


{"id":41734,"date":"2020-03-12T09:38:49","date_gmt":"2020-03-12T09:38:49","guid":{"rendered":"\/forum\/forums\/topic\/fixed-joints-instead-of-bonded-contacts-why-the-weird-similar-but-not-similar-result\/"},"modified":"2020-03-12T09:38:49","modified_gmt":"2020-03-12T09:38:49","slug":"fixed-joints-instead-of-bonded-contacts-why-the-weird-similar-but-not-similar-result","status":"closed","type":"topic","link":"https:\/\/innovationspace.ansys.com\/forum\/forums\/topic\/fixed-joints-instead-of-bonded-contacts-why-the-weird-similar-but-not-similar-result\/","title":{"rendered":"Fixed Joints instead of Bonded Contacts, why the weird (similar but not similar) result?"},"content":{"rendered":"<p>Hello everyone,<\/p>\n<p><\/p>\n<p>I am a beginner in Ansys. My problem might seem very basic, but I have not been able to find a solution in older posts, so I hope someone would be kind enough to answer my doubts.<\/p>\n<p><\/p>\n<p>I am working on a concrete gridshell structure. In my first attempt, I tried to model the connections (nodes between the different &#8220;bar\/rod elements&#8221;) of the gridshell by <strong>bonded contact <\/strong>(edge to edge). The solution for total deformation showed that the connection between one of the parts fails and &#8220;swings like a pendulum&#8221;.<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/d0389118-f8b1-4b15-941d-ab3d016b9918\/3960c9c6-64f8-4bf6-9094-ab7c009aa66a_capture1.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>However, that is not what I wanted. I want the nodes in the structure to be rigid and remain fixed. So I tried adding <strong>fixed joints<\/strong>. I was having trouble&nbsp;&#8216;automatically creating&#8217; joints (as I did for the contact elements) because in the joints tab, there is no option for edge-to-edge joints (the automatically created joints were not the edge to edge joints I wanted, but edge to face). So, after creating contacts as previously, I inserted the joints tab, but kept it empty. As can be seen from the picture below, the joints tab has &#8216;0 connections&#8217;.&nbsp;<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/d0389118-f8b1-4b15-941d-ab3d016b9918\/a2ddfd74-f84b-49b3-9a39-ab7c009c412e_capture3.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>I knew this was most probably wrong, but after the solution, I got the exact same result as before (same max\/min deformation and position), except that this time, the connection of the part did not fail. It remained intact even though it had the same deformation and same principal stresses.<\/p>\n<p><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/us.v-cdn.net\/6032193\/uploads\/attachments\/d0389118-f8b1-4b15-941d-ab3d016b9918\/0fd5b4a2-c55d-4b53-bbbe-ab7c009f28a4_capture2.jpg?width=690&amp;upscale=false\" alt=\"\"><\/p>\n<p><\/p>\n<p>I want to know whether in the second attempt, joint connections were created in my structure&nbsp;replacing the contact elements (as I wanted)? If not, then why the change in results? If yes, then why the remaining results are exactly the same as before?<\/p>\n<p><\/p>\n<p>I&nbsp;would be extremely grateful for your reply. Thank you.<\/p>\n","protected":false},"template":"","class_list":["post-41734","topic","type-topic","status-closed","hentry"],"aioseo_notices":[],"acf":[],"custom_fields":[{"0":{"_bbp_old_topic_id":["13914"],"_bbp_old_topic_author_name_id":["Anonymous"],"_bbp_old_is_topic_anonymous_id":["false"],"_bbp_old_closed_status_id":["publish"],"_bbp_author_ip":[null],"_bbp_old_sticky_status_id":["normal"],"_bbp_likes_count":["0"],"_btv_view_count":["2912"],"_bbp_subscription":["246395"],"_bbp_topic_status":["unanswered"],"_bbp_status":["publish"],"_bbp_topic_id":["41734"],"_bbp_forum_id":["27791"],"_bbp_engagement":["200","172090"],"_bbp_voice_count":["2"],"_bbp_reply_count":["7"],"_bbp_last_reply_id":["107818"],"_bbp_last_active_id":["107818"],"_bbp_last_active_time":["2020-03-13 16:38:13"]},"test":"myvue"}],"_links":{"self":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/41734","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics"}],"about":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/types\/topic"}],"version-history":[{"count":0,"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/topics\/41734\/revisions"}],"wp:attachment":[{"href":"https:\/\/innovationspace.ansys.com\/forum\/wp-json\/wp\/v2\/media?parent=41734"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}