Wiki source code of Steel Design

Last modified by Fredrik Lagerström on 2020/04/03 11:30
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1 {{box cssClass="floatinginfobox" title="**Contents**"}}
2 {{toc/}}
3 {{/box}}
4
5 Fast auto design and check are available to find the most suitable steel bar profiles. All section shapes and classes - including class 4 profiles (slender sections) - can be checked for utilization. When modeling steel bars with 3D steel shell components, an auto design finds the proper thickness of the shell elements.
6
7 The table summarizes the available steel design features by FEM-Design module.
8
9 (% class="table-hover" style="width:516px" %)
10 |(% style="background-color:#0076cb; width:170px" %)(% style="color:#ffffff" %)**Design element type**|(% style="background-color:#0076cb; width:151px" %)(% style="color:#ffffff" %)**Design feature**|(% style="background-color:#0076cb; text-align:center; width:62px" %)[[image:1585653000367-149.png]]|(% style="background-color:#0076cb; text-align:center; width:68px" %)[[image:1585653005373-969.png]]|(% style="background-color:#0076cb; text-align:center; width:62px" %)[[image:1585653010914-897.png]]
11 |(% style="width:170px" %)[[image:1585652787092-597.png]] //Steel Bar//|(% style="width:151px" %)//Auto design//|(% style="text-align:center; width:62px" %)[[image:1585653017267-997.png]]|(% style="text-align:center; width:68px" %)[[image:1585653021432-508.png]]|(% style="text-align:center; width:62px" %)[[image:1585653024373-352.png]]
12 |(% style="width:170px" %) |(% style="width:151px" %)//Manual design//|(% style="text-align:center; width:62px" %)[[image:1585653019098-174.png]]|(% style="text-align:center; width:68px" %)[[image:1585653023020-114.png]]|(% style="text-align:center; width:62px" %)[[image:1585653025839-878.png]]
13 |(% style="width:170px" %)[[image:1585652994519-156.png]] //Shell Model//|(% style="width:151px" %)//Auto design//|(% style="text-align:center; width:62px" %) |(% style="text-align:center; width:68px" %) |(% style="text-align:center; width:62px" %)[[image:1585653027225-956.png]]
14 |(% style="width:170px" %) |(% style="width:151px" %)//Manual design//|(% style="text-align:center; width:62px" %) |(% style="text-align:center; width:68px" %) |(% style="text-align:center; width:62px" %)[[image:1585653029231-967.png]]
15
16 Table: Steel design features by FEM-Design module
17
18 = {{id name="Steel Bar"/}}Steel Bar =
19
20 Global** **//Auto (steel bar) design// (//Calculate > Design calculations > Auto design all structural elements//) finds the most suitable cross-section (from the profile range set at //Auto design > Parameters//) for all steel bars (columns, beams and truss members) based on their buckling length, stiffeners, calculation parameters, internal forces and detailed utilization calculations. With //Manual design// you can run quick utilization check for given profiles by bar elements and/or design groups. You can also do quick //Auto design// by elements and design groups only instead of global design. Of course, any number of design cycles is executable, so the global //Auto design// can be combined with both previous and additional element-based //Auto designs//.
21
22 (% class="table-bordered" style="width:863px" %)
23 |(% style="background-color:#0076cb; width:46px" %)(% style="color:#ffffff" %)**No.**|(% style="background-color:#0076cb; width:244px" %)(% style="color:#ffffff" %)**Global steel bar design**|(% style="background-color:#0076cb; width:286px" %)(% style="color:#ffffff" %)**Element-based steel design**|(% style="background-color:#0076cb; width:285px" %)(% style="color:#ffffff" %)**Combined steel design**
24 |(% style="width:46px" %)1|(% style="width:244px" %)[[image:1585653335569-348.png]] Calculation parameters|(% style="width:286px" %)[[image:1585653395657-131.png]] Global //Analysis//|(% style="width:285px" %)[[image:1585653406580-206.png]] Calculation parameters
25 |(% style="width:46px" %)2|(% style="width:244px" %)[[image:1585653342083-533.png]] //Design group//|(% style="width:286px" %)[[image:1585653404253-498.png]] Calculation parameters|(% style="width:285px" %)[[image:1585653345774-816.png]] //Design group//
26 |(% style="width:46px" %)3|(% style="width:244px" %)[[image:1585653356186-514.png]] [[image:1585653414535-767.png]] //Auto design > Parameters//|(% style="width:286px" %)[[image:1585653343851-773.png]] //Design group//|(% style="width:285px" %)[[image:1585653366182-867.png]] [[image:1585653420228-806.png]] //Auto design > Parameters//
27 |(% style="width:46px" %)4|(% style="width:244px" %)[[image:1585653390033-860.png]] Global //Auto design//|(% style="width:286px" %)[[image:1585653357667-370.png]] [[image:1585653416268-549.png]] //Auto design > Parameters//|(% style="width:285px" %)[[image:1585653393231-466.png]] Global //Auto design//
28 |(% style="width:46px" %)5|(% style="width:244px" %)[[image:1585653373155-845.png]] [[//Documentation//>>doc:Manuals.User Manual.Documentation.WebHome]]|(% style="width:286px" %)[[image:1585653359638-555.png]] [[image:1585653452601-397.png]] //Auto design// by elements|(% style="width:285px" %)[[image:1585653361783-576.png]] [[image:1585653418161-343.png]] //Auto design > Parameters//
29 |(% style="width:46px" %)6|(% style="width:244px" %) |(% style="width:286px" %)[[image:1585653462586-867.png]] //Manual// //design// by elements|(% style="width:285px" %)[[image:1585653364720-610.png]] [[image:1585653430288-923.png]] //Auto design// by elements
30 |(% style="width:46px" %)7|(% style="width:244px" %) |(% style="width:286px" %)[[image:1585653470339-646.png]] //Apply design changes//|(% style="width:285px" %)[[image:1585653464271-136.png]] //Manual design// by elements
31 |(% style="width:46px" %)8|(% style="width:244px" %) |(% style="width:286px" %)[[image:1585653385299-391.png]] Global //Check//|(% style="width:285px" %)[[image:1585653471928-565.png]] //Apply design changes//
32 |(% style="width:46px" %)9|(% style="width:244px" %) |(% style="width:286px" %)[[image:1585653375446-115.png]] [[//Documentation//>>doc:Manuals.User Manual.Documentation.WebHome]]|(% style="width:285px" %)[[image:1585653387844-184.png]] Global //Check//
33 |(% style="width:46px" %)10|(% style="width:244px" %) |(% style="width:286px" %) |(% style="width:285px" %)[[image:1585653379131-325.png]] [[//Documentation//>>doc:Manuals.User Manual.Documentation.WebHome]]
34
35 Table: Recommended steps by design alternatives
36
37 == Initial Calculation and Design Parameters ==
38
39 All bar design calculations needs internal forces from //Analysis// calculations applied for //Load combinations// or //Load-groups//, [[image:1585653527641-768.png]] //Buckling length// and initial design settings defined by [[image:1585653534035-284.png]] //Design calculation parameters//.
40
41 [[image:1585653539785-232.png]]
42
43 Figure: Design calculation parameters
44
45 The //flexural buckling curves// (EN1993-1-1: 6.3.1.2) can be specified for each steel bar in Calculation parameters dialog or the user can let the program to calculate it as in the previous versions by selecting “Auto” option.
46
47 The method for considering imperfections of bars has to be selected, there are three types:
48
49 * Ignore 2^^nd^^ order analysis: The internal forces comes from the 1^^st^^ order results.
50 * Consider 2^^nd^^ order analysis, if available: The internal forces comes from the 2^^nd^^ order results.
51 * 2^^nd^^ order internal forces + 1^^st^^ order design: The internal forces comes from the 2^^nd^^ order results, but the design calculation will be linear.
52
53 (% style="text-align:center" %)
54 [[image:1585653625140-439.png]]
55
56 (% style="text-align: center;" %)
57 Figure: Setting calculation parameters
58
59 |(% style="width:103px" %)[[image:warning.png]]|(% style="width:1387px" %)For steel bars with varying section the “Auto” option cannot display the automatically calculated curve, since it is determined during the design calculation.
60
61 |(% style="width:103px" %)[[image:warning.png]]|(% style="width:1387px" %)When the section of a steel bar is modified, buckling curve options of the calculation parameter is reset to “Auto”
62
63 |(% style="width:103px" %)[[image:warning.png]]|(% style="width:1387px" %)When buckling curve is calculated automatically, applied section is considered, if it exist.
64
65 //Convergence criteria// and the //maximum number of iteration steps// can be set for effective cross-section calculation of Class 4 steel bar section in Calculation parameters dialog.
66
67
68 |(% style="width:103px" %)[[image:light.png]]|(% style="width:1387px" %)In some cases the iteration for effective cross-section fails because of the too strong convergence criteria. In this case reducing its factor or increasing the number of the iteration steps may solve the problem.
69
70 |(% style="width:103px" %)[[image:light.png]]|(% style="width:1387px" %)Lateral torsional buckling can be calculated using the formulas to general case instead of using the simplified method.When the general method is used for lateral torsional buckling calculation, the position of the load needs to be specified as well. Calculation method of the k,,ij,, interaction factors can be specified by selecting the design configuration option from the ribbon.
71
72 For lateral torsional buckling the program can separate to top flange and bottom flange stability loss. In the following picture the top flange and it’s corresponding force is red and the bottom is blue.
73
74 [[image:1585653897756-170.png]]
75
76 [[image:1585653864181-921.png]]
77
78 [[image:1585653874937-809.png]]
79
80
81 Beta factors for all 4 direction-stability loss method are separate from each other.
82
83 [[image:1585653911563-415.png]]
84
85 To copy buckling lengths from one bar to another use the Copy buckling length command and:
86
87 * Select the types to copy
88 * Select the source bar
89 * Select the destination bar
90
91 [[image:1585653925026-645.png]]
92
93
94 |(% style="width:55px" %)(((
95 [[image:1585653936189-224.png]]
96 )))|(% style="width:1435px" %)(((
97 Stiffeners can be added manually to steel bars at any time during design (e.g. before //Auto design//, or between //Auto design// and final //Check//). Stiffeners can be defined element by element, but they can be copied among bar elements. Stiffener definition tools are:
98
99 * [[image:1585653964846-534.png]] creates given number of evenly distributed stiffeners on a defined length section,
100 * [[image:1585653970730-422.png]] creates stiffeners by given distance on a defined length section (in case the multiple of the distance does not fit in the section, the program distributes stiffeners with equal parts at the ends),
101 * [[image:1585653976146-643.png]] defines stiffeners one by one in given position,
102 * [[image:1585653981351-820.png]] copies stiffeners of a selected bar to other bars with the same length.
103 )))
104
105 You can increase the number of stiffeners in more steps, if you inactivate [[image:1585653994855-683.png]] (//Do not delete the original//).
106
107 (% style="text-align:center" %)
108 [[image:1585653999999-142.png]]
109
110 (% style="text-align: center;" %)
111 Figure: Stiffeners
112
113 == Auto Design ==
114
115 |(% style="width:52px" %)(((
116 [[image:1585654027068-138.png]]
117 )))|(% style="width:1438px" %)Global// Auto design// gives utilization results and suitable profiles for all steel bars of the current project.
118
119 [[image:1585654045991-869.png]]
120
121 Figure: Global Auto design and utilization result
122
123 |(% style="width:101px" %)[[image:light.png]]|(% style="width:1389px" %)(((
124 The recommended profile names can be displayed on screen by showing the “//Steel bar, applied quantity//” object layer, or click [[image:1585654110042-729.png]] //Design// tool of the //Auto design// and the parameters together with utilization results are available in table format. Utilization as colored figure (color palette) can be displayed by selecting //New result > Steel bar > Utilization//.
125 )))
126
127 |(% style="width:104px" %)[[image:warning.png]]|(% style="width:1386px" %)Variable cross-section steel bars can’t be designed, just checked.
128
129 Applied profiles are displayed in blue in the //Utilization// table, if they are assigned to the steel bars during design, otherwise black color represents the original/initial profiles.
130
131
132 |(% style="width:80px" %)(((
133 [[image:1585654149668-849.png]]
134 )))|(% style="width:1410px" %)Element-based //Auto design// finds the most suitable profile of steel columns, beams and bars for selected unique or grouped members only from a range of available profiles defined by [[image:1585654169799-983.png]] //Parameters//. The design utilization can be limited between 10% and 100% with //Limit utilization//.
135
136 (% style="text-align:center" %)
137 [[image:1585654175373-259.png]]
138
139 (% style="text-align: center;" %)
140 Figure: Range of available profiles for design
141
142 To run element-based design for the load combinations or the maximum of load groups, select the required members and/or group with the //Auto design// command and click [[image:1585654188559-688.png]] //Design// tool. The quick process results recommended profiles and their utilization. Check the //Display table// box to have a look at the overall design results (see the figure before).
143
144 The upper table shows the design efficiency and the maximal utilization of the designed single members and groups based on the given design parameters. The bottom table displays the utilization details of the bar or the members of the group selected in the upper table.
145
146
147 (% class="table-hover" %)
148 |(% style="background-color:#0076cb" %) |(% style="background-color:#0076cb; width:574px" %)(% style="color:#ffffff" %)**Meaning**|(% style="background-color:#0076cb; width:717px" %)(% style="color:#ffffff" %)**Note**
149 |[[image:1585654219128-709.png]]|(% style="width:574px" %)Suitable profile is available|(% style="width:717px" %)
150 |[[image:1585654225863-981.png]]|(% style="width:574px" %)Suitable profile is not available|(% style="width:717px" %)Modify the range of available profiles or steel materials
151 |[[image:image-20200331133035-1.png]]|(% style="width:574px" %)Suitable profile is available, but the utilization is over the //Limit utilization//|(% style="width:717px" %)
152 |Group|(% style="width:574px" %)ID of a single bar or a group name|(% style="width:717px" %)
153 |Design parameters|(% style="width:574px" %)The defined range of available profiles|(% style="width:717px" %)
154 |Applied profile|(% style="width:574px" %)Profile currently assigned to the bar|(% style="width:717px" %)
155 |Max|(% style="width:574px" %)Max. utilization of a single bar or the significant member of a group|(% style="width:717px" %)
156 |Min|(% style="width:574px" %)Max. utilization of the less significant group member|(% style="width:717px" %)
157 |Bar|(% style="width:574px" %)ID of a single bar or a group member|(% style="width:717px" %)
158 |RCS|(% style="width:574px" %)Resistance of cross-section: the maximum utilization from all strength calculations|(% style="width:717px" %)(((
159 According to Eurocode 3: 6.2.3 - 6.2.10
160 )))
161 |FB|(% style="width:574px" %)Utilization for flexural buckling|(% style="width:717px" %)According to Eurocode 3: 6.3.1
162 |TFB|(% style="width:574px" %)Utilization for torsional-flexural buckling|(% style="width:717px" %)According to Eurocode 3: 6.3.1
163 |LTB|(% style="width:574px" %)Utilization for lateral torsional buckling|(% style="width:717px" %)According to Eurocode 3: 6.3.2.4
164 |SB|(% style="width:574px" %)Utilization for shear buckling|(% style="width:717px" %)According to Eurocode 3: 1-5: 5
165 |IA|(% style="width:574px" %)(((
166 Interaction (between normal force and bending)
167 )))|(% style="width:717px" %)According to Eurocode 3: 6.3.3
168
169 Table: The meaning of symbols, design parameters and utilization results
170
171 Quick redesign can be done inside the //Utilization// table:
172
173 1. Select a bar or a design group in the upper table.
174 1. Modify the range of available profiles for the select element under //Parameters//.
175 1. Click //Design//.
176
177 //Save /load default sections//
178
179 (% style="text-align:center" %)
180 [[image:1585654286704-109.png]]
181
182 For each section type (e.g. IPE, HEA, CHS, etc.) a set of sections can be saved/loaded as default.
183
184 This will only work with //one type// cross-section (e.g. only HEA, or only KKR) selected. Otherwise, with //Save// command, the user can save a set of arbitrary sections into a file, and use them later for another model by //Load// command.
185
186 == Manual Design ==
187
188 |(% style="width:82px" %)[[image:1585654369126-597.png]]|(% style="width:1408px" %)With //Manual design// quick utilization check can be done for given steel profile and for selected steel beam, column, bar or design group only. Just, choose the load type (load combination or load group) and a profile name from the drop-down lists and select a bar, bars or group, and program displays detailed utilization results in table format.
189
190 |(% style="width:104px" %)[[image:warning.png]]|(% style="width:1386px" %)The meaning of the utilization components, the table content and features are the same as written before at //Auto design//. The program use the chosen profile for all selected bar elements.
191
192 [[image:1585654421650-656.png]]
193
194 Figure: Quick check by Manual design
195
196 == Detailed Result ==
197
198 Utilization of steel bars can be displayed in the following cases:
199
200 * After global //Auto design//, you can display utilization of all steel bars checked for the recommended profiles.
201 * When running element-based //Auto design//, utilization can be displayed by designed elements.
202 * After //Manual design//, element-based //Check// displays utilization for selected elements.
203 * After global //Check// done for all bar elements having final cross-section.
204
205 |(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)No.|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Global Auto design**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Element-based Auto des.**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Element-based Check**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Global Check**
206 |1|[[image:1585654467668-415.png]]// Calculate > Design calculation > Auto design all structural elements//|[[image:1585654540697-926.png]] //Auto design//|(((
207 [[image:1585654546499-492.png]] //Auto design// and/or
208
209 [[image:1585654532071-809.png]] //Manual design//
210 )))|(((
211 [[image:1585654550973-239.png]] //Auto design// and/or
212
213 [[image:1585654533943-756.png]] //Manual design//
214 )))
215 |2|(((
216 [[image:1585654490458-637.png]]// New result > Steel bar//
217 )))|[[image:1585654497465-658.png]]// New result > Steel bar//|[[image:1585654527003-278.png]] //Check//|[[image:1585654521036-969.png]] Apply changes
218 |3| | |[[image:1585654500812-499.png]] //New result > Steel bar//|[[image:1585654471339-281.png]] //Calculate > Design calculation > Auto design all structural elements//
219 |4| | | |(((
220 [[image:1585654508830-980.png]] //New result > Steel bar//
221 )))
222
223 Table: Steps of displaying steel bar utilization by different design cases
224
225 |[[image:1585654569187-921.png]]|Utilization displayed with //New result// appears for all designed bars. The utilization components for a bar/design group can be displayed with //Detailed result//.
226
227 //Detailed result// opens a new window in the current project after selecting a bar/group member, which displays:
228
229 * **Input data**
230 The figure displays the applied steel cross-section with its main calculation and material parameters.
231 \\[[image:1585654590787-377.png]]
232 Figure: Applied cross-section
233
234 * **Detailed calculation formulas**
235 Calculation details and final values are collected by checking types:
236 ** //Shear resistance// (Eurocode3: 1-1: 6.2.6, 6.2.8),
237 ** //Torsional resistance// (1-1: 6.2.7),
238 ** //Shear stress// (1-1: 6.2.6),
239 ** //Normal stress// (1-1: 6.2.1),
240 ** //Normal capacity// (1-1: 6.2.1),
241 ** //Flexural buckling //(1-1: 6.3.1),
242 ** //Torsional-flexural buckling //(1-1: 6.3.1),
243 ** //Lateral-torsional buckling //(1-1: 6.3.2.4),
244 ** //Interaction between normal force and bending// (1-1: 6.3.3.) and
245 ** //Shear buckling //(1-5: 5).
246 \\The proper results are displayed in green, while the red result warnings you to repeat design with new bar properties. The content of the utilization checks depends on //Display options//. Not relevant checks can also be hidden.
247 \\[[image:1585654617784-697.png]]
248 Figure: Utilization checks and formulas
249
250 * **Summary graph**
251 //Summary// graph is displayed with legend by default. Numeric values can be inquired in the calculation sections (set by //Design calculation parameters//).
252 \\[[image:1585654637081-726.png]]
253 Figure: Utilization summary
254
255 [[image:1585654653485-447.png]]// Tabmenu// contains the following tools and settings:
256
257 * **Selection of element to display**
258 You can choose a unique or a design group member from the drop-down lists to display its detailed results mentioned before. Each row displays the ID and the maximum utilization of a member. In case of a design group, “Maximum” means each check is displayed for the significant member having the maximum utilization for that check.
259 \\[[image:1585654758567-477.png]]
260 Figure: Selection of a unique or a group member
261 * **Selection of design load**
262 Depending on steel design was done for load combinations or load groups, a load combination or the maximum or a significant component of load groups can be selected for detailed results. Each row displays the name of the load combination/load group component and its utilization effect. “Maximum” means each check is displayed for the significant load combination or component of load groups having the maximum utilization for that check.
263 \\[[image:1585654775005-862.png]]
264 Figure: Selection from design loads
265 * [[image:1585654862323-747.png]]** Auto design**
266 Quick //Auto design// can be done for the currently displayed unique/group member. Its design parameters can be set/modified in the appearing dialog, and then clicking //OK// starts steel design that updates all detailed result figures and formulas.
267 * [[image:1585654855258-686.png]]** Manual design**
268 //Manual design// can be launched directly for the currently displayed unique member /group.
269 * [[image:1585654845984-672.png]] **Display options**
270 The content and the appearance of the detailed result can be set with //Display options//. You can show only the final equation without details of the different checks (//Hide details//).
271 [[image:1585654839027-624.png]]
272 Figure: Display options of Detailed result
273 * **Go to**
274 Navigate in the detailed result window by selecting the required design type in the drop-down list. It is useful when you are in zoomed view.
275
276 [[image:1585654880904-396.png]] Click //Tools > Add view to document// to place all figures, fomulas and summary table or specified details only into [[//Documentation//>>doc:Manuals.User Manual.Documentation.WebHome]].
277
278 == Fire design for steel bars ==
279
280 //Fire design// gives the opportunity to check and design steel bars for fire effects according to EN 1993-1-2.
281
282 Launch //Steel design/ Steel bar, fire design .// To start //Fire design// it needs some new input data of the bars, and a special load combination and/or load group must be defined.
283
284 * A „+Fire” type load case has to be defined in the //Load cases// dialog.
285 [[image:1585654903292-534.png]]
286 * For maximum of load groups calculations, an accidental load group must be defined that contains the „+Fire” type load case.
287 [[image:1585654913288-557.png]]
288 * For maximum of load combinations calculations, accidental load combinations must be defined that contains the „+Fire” type load case.
289 [[image:1585654926562-624.png]]
290 * The effects (internal forces) are calculated from accidental load combinations, where fire is the accidental effect. Resistance of bar is calculated by using reduced yield strength and elasticity modulus for steel at the elevated temperature.
291
292 //Fire design// contains //Calculation parameter, Check, Design group, Auto design //and// Manual design //commands.
293
294 === **Calculation parameter** ===
295
296 Explanation of data in calculation parameters are in EN 1993-1-2:3, 4 and EN 1992-1-2:3.
297
298 „Deflection criterion is essential” option is available for Danish national annex only.
299
300 [[image:image-20200331125036-34.png]]
301
302 === **Check** ===
303
304 It works in exactly the same way as in case of steel bar design.
305
306 === **Design group** ===
307
308 It works in exactly the same way as in case of normal steel bar design, except that fire design parameter and fire design calculation parameter of two bars must match to be placed into the same design group.
309
310 === **Auto design** ===
311
312 There are two design options:
313
314 * //Design for fire protection material//
315 The design parameter contains the fire protection material, which can be selected from a library (see later). Its //minimal and maximal thickness// and an increment value, which is used by the automatic design procedure to find the minimal necessary thickness of the protection material, can be given by the User
316 * //Calculate maximum temperature// 
317 The //Temperature// //step //for maximum temperature calculation can be defined by the User.
318
319 //Limit utilization// can also be set in the Steel bar - fire design parameter dialog
320
321 [[image:1585654983150-702.png]]
322
323 === **Manual design** ===
324
325 Fire protection material (from a library, see later), its thickness, or the //Maximum member temperature// can be selected in Steel bar, fire protection dialog for Manual Design..
326
327 [[image:1585655000724-715.png]]
328
329 === **Fire protection material library** ===
330
331 It is available by clicking on „Edit library…” item in the material list of fire protection parameter in Auto and Manual design dialogs.
332
333 [[image:1585655010127-795.png]]
334
335 === **Results** ===
336
337 Utilization results are available to display on the model and to list.
338
339 A new result “Max. of combinations/Bar, Combined utilization summary” is available, where the maximum utilization of steel bars for both normal and fire check is displayed
340
341 [[image:1585655021923-512.png]]
342
343
344 [[image:1585655030224-469.png]]
345
346 = {{id name="Shell Model"/}}Shell Model =
347
348 In FEM-Design, a steel bar can be modeled as a real 3D element defined from steel plates.
349
350 |[[image:light.png]]|To convert a bar element to 3D shells apply the //Steel bar, shell model// tool of the [[image:1585655069838-323.png]] //Tabmenu//.
351
352 Global** **//Auto (Shell model) design// (//Calculate > Design calculations > Auto design all structural elements//) finds the most suitable thickness (from a thickness range set at //Auto design > Parameters//) for all steel plates of the shell model based on internal forces, stability check and detailed utilization calculations. With //Manual design// you can run quick utilization check of given thickness values for selected shell models or their design groups. You can also do quick //Auto design// by shell elements and design groups only instead of global design. Of course, any number of design cycles is executable, so the global //Auto design// can be combined with both previous and additional element-based //Auto designs//.
353
354
355 (% style="width:854px" %)
356 |(% style="background-color:#0076cb; width:48px" %)(% style="color:#ffffff" %)**No.**|(% style="background-color:#0076cb; width:292px" %)(% style="color:#ffffff" %)**Global steel bar design**|(% style="background-color:#0076cb; width:257px" %)(% style="color:#ffffff" %)**Element-based steel design**|(% style="background-color:#0076cb; width:254px" %)(% style="color:#ffffff" %)**Combined steel design**
357 |(% style="width:48px" %)1|(% style="width:292px" %)[[image:1585655110330-554.png]] //Structure > Steel bar,shell model//|(% style="width:257px" %)[[image:1585655112103-544.png]] //Structure > Steel bar,shell model//|(% style="width:254px" %)[[image:1585655114374-463.png]] //Structure > Steel bar,shell model//
358 |(% style="width:48px" %)2|(% style="width:292px" %)[[image:1585655129235-663.png]] //Design group//|(% style="width:257px" %)[[image:1585655158010-179.png]] Global //Stability analysis//|(% style="width:254px" %)[[image:1585655132593-110.png]] //Design group//
359 |(% style="width:48px" %)3|(% style="width:292px" %)[[image:1585655138550-962.png]] [[image:1585655180397-125.png]] //Auto design > Parameters//|(% style="width:257px" %)[[image:1585655130886-154.png]] //Design group//|(% style="width:254px" %)[[image:1585655142069-589.png]] [[image:1585655185013-286.png]] Design //Parameters//
360 |(% style="width:48px" %)4|(% style="width:292px" %)[[image:1585655155928-228.png]] Global //Auto design//|(% style="width:257px" %)[[image:1585655140288-697.png]] [[image:1585655181897-706.png]] //Auto design > Parameters//|(% style="width:254px" %)[[image:1585655161783-439.png]] Global //Auto design//
361 |(% style="width:48px" %)5|(% style="width:292px" %)[[image:1585655169306-415.png]] [[(% class="wikiinternallink" %)//Documentation//>>path:/xwiki/wiki/femdesignwiki/get/Manuals/User%20Manual/Steel%20Design/?sheet=CKEditor.ResourceDispatcher&outputSyntax=plain&language=en&type=doc&reference=Manuals.User+Manual.Documentation.WebHome&typed=true]]|(% style="width:257px" %)[[image:1585655143460-852.png]] [[image:1585655192442-628.png]] //Auto design// by elements|(% style="width:254px" %)[[image:1585655148998-886.png]] [[image:1585655186607-680.png]] //Auto design > Parameters//
362 |(% style="width:48px" %)6|(% style="width:292px" %) |(% style="width:257px" %)[[image:1585655199189-297.png]] //Manual design// by elements|(% style="width:254px" %)[[image:1585655146290-327.png]] [[image:1585655194279-860.png]] //Auto design// by elements
363 |(% style="width:48px" %)7|(% style="width:292px" %) |(% style="width:257px" %)[[image:1585655206657-954.png]] //Apply design changes//|(% style="width:254px" %)[[image:1585655200908-342.png]] //Manual design// by elements
364 |(% style="width:48px" %)8|(% style="width:292px" %) |(% style="width:257px" %)[[image:1585655159689-227.png]] Global //Check//|(% style="width:254px" %)[[image:1585655208027-158.png]] //Apply design changes//
365 |(% style="width:48px" %)9|(% style="width:292px" %) |(% style="width:257px" %)[[image:1585655170704-910.png]] [[(% class="wikiinternallink" %)//Documentation//>>path:/xwiki/wiki/femdesignwiki/get/Manuals/User%20Manual/Steel%20Design/?sheet=CKEditor.ResourceDispatcher&outputSyntax=plain&language=en&type=doc&reference=Manuals.User+Manual.Documentation.WebHome&typed=true]]|(% style="width:254px" %)[[image:1585655163454-965.png]] Global //Check//
366 |(% style="width:48px" %)10|(% style="width:292px" %) |(% style="width:257px" %) |(% style="width:254px" %)[[image:1585655173659-102.png]] [[(% class="wikiinternallink" %)//Documentation//>>path:/xwiki/wiki/femdesignwiki/get/Manuals/User%20Manual/Steel%20Design/?sheet=CKEditor.ResourceDispatcher&outputSyntax=plain&language=en&type=doc&reference=Manuals.User+Manual.Documentation.WebHome&typed=true]]
367
368 Table: Recommended steps by design alternatives
369
370 |[[image:warning.png]]|//Stability analysis// is required to get utilization check of steel bar-shell models. Global //Auto design// automatically runs stability analysis for the entire structure.
371
372 == Auto Design ==
373
374 [[image:1585655270335-250.png]] Global// Auto design// gives utilization results and suitable thickness for all steel plates of shell models.
375
376
377 (% style="text-align:center" %)
378 [[image:1585655276057-309.png]]
379
380 (% style="text-align: center;" %)
381 Figure: Global Auto design and utilization result
382
383 |(% style="width:116px" %)[[image:light.png]]|(% style="width:1374px" %)(((
384 The recommended thickness values can be displayed on screen by showing the “//Steel bar, shell model, applied quantity//” object layer, or click [[image:1585655329187-466.png]] //Design// tool of the //Auto design// and the thickness values together with utilization results are available in table format. Utilization as colored figure (color palette) can be displayed by selecting //New result > Steel bar, shell model > Utilization//.
385 )))
386
387 Applied thickness values are displayed in blue in the //Utilization// table, if they are assigned to the steel shell parts during design, otherwise black color represents the original/initial thickness.
388
389 |(% style="width:63px" %)[[image:1585655357850-434.png]]|(% style="width:1427px" %)Element-based //Auto design// finds the most suitable thickness of steel plates for selected unique or grouped shell models only from a range of available thicknesses defined by [[image:1585655373290-257.png]]// Parameters//.
390
391 [[image:1585655378001-337.png]]
392
393 Figure: Range of available thickness values for design
394
395 To run element-based design for the load combinations, select the required shell element and/or element group with the //Auto design// command and click [[image:1585655391773-363.png]] //Design// tool. The quick process results recommended thickness values and the utilization of the shell model elements. Check the //Display table// box to have a look at the overall design results (see before).
396
397 The upper table shows the design efficiency and the maximal utilization of the designed single element and groups based on the found thickness values. The bottom table displays the utilization details of the shell model element or the members of a group selected in the upper table.
398
399 (% class="table-hover" style="width:648px" %)
400 |(% style="background-color:#0076cb; width:156px" %) |(% style="background-color:#0076cb; width:489px" %)(% style="color:#ffffff" %)**Meaning**
401 |(% style="width:156px" %)[[image:1585655414208-719.png]]|(% style="width:489px" %)Suitable thickness is available
402 |(% style="width:156px" %)[[image:1585655420588-215.png]]|(% style="width:489px" %)(((
403 Suitable thickness is not available
404
405 (Modify the range of available thicknesses or steel materials.)
406 )))
407 |(% style="width:156px" %)Group|(% style="width:489px" %)ID of a single element or a group name
408 |(% style="width:156px" %)Design parameters|(% style="width:489px" %)The defined range of available thicknesses
409 |(% style="width:156px" %)Applied thicknesses|(% style="width:489px" %)Thickness currently assigned to the shells
410 |(% style="width:156px" %)Max|(% style="width:489px" %)Max. utilization of a model element or the significant member of a group
411 |(% style="width:156px" %)Min|(% style="width:489px" %)Max. utilization of the less significant group member
412 |(% style="width:156px" %)Bar|(% style="width:489px" %)ID of the designed single bar or a group member
413 |(% style="width:156px" %)Stress|(% style="width:489px" %)Stress utilization
414 |(% style="width:156px" %)FBS|(% style="width:489px" %)Utilization for flexural buckling around the stiff axis
415 |(% style="width:156px" %)FBW|(% style="width:489px" %)Utilization for flexural buckling around the weak axis
416 |(% style="width:156px" %)TB|(% style="width:489px" %)Utilization for torsional buckling
417 |(% style="width:156px" %)LTB|(% style="width:489px" %)Utilization for lateral torsional buckling
418 |(% style="width:156px" %)LB|(% style="width:489px" %)Utilization for local buckling
419
420 Table: The meaning of symbols and utilization results
421
422 Quick redesign can be done inside the //Utilization// table:
423
424 1. Select a bar or a design group in the upper table.
425 1. Modify the range of available plate thicknesses for the select element under //Parameters//.
426 1. Click //Design//.
427
428 == Manual Design ==
429
430 |[[image:1585655460640-282.png]]|With //Manual design// quick utilization check can be done for custom (also different) thickness values of selected steel plates (or their groups). Just select steel plate(s) and set a thickness value in the appeared dialog. Run //Check// calculation to run and display utilization check for the modified plates according to their new thickness values.
431
432 |(% style="width:109px" %)[[image:warning.png]]|(% style="width:1381px" %)The meaning of the utilization components, the table content and features are the same as written before at //Auto design//.
433
434 [[image:1585655503440-284.png]]
435
436 Figure: Quick check by Manual design
437
438 == Detailed Result ==
439
440 Utilization of steel bar-shell models can be displayed in the following cases:
441
442 * After global //Auto design//, you can display utilization of all steel shell models.
443 * When running element-based //Auto design//, utilization can be displayed by designed elements.
444 * After //Manual design//, element-based //Check// displays utilization for selected elements.
445 * After global //Check// done for all bar-shell elements having final plate thicknesses.
446
447 |(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**No.**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Global Auto design**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Element-based Auto des.**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Element-based Check**|(% style="background-color:#0076cb" %)(% style="color:#ffffff" %)**Global Check**
448 |1|[[image:1585655544674-590.png]] //Calculate > Design calculation > Auto design all structural elements//|[[image:1585655610365-993.png]] //Auto design//|(((
449 [[image:1585655611866-505.png]] //Auto design// and/or
450
451 [[image:1585655620960-324.png]] //Manual design//
452 )))|(((
453 [[image:1585655613472-125.png]] //Auto design// and/or
454
455 [[image:1585655622549-398.png]] //Manual design//
456 )))
457 |2|(((
458 [[image:1585655592310-385.png]] //New result > Steel bar, shell model//
459 )))|(((
460 [[image:1585655594347-587.png]] //New result > Steel bar, shell model//
461 )))|[[image:1585655628046-475.png]] //Check//|[[image:1585655604500-868.png]] Apply changes
462 |3| | |(((
463 [[image:1585655596493-206.png]] //New result > Steel bar, shell model//
464 )))|[[image:1585655548438-395.png]] //Calculate > Design calculation > Auto design all structural elements//
465 |4| | | |(((
466 [[image:1585655598308-419.png]] //New result > Steel bar, shell model//
467 )))
468
469 Table: Steps of displaying steel bar-shell model utilization by different design cases
470
471 |[[image:1585655641962-654.png]]|Utilization displayed with //New result// appears for all designed bar-shell models. The utilization components for an element/design group can be displayed with //Detailed result//.
472
473 //Detailed result// opens two new windows in the current project after selecting a shell model or group member, which display:
474
475 * **Applied shell thicknesses **(//Detailed result// window)
476 A list displays the applied thicknesses by the steel plate components.
477 * **Detailed calculation formulas **(//Detailed result// window)
478 Calculation details and final values are collected by checking types: //Stresses//, //Flexural buckling, stiff/weak direction//, //Torsional buckling//, //Lateral torsional buckling //and //Local buckling//. The proper results are displayed in green, while the red result warnings you to repeat design with new thickness values. The content of the utilization checks depends on (% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)//Display options//(%%) and //Buckling mode// (see later). Not relevant checks can also be hidden.
479 \\[[image:1585655677097-404.png]]
480 \\Figure: Utilization checks and formulas
481 * **Summary graph **(//Detailed result// window)
482 //Summary// graph is displayed with legend by default.
483 [[image:1585655698189-890.png]]
484 Figure: Utilization summary
485 * **Buckling mode** (//Buckling mode// window)
486 Based on stability analysis, the calculated shapes of the bar-shell model can be displayed in 3D view. Just select the required shape from the //Shape// drop-down list of the navigator panel and the program automatically shows the deformed shape in the current //display mode//. //Buckling mode// can be also chosen for the selected shape that affects on the design check content of the //Detailed result// window. You can add numeric values to the deformed shape or run buckling animation.
487 [[image:1585655719486-312.png]]
488 Figure: Buckling shape
489
490 [[image:1585655744718-515.png]]// Tabmenu// contains the following tools and settings for the //Detailed result// window:
491
492 * **Selection of element to display**
493 You can choose a unique or a design group member from the drop-down lists to display its detailed results mentioned before. Each row displays the ID and the maximum utilization of a member. In case of a design group, “Maximum” means the significant member having the maximum utilization.
494 * **Selection of design load**
495 A load combination can be selected for detailed results. Each row displays the name of the available load combination and its utilization effect. “Maximum” means the significant load combination.
496 * (((
497 [[image:1585655784875-736.png]] **Auto design**
498 Quick //Auto design// can be done for the currently displayed unique/group member. Set the thickness of the steel plate components, and then click //OK// to start design that updates all detailed result figures and tables.
499 )))
500 * (((
501 [[image:1585655808924-391.png]]** Display options**
502 The content and the appearance of the detailed result can be set with //Display options//.
503 )))
504 * (((
505 [[image:1585655816765-192.png]]** Go to**
506 Navigate in the //Detailed result// window by selecting the required design type in the drop-down list. It is useful when you are in zoomed view.
507 )))
508
509 [[image:1585655826034-120.png]] Click //Tools > Add view to document// to place all calculation and check formulas into [[(% class="wikiinternallink" %)//Documentation//>>path:/xwiki/wiki/femdesignwiki/get/Manuals/User%20Manual/Steel%20Design/?sheet=CKEditor.ResourceDispatcher&outputSyntax=plain&language=en&type=doc&reference=Manuals.User+Manual.Documentation.WebHome&typed=true]](%%).
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