How the stresses are recovered to nodes from reduced integration? Element quad4, one gauss point in the center of element.
They’re extrapolated according to the element shape function and then averaged to give a single value. The same procedure is used for fully-integrated elements.
For an element with one integration point the stresses at the nodes and integration points are the same. These elements are sometimes called constant stress/strain elements. Nodal values may still get averaged to produce a single value though.
Above is a snippet.