Hello,
I am a civil engineer student and I have some questions about software.
I want to evaluate displacement in a shallow foundation. In my case the structure is modeled as a rigid element without own weight. I give it next properties:



Here is my complete model:



And here are the vertical displacements that software give me.



My objective is to determine total displacement in foundation but the problem is that in my output I don't have foundation’s displacement.
So, what could be my error in inputs? Maybe my interpretation of output is wrong.
I hope you can help me in this matter.
Thanks.

couple of points:

1 - ADONIS is based on explicit finite element and uses time marching method with small time step to solve the problems which means even for static analysis you need to specify density for the materials and using near zero density means no displacement. there are tones of publications on explicit finite element out there that you might find useful.

2- using super large stiffness in the model will cause the time step to be very very small and it takes forever for model to converge so I recommend you to use reasonably large enough value (two or three order of magnitude larger) to maintain relative rigidity not absolute.

3- if you are looking for displacement due to force only I recommend you to remove the gravity and purely look at the displacement caused by applied forces.

I modified your file and created new file which is attached here. please go though the changes and let me know if you need further information. by the way for your foundation I assumed density of concrete and as you can see stiffness is large enough to provide relative rigidity.

couple of points:

1 - ADONIS is based on explicit finite element and uses time marching method with small time step to solve the problems which means even for static analysis you need to specify density for the materials and using near zero density means no displacement. there are tones of publications on explicit finite element out there that you might find useful.

2- using super large stiffness in the model will cause the time step to be very very small and it takes forever for model to converge so I recommend you to use reasonably large enough value (two or three order of magnitude larger) to maintain relative rigidity not absolute.

3- if you are looking for displacement due to force only I recommend you to remove the gravity and purely look at the displacement caused by applied forces.

I modified your file and created new file which is attached here. please go though the changes and let me know if you need further information. by the way for your foundation I assumed density of concrete and as you can see stiffness is large enough to provide relative rigidity.

In my case, I must to consider gravity because I must to consider soil weight. The problem is when there is gravity also there is a vertical force in my foundation and I need specifically a net force of 7000 kN.

To calculate vertical force due to mass of the structure I need the length of the foundation in “k”direction because this way I can calculate its volume and its weight and I can know what is the vertical force that I need on top of the structure.

Next figure shows the situation:



Thank you so much for your help.