protected TriangleElement(SerializationInfo info, StreamingContext context) : base(info, context)
{
_material = (BaseMaterial)info.GetValue("_material", typeof(BaseMaterial));
_section = (Base2DSection)info.GetValue("_section", typeof(Base2DSection));
_behavior = (TriangleElementBehaviour)info.GetInt32("_behavior");
_formulation = (MembraneFormulation)info.GetInt32("_behavior");
}
internal static Matrix GetDMatrix(double e, double nu, MembraneFormulation f)
{
var d = new Matrix(3, 3);
if (f == MembraneFormulation.PlaneStress)
{
//page 23 of JAVA Thesis pdf
var cf = e / (1 - nu * nu);
d[0, 0] = d[1, 1] = 1;
d[1, 0] = d[0, 1] = nu;
d[2, 2] = (1 - nu) / 2;
d.MultiplyByConstant(cf);
}
else
{
//page 24 of JAVA Thesis pdf
var cf = e / ((1 + nu) * (1 - 2 * nu));
d[0, 0] = d[1, 1] = 1 - nu;
d[1, 0] = d[0, 1] = nu;
d[2, 2] = (1 - 2 * nu) / 2;
d.MultiplyByConstant(cf);
}
return(d);
}
/// <summary>
/// Initializes a new instance of the <see cref="CstElement"/> class.
/// </summary>
/// <param name="info">The information.</param>
/// <param name="context">The context.</param>
protected CstElement(SerializationInfo info, StreamingContext context)
: base(info, context)
{
this._thickness = info.GetDouble("_thickness");
this._poissonRatio = info.GetDouble("_poissonRatio");
this._elasticModulus = info.GetDouble("_elasticModulus");
this._formulationType = (MembraneFormulation)info.GetInt32("_formulationType");
}
/// <summary>
/// Initializes a new instance of the <see cref="DktElement"/> class.
/// </summary>
/// <param name="info">The information.</param>
/// <param name="context">The context.</param>
protected TriangleFlatShell(SerializationInfo info, StreamingContext context) : base(info, context)
{
this._thickness = info.GetDouble("_thickness");
this._poissonRatio = info.GetDouble("_poissonRatio");
this._elasticModulus = info.GetDouble("_elasticModulus");
this._addDrillingDof = info.GetBoolean("_addDrillingDof");
this._behaviour = (FlatShellBehaviour)info.GetInt32("_behaviour");
this._formulationType = (MembraneFormulation)info.GetInt32("_formulationType");
}
/// <summary>
/// Gets the stiffness matrix of DKT element.
/// </summary>
/// <param name="x">The x location of points, in local coordinates.</param>
/// <param name="y">The y location of points, in local coordinates.</param>
/// <param name="t">The thickness.</param>
/// <param name="e">The elastic modulus.</param>
/// <param name="nu">The Poisson ratio.</param>
/// <returns></returns>
internal static Matrix GetStiffnessMatrix(double[] x, double[] y, double t, double e, double nu, MembraneFormulation f)
{
double a;//area
{
var x31 = x[2] - x[0];
var x12 = x[0] - x[1];
var y31 = y[2] - y[0];
var y12 = y[0] - y[1];
a = 0.5 * Math.Abs(x31 * y12 - x12 * y31);
}
var d = GetDMatrix(e, nu, f);
var b = GetBMatrix(0, 0, x, y);//only one Gaussian point
var klocal = b.Transpose() * d * b;
klocal.MultiplyByConstant(t * a);
return(klocal);
}
