Easy Fastener... Beam?

[kspea]

I am looking for a quick way to verify bolt shear and tensionfor bolts used to fastenbrackets to a base. I am also performing hand calculations but I want a check.


My model consists of a base part and a bracket. the base part is simplified and usedfor contact. To simplify it would be like an "L" shaped braket bolted to a base on the bottom of the "L" and then a force applied to the top of the "L" which pryes the bracket offthe base. The result is bolts in tension and shear.


I have tried the fasteners but they do not return tension unless preload is used and I have not had good results using the preload option.


My thought was to use a beam to connect the bracket to the base at the bolt location and then I could get the reactions at the beam ends. But I get constraint errors. I have also tried springs with errors as well. Any thoughts on how to get this to work or any other suggested methods?

 

[Luis Aguirre]

kspea,


What you need to do is create points at the center of each part bolt hole. Connect each point with a spring element to simulate the bolt and assign a very high stiffness to the spring. Used rigid connection to connect the center points to the bolt holes ( if using shells use the endge of the bolt hole, for solids assign the the rigid links to the inside surface of the bolt hole). Now create measure for each of the spring and request x, y and z components. If x is the axial direction of the bolt this should give you tension of the bolt if the number is possitive. For shear use (y^2+z^2)^0.5 results.





Luis