Three point Bending
I want to do a linear simulation of a three point bending test of a sandwich panel.
According to C393 ASTM norm, the test specimens must have a length of L=200mm and a width of b=75mm.
The specimens are supported on two roller bars under them, which shall allow free rotation and would have a midspan distance from each other of S=150 mm. The load force should be applied by another roller bar positioned in the middle of the specimens on the top of them.
A pressure pad of length l=25mm and throughout the width of the panel: b=75mm , should be positioned between the specimens and the loading bar in order to prevent local damage of the facing.
I try simulating the experiment by applying a force in a middle area of the upper facing with a geometry of lxb=25x75 mm^2 , in accordance to the contact area of the upper pressure pad used for the loading.
My question is how can I best simulate the simply supported area of the contact between the supporting roller bars and the sandwich panel, since the simply supported feature of ansys is only applicable on points or edges..?
By creating two lines accordingly at the center of the supposed roller bars and choosing a midspan distance 150 mm between them in spaceclaim afterwards my results of max deformation have a differnce of more than 20% lower value than the the analytical calculations.
I am using a shell solid shell model for the sandwich panel and use two bonded contacts between them where both have as a contact geometry the solid.
From my understanding the support is not completely simulated here and the line boundary condition is causing this difference.
Can you help me in how to better simulate the simply supported area between the roller pads and the panel, while staying in the linear analysis and not using two other bodies for the under roller pads?
Thank you in advance!