<
From version < 17.1 >
edited by IwonaBudny
on 2018/09/06 14:58
To version < 17.2 >
edited by IwonaBudny
on 2018/09/06 14:58
>
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... ... @@ -139,15 +139,15 @@
139 139  (% style="text-align: justify;" %)
140 140  [[image:1536237268175-179.png||height="23" width="26"]] The program contains EC8 and NS3491-12 predefined design spectra or the user can define its own spectra if necessary. The vertical spectrum is necessary when the vertical affect taken into account.
141 141  
142 +=== (% style="font-size:18px" %)**EC8 design spectrum**(%%) ===
142 142  
143 -**EC8 design spectrum**
144 -
145 145  The code gives the horizontal and vertical spectra and although the value of variables is prescribed, they can be modified if necessary.
146 146  
147 147  [[image:1536237376815-771.png||height="247" width="315"]]
148 148  
148 +**Horizontal spectra**
149 149  
150 -a. Data of horizontal design spectra:
150 +Data of horizontal design spectra:
151 151  
152 152  * Type type of spectra, which there are two in the code,
153 153  * Ground ground type, which can be A, B, C, D and E,
... ... @@ -166,13 +166,16 @@
166 166  [[image:1536237735225-141.png||height="224" width="400"]]
167 167  
168 168  (% style="text-align: justify;" %)
169 -b. The built-in vertical design spectrum is derived from the horizontal spectrum using the aυg / ag multiplicator which can be found in EC8 table 3.4 and described in 3.2.2.5(5)-(7).
169 +**Vertical spectra**
170 170  
171 171  (% style="text-align: justify;" %)
172 +The built-in vertical design spectrum is derived from the horizontal spectrum using the aυg / ag multiplicator which can be found in EC8 table 3.4 and described in 3.2.2.5(5)-(7).
173 +
174 +(% style="text-align: justify;" %)
172 172  [[image:1536237786462-739.png||height="179" width="297"]]
173 173  
174 174  
175 -c. Other input parameters (Others tab)
178 +**Other input parameters (Others tab)**
176 176  
177 177  [[image:1536237903146-157.png||height="81" width="170"]]
178 178  
... ... @@ -183,6 +183,72 @@
183 183  * qd is the displacement behavior factor, assumed equal to q unless otherwise specified.
184 184  * Foundation level when Static-linear shape is used, the program assumes that the foundation level is defined on that height. It means the pro- gram calculates the mass height from that level. In the other two calculation methods (Static-mode shape and Modal analysis) base shear force is drawn in that level and it is taken into consideration in the so called reduced mass calculation (details in Effective mass setting).
185 185  
189 +=== (% style="font-size:18px" %)**NS3491-12 design spectrum**(%%) ===
190 +
191 +**Horizontal spectra**
192 +
193 +=== [[image:1536238030672-563.png||height="220" width="281"]] ===
194 +
195 +The built-in horizontal design spectrum is based on the following formula:
196 +
197 +(% class="mark" %)S,,d,,(T,,i,,) = k,,Q,, k,,S,, γ,,1,, a,,g,, S,,e,,(T,,i,,) k,,f, spiss,,
198 +
199 +
200 +where:
201 +
202 +* Ksi(ξ) is the declining ratio for the structure, given in %. Usually 5%,
203 +* k,,Q,, is a structure factor, dependent on the type of structure,
204 +* k,,S,, is a soil factor, dependent on the type of ground,
205 +* Gamma 1(γ,,1,,) is a seismic factor, dependent on the seismic class,
206 +* a,,g,, is the maximum ground acceleration, dependent on location and reference period,
207 +* S,,e,,(T,,i,,) is the acceleration for the period Ti in the normalized response spectra, see below,
208 +* k,,f,spiss,, is a factor dependent on the reference period used.
209 +
210 +**Vertical spectra**
211 +
212 +[[image:1536238363669-269.png||height="32" width="119"]]
213 +
214 +(((
215 +(% style="text-align: justify;" %)
216 +(% class="mark" %)S,,νd,,(T,,ν,i,,) = k,,ν,, γ,,1,, a,,g,, S,,e,,(T,,ν,i,,) k,,f, spiss,,
217 +)))
218 +
219 +(% style="text-align: justify;" %)
220 +where
221 +
222 +* k,,ν,, is the ratio between horizontal and vertical response spectra, mostly set to 0,7.
223 +
224 +(% style="text-align: justify;" %)
225 +The normalized response spectrum in Norwegian code is based on four different formulas, each covering a part of the possible periods from 0 to 4 seconds. Periods over 4 seconds has to be treated in a different way anyhow, and can therefore be based on a manually written response spectrum.
226 +
227 +(% style="text-align: justify;" %)
228 +In FEM-Design, we assume, the spectrum is constant for periods over 4 seconds and equal to the value of S,,d,,(T = 4).
229 +
230 +[[image:1536238500410-574.png||height="195" width="479"]]
231 +
232 +where:
233 +
234 +* T is the vibration period,
235 +* T,,B,, = 0,1sec,
236 +* T,,C,, = 0,25sec
237 +* T,,D,, = 1,5sec
238 +* η is a factor describing how the swaying declines, calculated as: [[image:1536238569724-268.png||height="37" width="167"]]
239 +
240 +(% class="wikigeneratedid" %)
241 +**Other input parameters (Others tab)**
242 +
243 +(% class="MsoBodyText" style="margin-top:0cm; margin-right:87.25pt; margin-bottom:.0001pt; margin-left:5.5pt; text-align:justify; margin:0cm 0cm 0.0001pt 5.3pt" %)
244 +[[image:1536238618416-879.png||height="35" width="146"]]
245 +
246 +
247 +In the NS3491-12 code only foundation level should be set.
248 +
249 +=== (% style="font-size:18px" %)**Design spectra in the other national codes**(%%) ===
250 +
251 +Except for the above mentioned two codes, the user has in all cases to define the spectra in table or in a graphical way. In the Others tab only the foundation level should be set.
252 +
253 +[[image:1536238682205-293.png||height="220" width="271"]]
254 +
186 186  ----
187 187  
188 188  = 3. Calculations parameters and calculations steps =
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