3d Tutorial Multistorage - SOFiSTiK
Tutorial3D multi-storey office buildingSSDSOFiPLUS(-X) SOFiSTiK AG 2008
This manual is protected by copyright laws. No part of it may be translated, copied orreproduced, in any form or by any means, without written permission from SOFiSTiKAG.SOFiSTiK reserves the right to modify or to release new editions of this manual.The manual and the program have been thoroughly checked for errors. However,SOFiSTiK does not claim that either one is completely error free. Errors and omissionsare corrected as soon as they are detected.The user of the program is solely responsible for the applications. We strongly encouragethe user to test the correctness of all calculations at least by random sampling.
Tutorial Fehler! Verweisquelle konnte nicht gefunden werden.Contents1Preface .11.1What is the intention of this tutorial? .11.2What can the tutorial not provide?.11.3Program versions.11.4Legend for this tutorial .12Description of the project.23Why making a 3d-model?.84From the static system to the FEA-model.104.1Preliminary considerations.104.1.1Considerations about the system .104.1.2Considerations about loads and actions.104.1.3Considerations about groups .124.2Modelling the details .134.2.1Connection walls/ columns – slabs.134.2.2Horizontal details .154.2.3Modelling wall pillars .164.3Meshing.174.3.1General hints for system generation.174.3.2Hints for meshing with SOFIMSHB .175Workflow in SSD .196Tutorial example 3D mulit storey office building .206.1Create new SSD project .206.2Define materials and cross sections.216.3Graphical input of system and loads with SOFiPLUS(-X).226.3.1Input of the first floor in 2D .226.3.23D Modelling.316.3.3Additional loads (free loads).526.4Export/ Checks .587Notes . Fehler! Textmarke nicht definiert.8Index of Figures .59Inhaltsverzeichnisi
Tutorial 3D multi-storey office building1Preface1.1What is the intention of this tutorial?This tutorial is an introduction into 3-d modelling of a multi-storey building. It will guide youthrough the whole process of modelling. Having a focus on the general approach of handlinga 3-d model with our software, this example shows you the analysis according to EC 1 and 2.Our graphical user interface, the SOFiSTiK Structural Desktop (SSD) will be used as acommand center. It allows you to control pre-processing, processing and post-processing forthe entire SOFiSTiK Software suite. For the system- and load generation we will useSOFiPLUS(-X).The chosen example of a multistorey office biulding deals only with the upgoing construction.The modelling of basement and foundation will not be discussed here. Please aware that weuse rigid support conditions to simplify the model. This has to be modified for every project.1.2What can the tutorial not provide?The tutorial can neither discuss all program parameters nor substitute the program manuals.We assume a general knowledge for all basic program features. For more information aboutSSD we refer to the basic SOFiSTiK Structural Desktop Tutorial, you will find in the SSDMenu Help Quick Reference .1.3Program versions§SOFiSTiK 23§SOFiPLUS-X 16.4 build 22 or SOFiPLUS 17.1 build 22 with AutoCAD 2007 or higher.1.4Legend for this tutorialSOFiPLUS(-X):§Commands that can/ should be written in the command line begin with an underline(i.e. audit)§All other commands are marked with bold letters and command (i.e. commandstructural line); The commands are availabel via Icon in toolbox or via menu(command line is also possible, but then you have to know the right syntax)§PrefaceIf you have to use the menu, the menu path is signed by a (i.e. file save)1
Tutorial 3D multi-storey office building2Description of the projectFigure 1: Overview buildingThis tutorial will explain how to analyse the multi-storey office building shown in figure 1. Themain structure contains of shear walls, columns, beams and slabs as well as a stiffening core(staircase and elevator).Shear walls and stiffening core support the structure for overall stability. Columns, beamsand walls basically transfer vertical loads. The cladding transfers the wind loads to the floorslabs. It is one element from bottom to top and thus acts like a continuous beam. It alsotransfers the vertical loads on all floor slabs.The building has a width of 12.0 m, a length of 34.6 m and is 19.5 m high. Walls are made ofconcrete C 30/37 and reinforcement steel S 500. The slabs (with T-beams) and alle othercross section are made of C 20/25 and reinforcement steel S 500.The analysis will be done according to Eurocode 2.Description of the project2
Tutorial 3D multi-storey office buildingFigure 2: floor plan and section 1-1Description of the project3
Tutorial 3D multi-storey office buildingAccording to EC1 the following loads have to be considered:Type of loadload valueSelf weight of the structurecalculated by the softwareCladding0,50 kN/m²Allowance for light weight dividing walls1,20 kN/m²Live load (offices, halls )2,00 kN/m²Live load on stairways (here only slabs; staircases 5,00 kN/m²are not modelled; staircase loads are not included)Snow0,75 kN/m²Wind look at the table belowwind in global YY (on the long side)areacpeq [kN/m²]we -0,900H-0,70,75-0,525I00,750,000wallsroof wind in global XX (on the gable side)**areacpeq [kN/m²] we [kN/m2]-0,780wA-1-1,2000,65a h-0,520B-1-0,8000,65l-0,325C-1-0,5000,65l 0,482D-10,7410,65s -0,8000,75l H-0,700,750,150fI0,2/-0,20,75.I with change of sign/ direction** because hight widht wind load area must be divided overhight according to the code Description of the project4
Tutorial 3D multi-storey office buildingFigure 3: example – wind in global Y-direction (shown as filled area and as vector)Description of the project5
Tutorial 3D multi-storey office buildingFigure 4: overview load areas for wind in global X-directionDescription of the project6
Tutorial 3D multi-storey office buildingFigure 5: overview load areas for wind in global Y-directionThis is only a very short description how to define Windloads according to EC 1and how to apply these loads to our examples. A fundamental knowledge of therelevant codes is also necessary.Description of the project7
Tutorial 3D multi-storey office building3Why making a 3d-model?Before starting with the project, let’s discuss the characteristics of 2D versus 3D modelling.2D Modelling3D ModellingWorkflow for a structuresplit construction intostructural members;analyse each memberseparatelyone complex modelInput/ handlingeasy for each member;but often results in a lot ofsingle, independent filescomplex;but only one file for the wholestructureLevel of abstractionhighlowModelling of detailsgood for modelling details,bad for coherencemodelling details notrecommended,good for showing coherenceTime for system generationlittleplentyChanges/ updatesworking processduring by hand for each member;danger to forget something;a lot of workjust once for the whole modelComplexity of modellowHighdanger of black box effectVerifiability (by hand)simplehardQuality of the resultsindependent of the kind of modelling,but depending on the quality of the modelGlobal behaviourstructureofthe hard to predict - imprecisemore precise,e.g. redistribution of forcescan be shownAbility to model and show baddependenciesgoodAnalysis of local stabilityeasyhardDynamic analysishard/ impossibleeasyTime for analysislow for single componentshigh – the whole system hasto be analysedFocus onlocal design (details)global design (main structuralelements)(i.e. earthquake)Why making a 3d-model?8
Tutorial 3D multi-storey office buildingThe table shows that each method has its strengths and weaknesses.2-D and 3-D modelling should be used complementary - or depending on the single jobdefinition - apart.This tutorial will show you the workflow we suggest if you want to use a 3-D model.Nevertheless, this building could also be modelled in 2-D. It is up to the engineer to decide,which model would be best for his project. It is similar to the decision if you want to go toMunich by train, plain or car. With the car, you can make your travel individually, going bytrain is very comfortable and by plane is the fastest way to travel. Each possibility has itsadvantages and disadvantages. Only if you know the whole circumstances, you can makethe best decision.Why making a 3d-model?9
Tutorial 3D multi-storey office building4From the static system to the FEA-model4.1 Preliminary considerationsTo avoid problems during the analysis and design of a 3d-structure we recommend doingsome planning before starting to actually work with the software. As discussed in the lastchapter it is not possible to make a complete design in all details using a 3d-model.4.1.1 Considerations about the systemYou first should make a list of all the design checks you have to make.Based on this list you can decide which components of the structure you have to model andhow far you can simplify these (rule: as simple as possible, but as exact as necessary).Next you should check if some components could be merged to one structural element (e.g.one cross section for similar columns).Making a pre-design of the main structural members (e.g. on a simple beam-model) cansave you a lot of time during the design process and allows you to easily check results. Italso can help if you are not sure how to model details. You can see how big the influence ofthe structural member is on the main structure and if it is worth modelling detailed orsufficient using a coarse model.4.1.2 Considerations about loads and actionsMake a list of all actions and loads (see chapter 2 Description of the project).Define a concept for the load case numbers. SOFiSTiK recommends using load casenumbers smaller than 1000 for single load cases, because numbers larger than 1000 areused for load case combinations by default. It is useful to divide the load cases in smallsections according to their actions. For analyzing this building the following load caseconcept will be used:From the static system to the FEA-model10
Tutorial 3D multi-storey office buildingLoad case(s)Content1 – 99Dead loads1Automatically determined self weight2Dead load in offices/ halls etc.3Dead load cladding100 – 199Live loads on slabs/ roof101 – 113200 – 299Live loadsWind loads201Wind –Y202Wind Y203Wind X; roof 204Wind X; roof -205Wind –X; roof -206Wind –X; roof 300 – 399300SnowSnow on roofKeep your system flexible and upgradeable, i.e. don’t use only consecutive loadcase numbers – if you let some numbers in-between you will be able to add e.g.a “forgotten” load case without changing the whole concept.Number zoneLoad case combinations by default1100 – 1200 (default)SLS – permanent1400 – 1500 (default)SLS – permanent (here: nodal displacements)2100 – 2200 (default)ULSIn some cases the program uses the same load case to save the results ofdifferent superpositions. Nevertheless, the description only shows the name oflast superposition that has been saved with this load case number.If it’s annoying – just rename.From the static system to the FEA-model11
Tutorial 3D multi-storey office building4.1.3 Considerations about groupsWhat means group concept – why should I use groups in my model?Group concept is an classification system to keep your model clear. You canconnect parts of your structure by similarities; i.e. one group for each constructionstage or one group for each cross section .If you define your groups in a resonable way ( group concept) you’ll be able to(de)select a particular structural system, apply loads, analyse and designelements or make graphical post-processings very fast and effective.There is no universal concept for the definition of groups, but it rather depends on theproblem that has to be solved. In one case e.g. it makes sense to define all walls in onegroup and all slabs in another. In another case it might be better to group the elements byfloor level.Using SOFiPLUS-(X) 16.4/17.1 the group-divisor is the same for all groups. Withthe default setting of 10.000 you may use a maximum of 999 groups. Generallyspeaking: the group number multiplied with the group-divisor has to be less than10.000.000.Group divisor means the max. number of (finite) elements in one group. (quads,beams, springs, )Elementnumber of the finite element consists of group number (1st part) andelement number (2nd part).(example: group divisor 10000; finite element 345; group 23 elementnumber 230345)The following table shows how the elements in this example are classified into groups:ComponentFormula for group numberSlabs/ rooflevel number x 100i.e. 1st floor: group number 1 x 100 100Columns(assumingcross section number Level number x 100notmorethandifferent cross sections)50 i.e. column with cross section 1 – ground floor:group number 1 0 x 100 1exception: all dummy beams are in group 49Beamssame group number as the respective slabi.e. T-beam in slab of 1st floor: group number 100Walls(assumingwall number 50 level number x 100 i.e.notmorethandifferent walls on each floor)From the static system to the FEA-model50 wall number 1 in 3rd level:group number 1 50 3 x 100 35112
Tutorial 3D multi-storey office building4.2Modelling the detailsAlthough it is the primary purpose to model a realistic behaviour of the structure, it isimportant to keep your model as simple as possible. It is worth spending some time thinkingabout the details to avoid mistakes and get the most efficient model. Having a model withfewer elements can not only save a lot of calculation time but will also help to understandresults.Modelling the details is not only depending on the specifics of FEA but also on theconstruction sequence as well as on good engineering practice. In the following some detailsand decisions for the multi-storey office building will be discussed.4.2.1 Connection walls/ columns – slabsFollowing comments are made for walls, but in general meaning they are alsohold for true for connetions column-slab.Basically there are two possibilities how to model the connection between walls and slabs:a) rigid connectionb) hinged connectionFor the input of the model it is easier to choose a rigid connection because this is the defaultsetting in SOFiPLUS(-X). But you have to consider this effect when planning thereinforcement.If using a hinged connection there is no analytical bending moment between the slab and thewall. Therefore planning and building the reinforcement is a lot easier.The true structural behaviour is somewhere in-between case a) and b). Thus it is up to thestructural engineer how to model the connections. Tables Table 1 (vertical modeling details;page 14) and Table 2 (vertical modeling details; page 15) show what decisions were madefor the multi-storey office building of this tutorial.From the static system to the FEA-model13
Tutorial 3D multi-storey office building13245Figure 6: overview vertical connection detailsDescription (number of details – please look at Figure 6: overview verticalconnection details)Case 1: exterior wall –roof hinge on top of wall the middle axis of walls is moved to the real borderline of the building; so the wallelements in the model have their nodes in the middle, but wall is slightly moved (onthe conservative side)Case 2: interior wall - roof hinge on top of wallCase 3: floor slab - exterior wall hinge in floor slab wall acts like a continous beamCase 4: interior (core) wall on slab hinges on top and bottom wall floor slab acts as continuous beamCase 5: columns all columns are modelled as pin-ended columns from slab to slabTable 1: vertical modeling details – connection walls/columns ó slabs/ roofFrom the static system to the FEA-model14
Tutorial 3D multi-storey office building4.2.2 Horizontal details41235Figure 7: overview horizontal modelling detailsDescriptionCase 1: exterior wall ó real slab dimensions/ mesh to avoid bends in system lines (which are not existing in reality) and singularities inthe mesh, the system line of the wall is set to the boundary of the slab (instead of 1/3line of the wall)Case 2: interior wall system line middle line of the wallCase 3: interior walls around opening avoiding bends in system line by choosing middle line for the wall at right, because itis small compared to the adjacent wall other walls analogous to case 1Case 4: column support Model as a single structural point (with input of dimension for punching)Case 5: downstand beam downstand beams are modelled directly inside the slab using a structural line withbeam properties (the program takes care of the downstand beam - for furtherinformation please see our paper t-beam philosophy).Table 2: horizontal modeling detailsFrom the static system to the FEA-model15
Tutorial 3D multi-storey office buildingAnother usual case is a column close to a border of a slab (i.e. real column dimension isequal to the border of the slab), but the center point of the column is in the slab. In thosecases you should model the edge column directly on the boundary. This will result in a betterFE mesh (the minimum increase in span width is usually negligible)Figure 8: Modelling edge columns close to the borderline4.2.3 Modelling wall pillarsFor wall pillars, you have to decide whether it is better to model a column using beamelement
SOFiSTiK AG 2008 Tutorial 3D multi-storey office building SSD SOFiPLUS(-X) This manual is protected by copyright laws. No part of it may be translated, copied or reproduced, in any form or by any means, without written permission from SOFiSTiK AG.
reproduced, in any form or by any means, without written permission from SOFiSTiK AG. SOFiSTiK reserves the right to modify or to release new editions of this manual. The manual and the program have been thoroughly checked for errors. However, SOFiSTiK . This Tutorial provides you with a short overview and by means of simple examples a fast
SOFiSTiK AG 2010 Tutorial SSD / SOFiPLUS - A Quick Reference SSD Version 2010 SOFiPLUS(-X) Version 2010 . This manual is protected by copyright laws. No part of it may be translated, copied or reproduced, in any form or by any means, without written permission from SOFiSTiK AG.
SOFiSTiK AG 2011 Tutorial 3D Multi-Storey Office Building SSD/SOFiPLUS(-X) Version 2010 . This manual is protected by copyright laws. No part of it may be translated, copied or reproduced, in any form or by any means, without written permission from SOFiSTiK AG.
1—7 SOFiPLUS_Tutorial_IGH.docf 1. BASIC The core of the SOFiSTiK program is a very efficient data base (CDBASE). The Group of programs is able to solve different problems from structural analysis to interchange data through the data base. SOFiSTiK consists of a large number of modules which communicate with each other either
SOFiSTiK AG 2008 Quick Start Guide Prestressd Slabs . Example page 1 Prestressed Slab 1 Scope Slab prestressing provides an economical way to decrease the amount of required reinforcement (ULS) while allowing for larger spans with slender slabs and better
Casimir Katz, SOFiSTiK AG, Oberschleißheim ir. Henk Krüs, Cyclone Fluid Dynamics BV, Waalre Zusammenfassung: Der Einsatz von CFD im Bauwesen stellt nach wie vor eine Nischenanwendung dar. Die Gründe dafür werden beleuchtet und aufgezeigt, warum sich das jetzt ändern wird.
Tutorial Process The AVID tutorial process has been divided into three partsÑ before the tutorial, during the tutorial and after the tutorial. These three parts provide a framework for the 10 steps that need to take place to create effective, rigorous and collaborative tutorials. Read and note the key components of each step of the tutorial .
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