %)For columns only this (//“Cantilever and column”//) option is available.|
545 545  
546 -|(((
547 -**Deflection lengths**
548 -)))
549 549  
550 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image020.png]]
551 551  
546 +[[image:1585566012700-385.png]]
552 552  
553 553  
554 -
555 555  As deflection lengths correspond to only specific bar segments, they are independent on the bars in such a way that they can be longer or shorter than the bar itself. But why is this differentiation so important? The answer can be demonstrated with the following two examples. On the left of the picture below, only one beam is drawn, thus if the Relative limit would be calculated directly from the length of this beam, the results would be misleading.
556 556  
557 557  In other words, in the //L/?// formula, instead of the length of the midspan or the cantilever, the whole length of the beam would be substituted. Therefore, we need two Deflection lengths to differentiate the //L// in the Relative limit formulae on the midspan and on the cantilever. In addition, the limit value also can differ for the two types of structure according to the National Annexes.
... ... @@ -558,29 +558,30 @@
558 558  
559 559  In the second case (to the right on picture below) imagine that our aim is to design a beam splice and check deflections. Two beams need to be drawn for the steel design, but of course during the deflection check we want to use the summed length of the two beams for the calculation of the relative limit value. For this purpose, we define one Deflection length over the two bars - this way we make correct calculations in both cases without any additional modification on the structure.
560 560  
561 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image021.png]]
555 +[[image:1585566045189-967.png]]
562 562  
563 563  It is worth to note that in the second case we had two beams, but in contrary to the buckling lengths, definition and editing of deflection lengths can be performed on such set of beams, which are both parallel and continuous.
564 564  
565 565  By default, deflection lengths are generated automatically. This procedure first search all the previously mentioned parallel and continuous beams sets, then intersect them with the edges/axes of the structural elements (beams, columns, trusses, plates, walls, line and surface supports) and point supports. In the majority of the cases deflection lengths obtained by this way are reasonable from engineering point of view, but in some cases we may want to modify them. A good example can be a structure consisting of two beams with a horizontal support, which should not be considered in the deflection checking process. The following flow diagram illustrates the modification of the two beams step by step. By default, as we can see in the upper picture, the automatically generated deflection lengths coincide with the beams because they are intersected with the horizontal point support. If we would like to have one deflection length over the two beams, we can draw it between the support groups using the Define tool, similarly to the buckling lengths. By this way, the new length substitutes the original ones!
566 566  
567 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image022.png]]
561 +[[image:1585566057730-325.png]]
568 568  
569 569  
570 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image016.wmz||alt="MCj04113200000%5b1%5d"]]|Deflection length has its own layer.|
564 +|(% style="width:107px" %)[[image:warning.png]]|(% style="width:1308px" %)Deflection length has its own layer.|
571 571  
572 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image023.png]]
566 +[[image:1585566078715-848.png]]
573 573  
574 574  //Deflection check// button becomes active if Load combinations and/or Load groups are already calculated. The utilization results can be displayed from the //New result// dialog.
575 575  
576 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image016.wmz||alt="MCj04113200000%5b1%5d"]]|The Deflection checking process considers only the straight beams and columns. For beams the deflection is measured along their own local z’ axis, for columns it is measured in the global horizontal x-y plane.
570 +|[[image:warning.png]]|The Deflection checking process considers only the straight beams and columns. For beams the deflection is measured along their own local z’ axis, for columns it is measured in the global horizontal x-y plane.
577 577  
578 578  Results requested for a //Load combination// can be displayed both on the deformed and undeformed shape.
579 579  
574 +[[image:1585566093043-275.png]]
580 580  
581 581  Due to the fact that the limit values of the calculation are controlled by the Deflection lengths, the result is constant along them. In other words we have one (dominant) utilization value for each Deflection length. Results for //Maximum of load combinations //and //Maximum of load groups //are only displayed on the undeformed shape of the structure.
582 582  
583 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image026.png]]
578 +[[image:1585566101399-508.png]]
584 584  
585 585  = Imperfections =
586 586  
... ... @@ -587,36 +587,22 @@
587 587  Imperfection calculation is run only for steel bar elements of the structure. Users can add imperfections to a structure in two ways:
588 588  
589 589  * **Imperfection modeled by defining loads (manual)**
590 -
591 591  Place for example horizontal point and line loads on a multi-storey building to model imperfection manually.
592 -
593 593  * **Imperfection calculation according to the formula EC3: 1-1 (automatic)**
594 -
595 595  For load combinations, the program can calculates the probable imperfect shapes in real dimensions from the mode shapes (get from (% class="wikiinternallink" %)**stability analysis**(%%)) according to Eurocode. (% class="wikiinternallink" %)**Second order analysis**(%%) must be run by using imperfection. To do automatic imperfection calculations, activate //Imperfections// and set the required number of the imperfect shapes (//Rqd.// cell) for the load combination which you would like to run imperfection for.
596 -
597 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image027.png||alt="anal_imp1.png"]]
598 -
588 +[[image:1585566123852-913.png]]
599 599  Figure: Imperfection calculation by load combination
600 -
601 -For the automatic imperfection calculation you got the buckling shape of the structure with real size in real dimension. Critical parameter assigned to a buckling shape is also available with the following meaning:
602 -
603 -//critical parameter = critical buckling force/actual load//
604 -
605 -or in other words:
606 -
590 +\\For the automatic imperfection calculation you got the buckling shape of the structure with real size in real dimension. Critical parameter assigned to a buckling shape is also available with the following meaning:
591 +\\ //critical parameter = critical buckling force/actual load//
592 +\\or in other words:
607 607  if the critical parameter is bigger than 1, the structure or a part of it is sufficient to perform the stability analysis; if it is smaller it is not.
608 -
609 609  If the critical parameters differ a lot between the buckling lengths, the first buckling shape is the critical. If the critical parameter values are close to each other, it is your decision what structural part you check by its shape.
610 -
611 - The factor defines the real imperfect shape, so:
612 -
613 -//imperfect shape in real dimension = factor * buckling shape//
614 -
615 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image028.png||alt="anal_imp2.png"]]
616 -
595 +\\The factor defines the real imperfect shape, so:
596 +\\\\ //imperfect shape in real dimension = factor * buckling shape//
597 +\\[[image:1585566211268-838.png]]
617 617  Figure: Automatic imperfect shape calculation
618 618  
619 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image015.wmz||alt="MCj02990090000%5b1%5d"]] **Before imperfection calculation, it is recommended to set minimum 4-5 **//division numbers//** (finite elements) for bars.
600 +|[[image:light.png]]|Before imperfection calculation, it is recommended to set minimum 4-5 **//division numbers//** (finite elements) for bars.
620 620  
621 621  = Stability Analysis =
622 622  
... ... @@ -626,7 +626,7 @@
626 626  
627 627  If the //Rqd. as positive// is checked, program will calculate as many stability shapes as necessary to get required number of shapes with positive critical factor. Since it is an iterative method, maximum number of iteration steps can be set by the User in Max no. of iteration cell.
628 628  
629 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image002.png]]
610 +[[image:1585566484604-695.png]]
630 630  
631 631  Figure: Stability analysis by load combination
632 632  
... ... @@ -634,6 +634,7 @@
634 634  
635 635  Critical parameter assigned to a buckling shape is also available with the following meaning:
636 636  
618 +(% style="text-align: center;" %)
637 637  //critical parameter = critical buckling force/actual load//
638 638  
639 639  or in other words:
... ... @@ -640,35 +640,20 @@
640 640  
641 641  if the critical parameter is bigger than 1, the structure or a part of it is sufficient to perform the stability analysis; if it is smaller it is not.
642 642  
643 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png]]
625 +[[image:1585566527455-423.png]]
644 644  
645 645  Figure: Buckling shape calculation
646 646  
647 647  The last three columns shows the probability of the buckling shapes are global or local, where //eH //meant for horizontal displacement, //eV// for vertical displacement (global Z direction) and //rZ// for rotaion around global Z axis.
648 648  
649 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image004.png||alt="egerpad%20copy"]]
650 -
651 -|(((
652 -1st shape
653 -
654 -__Global__ in horizontal direction
631 +|(% style="width:66px" %)[[image:1585566587364-622.png]]|(% style="width:1424px" %)(((
632 +In the example below, the //eH// value of the first shape is 89%, which means it is probably a global buckling shape with horizontal displacement.
655 655  )))
656 656  
657 -|(((
658 -3rd shape
659 659  
660 -__Global__ in rotational direction
661 -)))
636 +(% style="text-align:center" %)
637 +[[image:1585566779077-490.png]]
662 662  
663 -|(((
664 -4th shape
665 -
666 -__Local__ in rotational direction
667 -)))
668 -
669 - In the example below, the //eH// value of the first shape is 89%, which means it is probably a global buckling shape with horizontal displacement.[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image009.png]]
670 -
671 -
672 672  Displaying the result (see the leftmost inset above) and examining the buckling shape shows that this is indeed a case of global buckling with the horizontal displacement of the frame’s top.
673 673  
674 674  The same structure’s second shape possesses a very high //rZ// value (99%), meaning this almost certainly is a global torsional buckling shape (shown in the middle inset).
... ... @@ -676,10 +676,11 @@
676 676  The fourth shape’s //eH, eV //and// rZ// values are significantly lower, which implies it is a local buckling shape. As the rightmost inset shows, the assumption was correct (local buckling of both columns).
677 677  
678 678  
679 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]]|Higher probability values shows high probability that the shape is global. If there are not enough shapes calculated, none might be global.|
646 +|[[image:warning.png]]|Higher probability values shows high probability that the shape is global. If there are not enough shapes calculated, none might be global.
680 680  
681 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image011.wmz||alt="MCj02990090000%5b1%5d"]] **Before stability analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
682 682  
649 +|[[image:light.png]]|Before stability analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
650 +
683 683  = Eigenfrequencies =
684 684  
685 685  == Mass/Vibration shape ==
... ... @@ -692,59 +692,66 @@
692 692  * The 90% total effective mass is reached in horizontal direction
693 693  * The maximum iteration number is reached
694 694  
695 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image012.png]]
663 +(% style="text-align:center" %)
664 +[[image:1585566873054-101.png]]
696 696  
666 +(% style="text-align: center;" %)
697 697  Figure: Dynamic calculation
698 698  
699 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]] **Dynamic calculation requires (% class="wikiinternallink" %)**masses**(%%) to be predefined.
669 +|(% style="width:119px" %)[[image:warning.png]]|(% style="width:1371px" %)(((
670 +Dynamic calculation requires (% class="wikiinternallink" %)**masses**(%%) to be predefined.
700 700  
701 -[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)**Seismic analysis**>>path:#_Seismic_Analysis]](%%) needs the eigenfrequencies calculations.
672 +(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)**Seismic analysis**(%%) needs the eigenfrequencies calculations.
673 +)))
702 702  
703 703  In Calculation / Eigenfrequencies dialog the user can set the level of top of the substructure. The masses will be neglected __at__ and __under__ this level.
704 704  
677 +[[image:1585566963747-898.png]]
705 705  
679 +[[image:1585566974017-250.png]]
706 706  
707 707  
708 708  In the mass centre of the masses the total mass is displayed with red circle.
709 709  
710 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image011.wmz||alt="MCj02990090000%5b1%5d"]] To get the whole structure’s mass centre position set the level of the Top of the substructure a bit under the structure.
684 +|(% style="width:111px" %)[[image:light.png]]|(% style="width:1379px" %)To get the whole structure’s mass centre position set the level of the Top of the substructure a bit under the structure.
711 711  
712 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image011.wmz||alt="MCj02990090000%5b1%5d"]] This function is useful to neglect the foundation mass in the eigenfrequency calculation so the total mass contribution in Modal analysis can reach >=90%.
713 713  
687 +|[[image:light.png]]|(((
688 +This function is useful to neglect the foundation mass in the eigenfrequency calculation so the total mass contribution in Modal analysis can reach >=90%.
689 +
714 714  Results of Eigienfrequencies calculation:
715 715  
716 716  //Masses//                   - mass matrix of (% class="wikiinternallink" %)**point masses**(%%) and/or (% class="wikiinternallink" %)**masses calculated from load cases**(%%) converted into finite element nodes;
717 717  
718 -//Vibration shape//   - vibration shape and associated eigeinfrequency (//Frequency//) and periodic time (//Period//).
694 +//Vibration shape//  - vibration shape and associated eigeinfrequency (//Frequency//) and periodic time (//Period//).
695 +)))
719 719  
720 720  
721 -Figure: Results of dynamic calculations
698 +|(% style="width:109px" %)[[image:light.png]]|(% style="width:1381px" %)(((
699 +Before dynamic analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
700 +)))
722 722  
723 -**[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image011.wmz||alt="MCj02990090000%5b1%5d"]] **Before dynamic analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
724 724  
725 725  == Shear center result ==
726 726  
727 727  FEM-Design can calculate //Shear centers// for each storey of a building. The figures below show a shear center result of an Eigenfrequency calculation.
728 728  
729 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]]|For displaying shear center, diaphragms are needed for every storey.
707 +|[[image:warning.png]]|(((
708 +For displaying shear center, diaphragms are needed for every storey.
730 730  
731 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image021.png]] [[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image022.png]]
710 +[[image:1585567150564-165.png]][[image:1585567157139-355.png]]
711 +)))
732 732  
733 -|[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image010.wmz||alt="MCj04113200000%5b1%5d"]]|Each displayed shear center represents the result of a calculation based on the storeys below that storey. For example, the calculation of the center displayed on “Storey 2” takes also “Storey 1” and “Foundation” into account.
734 734  
735 -|(((
736 -Values in the Tooltip:
714 +|[[image:warning.png]]|Each displayed shear center represents the result of a calculation based on the storeys below that storey. For example, the calculation of the center displayed on “Storey 2” takes also “Storey 1” and “Foundation” into account.
737 737  
738 -* __alpha__: the angle between the X axis of the global coordinate system and stiffness directions,
739 -* __EI1, EI2__: stiffnesses in principal directions of strains,
740 -* __x, y, z__: the global coordinates of the shear center.
741 -)))
716 +[[image:1585567210762-613.png]]
742 742  
743 743  Shear center results can be listed in //List tables dialog/Analysis/Eigenfrequencies/Shear center.//
744 744  
745 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image025.png]]
720 +[[image:1585567229877-565.png]]
746 746  
747 -[[image:file:///C:/Users/Fredrik/AppData/Local/Temp/msohtmlclip1/01/clip_image026.png]]
722 +[[image:1585567234356-994.png]]
748 748  
749 749  = Seismic Analysis =
750 750  
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