How good are you with a Real history? Here are the parameters for the weld challenge. Two variable amplitude load levels, using the grapple skidder torque history will have been run by the time of the next meeting. First test: Peak load = 6106 lbs ( = 19.2 times the loads in load file ) We have at least two tests done. Second test: Peak load = 8618 lbs ( = 27.1 times the loads in the file ) Pete and I (John Bonnen) hope to have two tests (his will probably be done -- I'm not sure my test frame can stand the 8618lb max loads. The brace broke near the end of the last test.) Load history location: http://fde.uwaterloo.ca/Fde/Weld2/grpltorWeld.html Details and a brief discussion showing the test piece fixturing (contraint) during testing can be found at http://fde.uwaterloo.ca/Fde/Weld2/testgeom.html Incidentally, calibrating the "model" that you have to the previous results from Weld Challenge 1 is considered poor sportsmanship. One should make predictions without consideration of the error between one's prediction and previous results. Thanks, John J. Bonnen mailing: Ford Motor Co.
Note that the original stress-strain life crack initiation data file used by many of the simulators is not available. The files indicated below are felt to be reasonably similar. Crack Initiation: Strain controlled ASTM E606 axial specimen test results for ASTM A36 steel can be found here Note that these are not tests from the same tube material, but were collected from other studies. Crack propagation The da/dN vs ΔK data for A36 steel was not available during the original tests and simulations, but became available later. It was collected from presentations and papers (Refs.: [1-4]) and is plotted in figure 2.
Fig. 2 : Collected A36 and similar low carbon steel da/dN vs ΔK data.
Notes on section properties available
(Click figure to enlarge)
Fig. 4 : Section properties
The load history file is located here:
Fig. 6: Grapple Skidder torsion history
When one runs a "hilo" on the history file the extrema are:
hilo2 Starts. Usage: hilo2
out #The 1st data line has 1 columns of numbers #Done. Scanned 5728 data lines. #Total lines= 5750 #Highs: 318.00000 #Lows : -238.00000
First test: Peak load = 6106 lbs ( = 19.2 x values in the history file ) Second test: Peak load = 8618 lbs ( = 27.1 x values in the history file )
(1 Block = 2864 cycles) Test Lab. Load Pk. No Crack 30mm Crack Final Crack Location lbs blocks blocks (blocks : mm) ------------ -------- -------- ---------- ---------- -------------- Ford Research +6106 1750 " 8618 U. of Illinois " 2181 Partial penetration " 10962 Ford Research +8618 450 Partial penetration " 1850 U. of Illinois " not obsv. Partial penetration " 1505( Click figure to enlarge }
Further information on the testing and results can be found here: