/// <inheritdoc/>
public ElementPermuteHelper.ElementLocalDof[] GetDofOrder(Element targetElement)
{
var buf = new ElementPermuteHelper.ElementLocalDof[]
{
new ElementPermuteHelper.ElementLocalDof(0, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Ry),
};
return(buf);
}
/// <inheritdoc />
public override Matrix GetGlobalStifnessMatrix()
{
//step 1 : get points in local system
//step 2 : get local stiffness matrix
//step 3 : expand local stiffness matrix
//step 4 : get global stiffness matrix
//step 1
var ls = GetLocalPoints();
var xs = new double[] { ls[0].X, ls[1].X, ls[2].X };
var ys = new double[] { ls[0].Y, ls[1].Y, ls[2].Y };
//step 2
var kl = DktElement.GetStiffnessMatrix(xs, ys, this._thickness, this.ElasticModulus, this.PoissonRatio);
//step 3
var currentOrder = new ElementPermuteHelper.ElementLocalDof[]
{
new ElementPermuteHelper.ElementLocalDof(0, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Ry),
};
var kle = ElementPermuteHelper.FullyExpand(kl, currentOrder, 3);
var lambda = GetTransformationMatrix();
var t = lambda.Transpose().RepeatDiagonally(6); // eq. 5-16 page 78 (87 of file)
//step 4 : get global stiffness matrix
var buf = t.Transpose() * kle * t; //eq. 5-15 p77
return(buf);
}
public Matrix GetLocalPlateBendingStiffnessMatrix()
{
//dkt
//step 1 : get points in local system
//step 2 : get local stiffness matrix
//step 3 : expand local stiffness matrix
//step 4 : get global stiffness matrix
//step 1
var ls = GetLocalPoints();
var xs = new double[] { ls[0].X, ls[1].X, ls[2].X };
var ys = new double[] { ls[0].Y, ls[1].Y, ls[2].Y };
//step 2
var kl = DktElement.GetStiffnessMatrix(xs, ys, this._thickness, this.ElasticModulus, this.PoissonRatio);
//step 3
var currentOrder = new ElementPermuteHelper.ElementLocalDof[]
{
new ElementPermuteHelper.ElementLocalDof(0, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(0, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(1, DoF.Ry),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Dz),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Rx),
new ElementPermuteHelper.ElementLocalDof(2, DoF.Ry),
};
var kle = ElementPermuteHelper.FullyExpand(kl, currentOrder, 3);
return(kle);
}
