CEL Abaqus 6.13 impact test Solid-Water-Sand

Hi to everyone ,

I am modelling an impact problem in Abaqus6.13. The problem is all about a jack-up leg impact on seabed. I have modeled a spudcan and tank setup according to the specification of a prototype which we created in our institute. According to the problem the  impact takes place under water and creates some normal force. I compared the software results and  experimental results. I came to observe a large impact force in the software results which is no way near to my experimental results. 

To model this impact problem I opted for CEL analysis in Abaqus. In a way I designed a tank and spudcan (as Rigidbody) ,Water and Sand (as uniform Eulerian parts ). I used Linear Elastic and Drucker prager plasticity feature to define sand and I used Us-Up type in EOS and dynamic viscosity to define water. In a way i should analyse the impact with different weights of the spudcan (for eg 10 15 21 kg etc ). 

What could be sensible is the damping of water should affect or resist the falling velocity of the spudcan or any body. From the ODB file i understood this effect is not taking place (for eg 10kg spudcan falls from a height of 20cm should exert an impact force of 10N-13N but i get a way too high force of 600N or so). 

What exactly I would like to extract as result is NFORC or impact force at the point of impact. 

Any Ideas about interaction between these bodies on such cases or Material parameters or elemental parameters (such as linear bulk viscosity or quadratic bulk viscosity) ??