{"id":4500,"date":"2019-07-12T13:44:22","date_gmt":"2019-07-12T13:44:22","guid":{"rendered":"http:\/\/buildsoftsupport.com\/?post_type=ht_kb&#038;p=4500"},"modified":"2026-04-09T15:13:41","modified_gmt":"2026-04-09T15:13:41","slug":"how-to-do-a-seismic-analysis","status":"publish","type":"ht_kb","link":"https:\/\/support.buildsoft.eu\/nl\/knowledge-base\/how-to-do-a-seismic-analysis\/","title":{"rendered":"How to do a seismic analysis"},"content":{"rendered":"    \t\t<div class=\"hts-messages hts-messages--info   hts-messages--withicon \" id=\"\" style=\"\">\r\n    \t\t\t    \t\t\t    \t\t\t\t<p>\r\n    \t\t\t\t\t\n<ul>\n<li>A seismic analysis requires the license <em>Seismic Analysis.<\/em><\/li>\n<li>The seismic analysis in Diamonds\/ PowerFrame uses multi-modal-analysis. Other types of seismic analysis are not available with the BuildSoft software.<\/li>\n<\/ul>\n    \t\t\t\t<\/p>\r\n    \t\t\t    \t\t\t\r\n    \t\t<\/div><!-- \/.ht-shortcodes-messages -->\r\n    \t\t\n<ol>\n<li>Enter the geometry of the structure as you would normally do.<br \/>\nIf your model contains multiple independent structures, make one Diamonds-file for each structure.<\/li>\n<li>Load group and masses\n<ul>\n<li>Click on\u00a0<img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-1442\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2017\/08\/KnopLastengroepen.png\" alt=\"\" width=\"34\" height=\"33\" \/>. Add a load group and select &#8216;Seismic&#8217; from the list.<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-5800 size-full\" src=\"https:\/\/buildsoftsupport.com\/wp-content\/uploads\/2019\/07\/SeismicDesign1.png\" alt=\"\" width=\"985\" height=\"421\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1.png 985w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1-300x128.png 300w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1-768x328.png 768w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1-50x21.png 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1-60x26.png 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign1-35x15.png 35w\" sizes=\"(max-width: 985px) 100vw, 985px\" \/><\/li>\n<li>To calculate the response of the structure due to the seismic load, the modal parameters of the structure (eigen modes and -frequencies) must be calculated by Diamonds. These model parameters depend on the stiffness and mass distribution of the structure.\n<ul>\n<li>The stiffness is known by Diamonds. It is in the geometry of the structure.<\/li>\n<li>The mass distibution is related to the vertical loads (point loads, line loads, surface loads) (0,981kN -&gt; 100kg).<br \/>\nThe correlation coefficient \u03c6 multiplied by the combination factor \u03a8<sub>2<\/sub>\u00a0(for Eurocode and Eurocode-like standards) will determine the masses.<br \/>\nFor example: a life load of 5kN\/m will lead to 5kN\/m\u00b2\u00a0 x\u00a0\u00a0\u03a8<sub>2\u00a0<\/sub> x\u00a0\u03c6 =\u00a05kN\/m\u00a0 x\u00a0\u00a00,3<sub>\u00a0<\/sub>\u00a0x\u00a01 = 1,5kN\/m of mass to be taken into account during the model analysis.<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-5799 size-full\" src=\"https:\/\/buildsoftsupport.com\/wp-content\/uploads\/2019\/07\/SeismicDesign2.png\" alt=\"\" width=\"985\" height=\"421\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2.png 985w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2-300x128.png 300w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2-768x328.png 768w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2-50x21.png 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2-60x26.png 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2019\/07\/SeismicDesign2-35x15.png 35w\" sizes=\"(max-width: 985px) 100vw, 985px\" \/><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<li>Define the seismic\u00a0spectrum: select the load group Seismic from the pull down list and click on\u00a0<img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-4538\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2019\/07\/KnopSeismisch.png\" alt=\"\" width=\"35\" height=\"35\" \/>. Enter the desired parameters.<br \/>\nRead <a href=\"http:\/\/buildsoftsupport.com\/knowledge-base\/how-to-introduce-a-user-defined-seismic-spectrum\/\">here <\/a>how to define a user defined seismic spectrum.<\/li>\n<li>Generate the combinations\u00a0<img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-3860\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2019\/01\/ButtonCombinations.jpg\" alt=\"\" width=\"35\" height=\"35\" \/>. Don&#8217;t forget to\u00a0check the ULS SC combinations.<\/li>\n<li>Run the analysis\u00a0<img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-1292\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2017\/06\/KnopRekenmachine.png\" alt=\"\" width=\"29\" height=\"29\" \/>.<br \/>\nThe content of the tab page &#8216;Dynamic&#8217; is the same as for <a href=\"https:\/\/support.buildsoft.eu\/knowledge-base\/how-to-do-a-modal-analysis\/\">a model analysis.<\/a><br \/>\nIf your model contains non-linear behaviour, you&#8217;ll have to choose a reference combination (usually\u00a0 ULS FC is taken).<\/li>\n<li>Verify if the mass participation in each direction is at least 90% (source: EN 1998-1 \u00a74.3.3.3.1 (3)). You can see the mass participation in the <a href=\"https:\/\/support.buildsoft.eu\/docs\/diamonds\/results-buttons\/tables\/table-modal-information\/\">table &#8220;Modal information&#8221;<\/a> <img decoding=\"async\" loading=\"lazy\" class=\"alignnone size-full wp-image-10066\" src=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2023\/09\/KnopModaleInformatie.png\" alt=\"\" width=\"19\" height=\"19\" \/> (expressed in %).<br \/>\nWhen you don&#8217;t reach 90%, you can either ask more eigen modes in the modal analysis (see Step 5 above) or check the option &#8220;Apply quasi static correction&#8221;. A combination of both is also possible.<br \/>\nNote: if the seismic spectrum is only defined for the horizontal directions, the mass participation in the vertical Y-direction is irrelevant.<\/li>\n<li>Run the reinforcement calculation <img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-3859\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2019\/01\/ButtonReinforcement.jpg\" alt=\"\" width=\"23\" height=\"23\" \/>, steel or timber design <img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-3446\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/08\/ButtonSteelVerificationTimberVerification.jpg\" alt=\"\" width=\"26\" height=\"26\" \/>.<br \/>\nDiamonds will take the seismic combinations ULS SC into account.<\/li>\n<li>Verify the deformations.<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Enter the geometry of the structure as you would normally do. If your model contains multiple independent structures, make one Diamonds-file for each structure. Load group and masses Click on\u00a0. Add a load group and select &#8216;Seismic&#8217; from the list. To calculate the response of the structure due to the&#8230;<\/p>\n","protected":false},"author":3,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":[],"ht-kb-category":[1271],"ht-kb-tag":[198,1176,619,620,621,212,196,1178,197,1177,213],"_links":{"self":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/4500"}],"collection":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb"}],"about":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/types\/ht_kb"}],"author":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/comments?post=4500"}],"version-history":[{"count":2,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/4500\/revisions"}],"predecessor-version":[{"id":28569,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb\/4500\/revisions\/28569"}],"wp:attachment":[{"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/media?parent=4500"}],"wp:term":[{"taxonomy":"ht_kb_category","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb-category?post=4500"},{"taxonomy":"ht_kb_tag","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/nl\/wp-json\/wp\/v2\/ht-kb-tag?post=4500"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}