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 Torsional constant J for a half round shape section Post Reply Forum
 Posted by: marrosadi ® 06/10/2004, 11:19:53 Author Profile eMail author Edit I have being searching the formula to calculate the torsional constant J for a half round section and I have not found it. Can anyone help me or tell me where can I find it? Thank you very much. ROSA

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 Re: Torsional constant J for a half round shape section Re: Torsional constant J for a half round shape section -- marrosadi Post Reply Top of thread Forum
 Posted by: phatso86 ® 08/31/2007, 10:47:09 Author Profile eMail author Edit its something u need to derive

 Re: Torsional constant J for a half round shape section Re: Torsional constant J for a half round shape section -- marrosadi Post Reply Top of thread Forum
 Posted by: acroduster1 ® 06/10/2004, 13:55:02 Author Profile eMail author Edit J for any shape is the surface integral of the density^2 over dA.  The problem is for the shape to twist on its own axis, this integral has to be taken about the centroid of the cross section.  That's where this integral gets ugly for a half-pipe shape.  You can do it by approximate methods using Excel, or just keep up your search to see if someone has listed a formula for it. If you post the dimensions of the half-pipe I can give it a go... Acro

 Correction to J formula Re: Re: Torsional constant J for a half round shape section -- acroduster1 Post Reply Top of thread Forum
 Posted by: acroduster1 ® 06/10/2004, 14:05:18 Author Profile eMail author Edit I'm sorry, it's not the density^2 over dA, it's the radius to the infinitesimal^2 integrated over dA. Integral(r^2 dA) My apologies... Acro