How to export data at a specific location

[dxvn818]

Dear all,

I perform a tensile test. The "Plugin_InitSensor" exports data from the existing boundary set generated from the cooker program, such as "Boundary-xMin", "Boundary-xMax", etc. However, I want to calculate stress, strain at the section which is in the middle of beam length and perpendicular to the beam axis. That middle section will move due to the deformation of the beam in a tensile test. Could you please give me some hint to do that ?

Thank you.

Vinh

[Damien André]

Hello,

dxvn818 wrote

However, I want to calculate stress, strain at the section which is in the middle of beam length and perpendicular to the beam axis. That middle section will move due to the deformation of the beam in a tensile test.

For measuring stress, you need to create a virtual cut of your sample (as for material strength theory).
To do this, you need :
 - a SetOf that contains half of your sample
 - a sensor that measure the force acting from one part to the other part of your sample. Note that these forces are transmitted through the cohesive beams.
- Summarize these forces and divide it by the area of your sample.

For measuring strain many strategies can be applied. It depends on your real need.

To be honest, implementing such sensors are not obvious. You need a good knowledge of the GranOO programming interface.

If you need simply a tensile test, the available sensors gives you already these informations because stress & strain can be considered as homogeneous in the whole sample for 1D axial test.

Kind regards, Damien.

[dxvn818]

Hello Damien,

Yes, I have followed the procedure in "Plugin_InitBondSet" and "Plugin_InitSensor" to create a new SetOf Discrete Element and init a sensor on that set to measure the force. However, I got the resultant force equal to 0. Your answer helps me to fix it. My mistake is that I should measure the force acting on the half of the sample, while I measure the force acting at the middle section, so two forces on two sides cancelled each other which results to 0.

Thank you so much.

Kind Regards,
Vinh