Custom verifications

For a civil engineer, it is of primary importance to customize the checkings performed on element forces or displacements.

NextFEM Designer allows to handle and checks some defined quantities on nodes/elements by means of user-defined formulas.


To checks the nodes/elements the following procedure has to be done:

  • choose a quantity to check from the quantities drop-down list;
  • Choose a load case and a time/mode (or select ALL for all times/modes);
  • Import the formulas from a customized *.txt file (see chapter 4);
  • Click on the Perform checks

The results are shown on the Output window and can be exported in text format by clicking on the Export… button.

It is possible to customize the list of verifications with the notation described in the following.

Formulas can be written using the following operators/functions:

Addition: +
Multiplication: *
Division: /
Modulo: %
Exponentiation: ^
Less than: <
Less than or equal: <= or
More than: >
More than or equal: >= or
Equal: ==
Not Equal: != or
Sine: sin
Cosine: cos
Arcsine: asin
Arccosine: acos
Tangent: tan
Cotangent: cot
Arctangent: atan
Arccotangent: acot
Natural logarithm: loge
Common logarithm: log10
Logarithm: logn
Square root: sqrt

The hardcoded variables are:

  • Frame forces verifications
    • A: Area
    • Jx: Moment of Inertia around x-axis
    • Jy: Moment of Inertia around y-axis
    • Jt: Torsional Inertia
    • D: Diameter of circular cross sections
    • b: Base for any other cross sections
    • h: Height for any other cross sections
    • tw: web thickness
    • tf1: thickness of bottom flange
    • tf2: thickness of upper flange
    • t: thickness for planar sections
    • N: Axial force
    • Vy: Shear force along y direction
    • Vz: Shear force along z direction
    • Mt: Twisting moment
    • Myy: Moment around y local axis
    • Mzz: Moment around z local axis
  • Displacements
    • dx: nodal displacement in X direction
    • dy: nodal displacement in Y direction
    • dz: nodal displacement in Z direction
    • rx: nodal rotation around X axis
    • ry: nodal rotation around Y axis
    • rz: nodal rotation around Z axis