{"id":2944,"date":"2018-06-29T07:22:35","date_gmt":"2018-06-29T07:22:35","guid":{"rendered":"http:\/\/buildsoftsupport.com\/?post_type=ht_kb&#038;p=2944"},"modified":"2023-08-25T08:52:23","modified_gmt":"2023-08-25T08:52:23","slug":"how-do-rotated-supports-work","status":"publish","type":"ht_kb","link":"https:\/\/support.buildsoft.eu\/es\/knowledge-base\/how-do-rotated-supports-work\/","title":{"rendered":"How do rotated supports work"},"content":{"rendered":"<div>If you rotate a support, it can only take reaction\u00a0<strong>in <span style=\"text-decoration: underline;\">the direction of the rotation<\/span><\/strong>.<\/div>\n<div>So if you rotate for example a support in the Y direction (= left support in the image) over an angle of \u03b1\u00a0\u00a0\u21bb in the XY plane, it means that<\/div>\n<div>\n<ul>\n<li>the resulting reaction forces (R<sub>X<\/sub>\u00a0and\u00a0R<sub>Y<\/sub>) in Y and X direction are related.<br \/>\nR<sub>X<\/sub> = R * sin (\u03b1)<br \/>\nR<sub>Y<\/sub> = R * cos (\u03b1)<img decoding=\"async\" loading=\"lazy\" class=\"wp-image-2967 size-medium aligncenter\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports9-300x114.jpg\" alt=\"\" width=\"300\" height=\"114\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports9-300x114.jpg 300w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports9-50x19.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports9-60x23.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports9-35x13.jpg 35w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports9.jpg 624w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/>Otherwise, the resulting vector for the reaction can never have the same angle \u03b1 as the support.<\/li>\n<li>the rotated Y support <strong>can not be seen as a combination of a support in the Y and X-direction (although that is what you would expect)<\/strong>. Because in the latter case, there is no correlation between the magnitude of the reactions in Y and X direction (while that is the case in a rotated support).<\/li>\n<\/ul>\n<p><img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-2945 size-medium\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports-300x50.jpg\" alt=\"\" width=\"300\" height=\"50\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports-300x50.jpg 300w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports-768x128.jpg 768w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports-50x8.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports-60x10.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports-35x6.jpg 35w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports.jpg 793w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/p>\n<ul>\n<li>Finding equilibrium with rotated supports is not guaranteed.<\/li>\n<\/ul>\n<p>An example:<\/p>\n<ol>\n<li>Consider a beam loaded in the middle with a point load Q. The boundary conditions are:\n<ul>\n<li>In A: support in Y direction, rotated 45\u00b0 \u21bb<\/li>\n<li>In B: support in Y direction, not rotated<br \/>\n<img decoding=\"async\" loading=\"lazy\" class=\"size-full wp-image-2946 aligncenter\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports2.jpg\" alt=\"\" width=\"287\" height=\"261\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports2.jpg 287w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports2-50x45.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports2-60x55.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports2-35x32.jpg 35w\" sizes=\"(max-width: 287px) 100vw, 287px\" \/><\/li>\n<\/ul>\n<\/li>\n<li>The load Q can be split into two components Q<sub>X<\/sub> and Q<sub>Y<\/sub>.<img decoding=\"async\" loading=\"lazy\" class=\"size-large wp-image-2947 aligncenter\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports3.jpg\" alt=\"\" width=\"293\" height=\"265\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports3.jpg 293w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports3-50x45.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports3-60x54.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports3-35x32.jpg 35w\" sizes=\"(max-width: 293px) 100vw, 293px\" \/><\/li>\n<li>The horizontal load\u00a0Q<sub>X<\/sub> must be beared by support A, resulting in a reaction R<sub>A.X<\/sub>.<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-2948 size-full\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports4.jpg\" alt=\"\" width=\"294\" height=\"265\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports4.jpg 294w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports4-50x45.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports4-60x54.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports4-35x32.jpg 35w\" sizes=\"(max-width: 294px) 100vw, 294px\" \/><\/li>\n<li>Since support A can only bear forces in this\u00a0<img decoding=\"async\" loading=\"lazy\" class=\"img_inline alignnone size-full wp-image-2950\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports6.jpg\" alt=\"\" width=\"41\" height=\"47\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports6.jpg 41w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports6-31x35.jpg 31w\" sizes=\"(max-width: 41px) 100vw, 41px\" \/> direction, also the vertical component of the load\u00a0Q<sub>Y<\/sub> must be beared by support A.<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-2949 size-full\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports5.jpg\" alt=\"\" width=\"284\" height=\"274\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports5.jpg 284w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports5-50x48.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports5-60x58.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports5-35x35.jpg 35w\" sizes=\"(max-width: 284px) 100vw, 284px\" \/><\/li>\n<li>Since\u00a0R<sub>A.X<\/sub> = Q<sub>X<\/sub> and R<sub>A.Y<\/sub> = Q<sub>Y<\/sub>, it follows that R<sub>A<\/sub>\u00a0= Q. Translational equilibrium is met. Now let&#8217;s write a rotational equilibrium around point A: Q * 0.5* L = 0<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-2958 size-medium\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Support8-300x252.jpg\" alt=\"\" width=\"300\" height=\"252\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Support8-300x252.jpg 300w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Support8-50x42.jpg 50w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Support8-60x50.jpg 60w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Support8-35x29.jpg 35w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Support8.jpg 505w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/>Conclusions:\n<ul>\n<li>With the current boundary conditions no rotational equilibrium can be found.<\/li>\n<li>You&#8217;ll get the message in Diamonds: equilibrium issues in the following direction(s): X; Y.<sup><a id=\"ref*\" href=\"#fn*\">*<\/a><\/sup><\/li>\n<\/ul>\n<\/li>\n<li>It would be a different story when point A would be a support in the Y and X-direction. Then support A would take the horizontal force\u00a0Q<sub>X<\/sub> and support B the vertical force Q<sub>Y<\/sub>. There would be no vertical reaction in support A (R<sub>A.Y<\/sub>=0). The rotational\u00a0equilibrium would be met.<img decoding=\"async\" loading=\"lazy\" class=\"aligncenter wp-image-2952 size-full\" src=\"http:\/\/buildsoftsupport.com\/wp-content\/uploads\/2018\/06\/Supports7.jpg\" alt=\"\" width=\"273\" height=\"286\" srcset=\"https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports7.jpg 273w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports7-48x50.jpg 48w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports7-57x60.jpg 57w, https:\/\/support.buildsoft.eu\/wp-content\/uploads\/2018\/06\/Supports7-33x35.jpg 33w\" sizes=\"(max-width: 273px) 100vw, 273px\" \/><\/li>\n<\/ol>\n<\/div>\n<p><sup id=\"fn*\">*\u00a0The message on equilibrium issues can also have other causes. If your model didn&#8217;t contain rotated supports, please send your model (*.bsf-file) to the support desk (support@buildsoft.eu)\u00a0<a title=\"Jump back to footnote * in the text.\" href=\"#ref*\">\u21a9<\/a><\/sup><\/p>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If you rotate a support, it can only take reaction\u00a0in the direction of the rotation. So if you rotate for example a support in the Y direction (= left support in the image) over an angle of \u03b1\u00a0\u00a0\u21bb in the XY plane, it means that the resulting reaction forces (RX\u00a0and\u00a0RY)&#8230;<\/p>\n","protected":false},"author":3,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":[],"ht-kb-category":[59],"ht-kb-tag":[715,714,716],"_links":{"self":[{"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb\/2944"}],"collection":[{"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb"}],"about":[{"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/types\/ht_kb"}],"author":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/comments?post=2944"}],"version-history":[{"count":4,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb\/2944\/revisions"}],"predecessor-version":[{"id":10038,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb\/2944\/revisions\/10038"}],"wp:attachment":[{"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/media?parent=2944"}],"wp:term":[{"taxonomy":"ht_kb_category","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb-category?post=2944"},{"taxonomy":"ht_kb_tag","embeddable":true,"href":"https:\/\/support.buildsoft.eu\/es\/wp-json\/wp\/v2\/ht-kb-tag?post=2944"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}