Render error aboutdeformable body

I build a deformable body, but the concept view is different from real view.


the blue geometry is concept body which correspond to the deformable behavior. But the red geometry is real body, it penetrates the box.

Moreover, dose someone know how to make deformable more rigid? I set the young’s modulus very big (about 10^12). The body is also very soft like 10^7. But small young’s modulus (like 10^3) lead to significant change.