<
From version < 236.2 >
edited by Fredrik Lagerström
on 2020/03/30 13:21
To version < 236.3 >
edited by Fredrik Lagerström
on 2020/04/01 14:32
>
Change comment: There is no comment for this version

Summary

Details

Page properties
Content
... ... @@ -28,7 +28,7 @@
28 28  
29 29  Analysis settings contain general and calculation-dependent settings. This chapter summarizes these settings and their effect on the result. Clicking //OK// runs Analysis according to the settings and selected calculation types. Other chapters introduce the display of results and their documentation (such as listing results in tables).
30 30  
31 -= General Analysis Settings =
31 += {{id name="General Analysis Settings"/}}General Analysis Settings =
32 32  
33 33  == Finite Element Types ==
34 34  
... ... @@ -132,7 +132,7 @@
132 132  
133 133  [[image:1585304848899-842.png]]
134 134  
135 -= Analysis for Construction stages =
135 += {{id name="Analysis for Construction stages"/}}Analysis for Construction stages =
136 136  
137 137  User can start the construction stage calculation at Analysis/Calculation/Construction stages. There is two calculation method, so called //Incremental “Tracking” method// and //“Ghost” structure method.//
138 138  
... ... @@ -149,7 +149,7 @@
149 149  [[image:1585304895405-781.png]]
150 150  
151 151  
152 -= Analysis for Load Cases and Combinations =
152 += {{id name="Analysis for Load Cases and Combinations"/}}Analysis for Load Cases and Combinations =
153 153  
154 154  Analysis calculations can be done by load case and/or load combination. The next table summarizes the results available for load cases and load combinations by FEM-Design modules.
155 155  
... ... @@ -257,8 +257,6 @@
257 257  
258 258  == Connection Forces ==
259 259  
260 -(% style="color:#c0392b; font-size:36px" %)**-=-=-=-=-=-=-=-=-=-=- CONTINUE WORK HERE -=-=-=-=-=-=-=-=-=-=-**
261 -
262 262  Similarly to reactions, the program calculates the forces and/or moments in the connection objects ((% class="wikiinternallink" %)**Edge connection**(%%), (% class="wikiinternallink" %)**Point-point connection**(%%) and/or (% class="wikiinternallink" %)**Line-line connection**(%%)) by direction component and their resultants.
263 263  
264 264  The available result components:
... ... @@ -386,7 +386,6 @@
386 386  | |//M1, M2//|principal moments;
387 387  | |//M1/M2//|principal moment directions.
388 388  
389 -
390 390  |[[image:light.png]]|Although //Analysis// calculations give results for the **global Descartes system**, internal forces can be asked and displayed in arbitrary (reinforcement) directions by checking (% class="wikiinternallink" %)**design forces**(%%) in case of (% class="wikiinternallink" %)**RC design**.
391 391  
392 392  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**(%%):
... ... @@ -471,7 +471,7 @@
471 471  
472 472  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.
473 473  
474 -= Analysis for Maximum of Load Combinations and Groups =
471 += {{id name="Analysis for Maximum of Load Combinations and Groups"/}}Analysis for Maximum of Load Combinations and Groups =
475 475  
476 476  Choosing //Load combinations// for Analysis automatically generates results for the maximum of load combinations too.
477 477  
... ... @@ -512,7 +512,7 @@
512 512  
513 513  Figure: Combination of load cases for maximum of load groups results
514 514  
515 -= Deflection check for RC, steel and timber bars =
512 += {{id name="Deflection check for RC, steel and timber bars"/}}Deflection check for RC, steel and timber bars =
516 516  
517 517  A new checking criteria is available for reinforced concrete, steel and timber bars. Deflection utilization is calculated for //load combinations//, //Maximum of load combinations// and //Maximum of load groups// according to the user defined serviceability limit states.
518 518  
... ... @@ -542,7 +542,6 @@
542 542  |(% style="width:120px" %)[[image:warning.png]]|(% style="width:1322px" %)For columns only this (//“Cantilever and column”//) option is available.|
543 543  
544 544  
545 -
546 546  [[image:1585566012700-385.png]]
547 547  
548 548  
... ... @@ -577,7 +577,7 @@
577 577  
578 578  [[image:1585566101399-508.png]]
579 579  
580 -= Imperfections =
576 += {{id name="Imperfections"/}}Imperfections =
581 581  
582 582  Imperfection calculation is run only for steel bar elements of the structure. Users can add imperfections to a structure in two ways:
583 583  
... ... @@ -588,18 +588,18 @@
588 588  [[image:1585566123852-913.png]]
589 589  Figure: Imperfection calculation by load combination
590 590  \\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//
587 +\\ //critical parameter = critical buckling force/actual load//
592 592  \\or in other words:
593 593  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.
594 594  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.
595 595  \\The factor defines the real imperfect shape, so:
596 -\\\\ //imperfect shape in real dimension = factor * buckling shape//
592 +\\\\ //imperfect shape in real dimension = factor * buckling shape//
597 597  \\[[image:1585566211268-838.png]]
598 598  Figure: Automatic imperfect shape calculation
599 599  
600 600  |[[image:light.png]]|Before imperfection calculation, it is recommended to set minimum 4-5 **//division numbers//** (finite elements) for bars.
601 601  
602 -= Stability Analysis =
598 += {{id name="Stability Analysis"/}}Stability Analysis =
603 603  
604 604  In 3D modules, global stability of the structure can be analyzed automatically if it is requested. Similarly to (% class="wikiinternallink" %)**Imperfections**(%%), the program calculates buckling shapes together with their critical parameters for selected load combinations.
605 605  
... ... @@ -632,7 +632,6 @@
632 632  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.
633 633  )))
634 634  
635 -
636 636  (% style="text-align:center" %)
637 637  [[image:1585566779077-490.png]]
638 638  
... ... @@ -645,10 +645,9 @@
645 645  
646 646  |[[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.
647 647  
648 -
649 649  |[[image:light.png]]|Before stability analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
650 650  
651 -= Eigenfrequencies =
645 += {{id name="Eigenfrequencies"/}}Eigenfrequencies =
652 652  
653 653  == Mass/Vibration shape ==
654 654  
... ... @@ -683,7 +683,6 @@
683 683  
684 684  |(% 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.
685 685  
686 -
687 687  |[[image:light.png]]|(((
688 688  This function is useful to neglect the foundation mass in the eigenfrequency calculation so the total mass contribution in Modal analysis can reach >=90%.
689 689  
... ... @@ -694,12 +694,10 @@
694 694  //Vibration shape//  - vibration shape and associated eigeinfrequency (//Frequency//) and periodic time (//Period//).
695 695  )))
696 696  
697 -
698 698  |(% style="width:109px" %)[[image:light.png]]|(% style="width:1381px" %)(((
699 699  Before dynamic analysis, it is recommended to set minimum 4-5 (% class="wikiinternallink" %)**division numbers**(%%) (finite elements) for bars.
700 700  )))
701 701  
702 -
703 703  == Shear center result ==
704 704  
705 705  FEM-Design can calculate //Shear centers// for each storey of a building. The figures below show a shear center result of an Eigenfrequency calculation.
... ... @@ -710,7 +710,6 @@
710 710  [[image:1585567150564-165.png]][[image:1585567157139-355.png]]
711 711  )))
712 712  
713 -
714 714  |[[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.
715 715  
716 716  [[image:1585567210762-613.png]]
... ... @@ -721,7 +721,7 @@
721 721  
722 722  [[image:1585567234356-994.png]]
723 723  
724 -= Seismic Analysis =
714 += {{id name="Seismic Analysis"/}}Seismic Analysis =
725 725  
726 726  == Methods ==
727 727  
... ... @@ -754,10 +754,7 @@
754 754  [[image:1585303002015-960.png]]
755 755  Figure: Settings of seismic analysis
756 756  
757 -*
758 -
759 -**Static, linear shape**
760 -
747 +* **Static, linear shape**
761 761  As a matter of fact, eigenfrequency calculation is not necessary for this method, because giving the base period time in //x’// and //y’// directions (//Tx’// and //Ty’//) is enough for the calculation. Practically, eigenfrequency calculation performs before setting this data, but these data can be defined using experimental formulas as well. Investigation can be done in //x’// or //y’// direction, or both together.
762 762  
763 763  (% style="width:700px" %)
... ... @@ -767,9 +767,7 @@
767 767  
768 768  |(% style="width:107px" %)[[image:warning.png]]|(% style="width:1383px" %)This method is unusable, if the whole foundation is not in same plane or the horizontal foundation is elastic. In these cases, //Static, mode shape// or //Modal analysis// should be used.
769 769  
770 -*
771 -
772 -**Static, mode shape**
757 +* **Static, mode shape**
773 773  In this method the distribution of “base shear force” happens according to fundamental mode shapes (base vibration shapes).
774 774  
775 775  (% style="width:826px" %)
... ... @@ -784,13 +784,10 @@
784 784  
785 785  |(% style="width:107px" %)[[image:warning.png]]|(% style="width:1383px" %)The calculation of “base shear force” is performed according to the total mass of the structure and not to the effective mass.
786 786  
787 -*
788 -
789 -**Modal analysis**
772 +* **Modal analysis**
790 790  [[image:1585303301268-646.png]]
791 791  \\The essence of the methodis the calculation of the structural response for different ground motions by the sufficient summation of more vibration shapes. Method gives possibility to take into account full //x'//, //y'// and //z// (=global //Z//) direction investigation.
792 792  \\In the table, more vibration mode shape could be selected in //x’//, //y’// and //z //directions if necessary. The last row (orange cells) of the table shows that how large is the sum of the considered effective masses compared to the total or reduced mass of the structure in a given ground motion direction.
793 -
794 794  
795 795  (% style="width:823px" %)
796 796  |(% style="width:95px" %)[[image:light.png]]|(% style="width:725px" %)According to //EC8//, sum of the effective mass of the choosen mode shapes (at least in horizontal direction) should reach 90% of total mass. Additionally every mode shape has to be taken into account where effective mass is larger than 5%.
... ... @@ -803,9 +803,7 @@
803 803  The mode shapes which have small effective mass may be neglected, because their effect in result is very small, but calculation time increases.
804 804  )))
805 805  
806 -*
807 -
808 -**Summation rule by directions**
788 +* **Summation rule by directions**
809 809  According to the //EC8//, the summation rule in the individual directions can be selected. In all other codes always the //SRSS// rule is used for summation (there is no choice). Read more about //SRSS// and //CQC// summation rules in //Theory book//. If the //Automatic// is selected, the rule selection procedure is as follow:
810 810  
811 811  (% style="width:843px" %)
Copyright 2020 StruSoft AB
FEM-Design Wiki