Guys, thank you for your prompt replies.
The company I work for doesn't have nCode or Fe-Safe licenses, then we have to get by on our own.
Yes, I'm interested in determining the fatigue life of the flange only, not the bolts. I took a training on nCode almost ten years ago and I vaguely...
Hi everyone!
I'm trying to run a high cycle fatigue analysis of a bolted flange submitted to bolt preload and a bending moment varying harmonically. The objective is to analyze only the flange, not the bolts.
The first load step is the preload and the second is the application of a bending...
Hi everyone
I've been trying to understand a little of the mathematics behind FEM and I got stuck in the definition of the weak (or variational) form. All literatures I have researched so far, they just say that we should multiply the differential equation by a trial function w, integrate over...
Dear Agent666
See the bolted connection in the figure attached. FB is the axial working load and "a" is the substitutional line of action of the axial working load. This strategy is applied to any kind of bolted...
Hi everyone!
VDI 2230 states that there are two kinds of loading joints: concentric and eccentric. For the case of eccentric loading joints, the variable "a" (the substitutional line of action of the axial working load) must be determined. According to section 5.2.1, the variable "a" is...
Dear RolMec, thank you for your reply.
I'm sorry, but I can stil understand why the reactive force line of action "FA" will be located, where the bending moment is zero. Is there a specific reason?
Thanks in advance.
Hi everyone!
According to VDI 2230, there are two kinds of loading joints: concentric and eccentric. For the case of eccentric loading joints, the variable "a" (the substitutional line of action of the axial working load) must be determined. According to section 5.2.1, the variable "a" is...
Hi everyone.
I got the real stress-strain curve illustrated in the attached figure for AISI 1045 steel and I need to get the data set for an elastoplastic analysis in Abaqus, i.e., I need to get the data pairs true stress-true plastic strain.
You can observe that the curve deviates from ideal...
Hi everyone!
Thank you very much for your replies. I'm sorry for taking too long to thank all of you for your comments, but I had lost my password.
mp87, you said that a tensile load can be considered as a fatigue load which brings to failure in only one cycle. So, based on your statement, do...
Hi everyone!
These days, I was reading a paper written by Prof. Norman Dowling on mean stress effect on fatigue life, whose title is “Mean Stress Effect in Stress-Life and Strain-Life Fatigue”. This paper and his book on mechanics of materials demonstrate that Goodman, Gerber and Soderberg mean...
rb1957, thank you for your prompt reply.
The way I distributed the load can be seen in the attached figure. The red lines are the rigid elements (Kincoup). And they were distributed on the area of contact with the steel cable pin. Then, the load was applied on the central node. I tried to...
Hi everyone!
I was running an elastoplastic analysis of an offshore component with three different mesh refinements in Abaqus. The attached figure illustrates the meshes and the distribution of the equivalent plastic strain (PEEQ) for each mesh. A steel cable will tied in the hole and a force...
Thank you guys for your prompt replies.
Actually, I don´t ask for stress-strain calculation in the welds, when I include them in my FEM models. But, I need to input their basic mechanical properties, like Young´s modulus and Poisson ratio. Because the welds are the strongest material of the...
Did you input Young´s modulus and Poisson ratio for the welds? If so, what were the values you inputted?
Classical literature on machine design, like Shigley, Norton and Juvinnal, say that the weld material is usually the stiffer material of the joint. Thus, in an attempt to account for this...
The offshore standard I mentioned states exactly this: "the analyst shall be warned that FEM is not good at calculation of peak stress at holes, fillets and other stress raisers (see Cook et al[]), thus the straightforward use of extreme FE-predicted stresses as hot spot stresses is discouraged...
corus and rb1957, thank you very much for your comments.
In the beginning, when I was warned that FEM was not the best tool to model stress concentration features, I thought it could be a problem of the method itself. But, the comments above helped me to understand that this "deficiency" is...
StressRook and rb1957
Thank you very much for your comments.
This issue came out when I was trying to model an offshore component with a prominent fillet radius and I was warned that FEM is not the best tool to do that. Then, I started researching why FEM would not be suited to model geometric...