Quadrilaterals

    (syntax)

NINTEG

nxi and neta respectively are the number of integration points n in the isoparametric  direction, and n in the isoparametric  direction of the element. See §21.5.3.1 for enumeration and location of the integration points.

Stabilization.

For 1-point integration of linear quadrilaterals, DIANA applies a stabilization procedure to avoid zero-energy modes. The procedure relies on the addition of a small least squares contribution to the element energy norm, see Roddeman [12]. The default value for  in this procedure is 10^-8 . [  = 10^-8 ] You may overrule this default via the following special input data.

    (syntax)

STBFAC

eps overrules the default value for  .