https://forums.autodesk.com/t5/robot-structural-analysis-forum/section-definition-weighted-properties-formula/m-p/9152137#M22024 <P>Hi&nbsp;@Anonymous&nbsp;</P> <P>&nbsp;</P> <P>"Alpha-i" are section/contour material property. For most coefficients(Ax, Iy, Iz) Young modulus is used.</P> <P>&nbsp;</P> <P>If I managed to answer your question(s) press the Accept as Solution button please. This will help other users to find solution(s) much faster. Thank you.</P> Mon, 18 Nov 2019 08:59:01 GMT Krzysztof_Wasik 2019-11-18T08:59:01Z https://forums.autodesk.com/t5/robot-structural-analysis-forum/section-definition-weighted-properties-formula/m-p/9149467#M22023 <P>Hello everyone,</P><P>&nbsp;</P><P>I don't understand how the weighted properties of a composite material are calculated in the section définition tool. The help (<A href="https://help.autodesk.com/view/RSAPRO/2019/ENU/?guid=GUID-3C08787E-34CE-4FB0-B0B0-DFDC50EA9E8E" target="_blank" rel="noopener">https://help.autodesk.com/view/RSAPRO/2019/ENU/?guid=GUID-3C08787E-34CE-4FB0-B0B0-DFDC50EA9E8E</A>&nbsp;) gives the following formula for a weighted property A* :</P><P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="image.png" style="width: 367px;"><img src="https://forums.autodesk.com/t5/image/serverpage/image-id/698397iCA7DBD44EB0A788E/image-size/large?v=v2&amp;px=999" role="button" title="image.png" alt="image.png" /></span></P><P>What is "a" (or "alpha" ?) ?</P><P>&nbsp;</P><P>Plus, I have two materials side to side, and not a fiber reinforced material for example. Is it OK to use the properties given by the section definition tool, assuming the larger material as the "base" ?</P><P>(This second question may be answered with the first one)</P><P>&nbsp;</P><P>Best regards,</P><P>François</P> Fri, 15 Nov 2019 17:05:25 GMT https://forums.autodesk.com/t5/robot-structural-analysis-forum/section-definition-weighted-properties-formula/m-p/9149467#M22023 Anonymous 2019-11-15T17:05:25Z https://forums.autodesk.com/t5/robot-structural-analysis-forum/section-definition-weighted-properties-formula/m-p/9152137#M22024 <P>Hi&nbsp;@Anonymous&nbsp;</P> <P>&nbsp;</P> <P>"Alpha-i" are section/contour material property. For most coefficients(Ax, Iy, Iz) Young modulus is used.</P> <P>&nbsp;</P> <P>If I managed to answer your question(s) press the Accept as Solution button please. This will help other users to find solution(s) much faster. Thank you.</P> Mon, 18 Nov 2019 08:59:01 GMT https://forums.autodesk.com/t5/robot-structural-analysis-forum/section-definition-weighted-properties-formula/m-p/9152137#M22024 Krzysztof_Wasik 2019-11-18T08:59:01Z