question regarding new components - finite elements and units

Daniel,

   First off the new tools are remarkable and as always are so empowering to use. I never thought I would be able to calculate and consider projects to this degree without much engineering know how. Thanks for that. Now I do have some questions. 

1. I am using the area weight tool. I am first calculating the volume of the form. I then multiply that value by it's density. So for concrete I am using 2400 kg/m^3 x volume. I then divided that number by the area of the membrane that is supporting the mass. This gives me my area weight. It seems to be working well but I want to verify that this is the correct workflow. I also want to verify that gravity would be turned off since I am thinking it is already calculated within the weight component. 

2. I am finding that the new triangular element tool works much better than trying to use EA/L as input for the springs from mesh. Even when I set the timestep, subiteration, and drag I still have issues with getting very stiff materials to work. On the new finite elements tool I wanted to verify that  E was in pascals. I also wanted to ask if I use imperial units can psi be entered. Now from what I am seeing the materials are deforming more than expected and to get less deformation and stretch in the mesh area I am finding the E value needs to be increased more than the true material values. Often I am raising E by a multiple of 10 or 100. 

I am going to describe my problem and I will gladly share the definition if you'd prefer looking it over but basically I have an inflated membrane at a certain pressure made of a particular material. I then have a certain volume of concrete on top of the inflated membrane. My goal is to review the displacements as the concrete is applied over the membrane and find the proper pressures to apply to keep it free from deformation.  I am including a picture from a project that we used kangaroo on and attempted to deal with such issues. It was a class sponsored by Cloud9 architecture held at Art Center College of Design where I was one of the instructors. Hopefully this illustrates the problem. To summarize any example file that shows the best way to implement real material properties and unit based forces would be a helpful reference and would be greatly appreciated.