|
|
||
|
|
|
|
“SFD” = shear force diagram
“BMD” = bending moment diagram
This and the next two images are from the paper:
Liu Q., Sadowski A.J. & Rotter J.M. (2018) "Ovalization restraint in four-point bending tests of tubes", Accepted for publication, ASCE Journal of Engineering Mechanics, http://dx.doi.org/10.1061/(ASCE)EM.1943-7889.0001571.
ABSTRACT: Four-point bending tests have been a staple in many structural engineering experiments as a reliable way of assessing the bending resistance of circular hollow sections, tubes and cylindrical shells, and they continue to be widely performed. However, relatively little attention appears to have been paid to quantify the effects of different boundary conditions on the test outcome. In particular, the restraint or freedom given to the cross-section at the ends of the specimen to ovalize can have a significant impact when the specimen is in an appropriate length range. Ovalization is an elastic geometrically nonlinear phenomenon that is known to reduce the elastic bending resistance by as much as half in long tubes or cylinders.
Page 344 / 444