Learning Forum

[Theogene]

 

I am modeling a prestressed concrete sleeper under impact. One was telling me to draw a impactor object in contact with the sleeper. do i have to apply additional load, or the weight of the impactor will play a role of the creating an impact load at the contact area, if yes how big will be my impactor object to be? Thanks for your help.

 

[peteroznewman]

 Theogene, you could ask this follow-up question in the same discussion as your original question, instead of creating this new discussion.

The impactor has mass, stiffness, velocity and has a shape at the contact point. These inputs completely define the impact load. You can also turn on gravity, but no additional load is required.

It's your model, you decide how big to make the impactor, unless there is some Standard for testing prestressed concrete sleepers under impact.

You could replace the impactor with a force-time history profile on a specified area of the sleeper. That would take much less time to compute, but the force profile is more abstract than the physically meaningful mass and velocity of an object actually impacting the sleeper.

[Theogene]

Thanks sir.

i tried as you have proposed.

the only challenge i am having now is that when i run the model, the maximum deflection is found on impactor not on the sleeper.

The following figure shows that the maximum deflection is located to the impactor and for sleeper, the deflection is zero.

Sir, could you guide me please?