private static void TestBeam3DElasticNonlinearNewmarkDynamicAnalysisExample()
{
double youngModulus = 21000.0;
double poissonRatio = 0.3;
double nodalLoad = 20000.0;
double area = 91.04;
double inertiaY = 2843.0;
double inertiaZ = 8091.0;
double torsionalInertia = 76.57;
double effectiveAreaY = 91.04;
double effectiveAreaZ = 91.04;
double density = 7.85;
int nNodes = 3;
int nElems = 2;
int monitorNode = 3;
// Create new 3D material
var material = new ElasticMaterial3D
{
YoungModulus = youngModulus,
PoissonRatio = poissonRatio,
};
// Node creation
IList <Node> nodes = new List <Node>();
Node node1 = new Node(id: 1, x: 0.0, y: 0.0, z: 0.0);
Node node2 = new Node(id: 2, x: 300.0, y: 0.0, z: 0.0);
Node node3 = new Node(id: 3, x: 600.0, y: 0.0, z: 0.0);
nodes.Add(node1);
nodes.Add(node2);
nodes.Add(node3);
// Model creation
Model model = new Model();
// Add a single subdomain to the model
int subdomainID = 0;
model.SubdomainsDictionary.Add(subdomainID, new Subdomain(subdomainID));
// Add nodes to the nodes dictonary of the model
for (int i = 0; i < nodes.Count; ++i)
{
model.NodesDictionary.Add(i + 1, nodes[i]);
}
// Constrain bottom nodes of the model
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.TranslationX
});
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.TranslationY
});
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.TranslationZ
});
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.RotationX
});
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.RotationY
});
model.NodesDictionary[1].Constraints.Add(new Constraint {
DOF = StructuralDof.RotationZ
});
// Generate elements of the structure
int iNode = 1;
for (int iElem = 0; iElem < nElems; iElem++)
{
// element nodes
IList <Node> elementNodes = new List <Node>();
elementNodes.Add(model.NodesDictionary[iNode]);
elementNodes.Add(model.NodesDictionary[iNode + 1]);
// Create new Beam3D section and element
var beamSection = new BeamSection3D(area, inertiaY, inertiaZ, torsionalInertia, effectiveAreaY, effectiveAreaZ);
var beam = new Beam3DCorotationalQuaternion(elementNodes, material, density, beamSection);
// Create elements
var element = new Element()
{
ID = iElem + 1,
ElementType = beam
};
// Add nodes to the created element
element.AddNode(model.NodesDictionary[iNode]);
element.AddNode(model.NodesDictionary[iNode + 1]);
var a = beam.StiffnessMatrix(element);
var b = beam.MassMatrix(element);
// Add beam element to the element and subdomains dictionary of the model
model.ElementsDictionary.Add(element.ID, element);
model.SubdomainsDictionary[subdomainID].Elements.Add(element);
iNode++;
}
// Add nodal load values at the top nodes of the model
model.Loads.Add(new Load()
{
Amount = nodalLoad, Node = model.NodesDictionary[monitorNode], DOF = StructuralDof.TranslationY
});
// Solver
var solverBuilder = new SkylineSolver.Builder();
ISolver solver = solverBuilder.BuildSolver(model);
// Problem type
var provider = new ProblemStructural(model, solver);
// Analyzers
int increments = 10;
var childAnalyzerBuilder = new LoadControlAnalyzer.Builder(model, solver, provider, increments);
childAnalyzerBuilder.MaxIterationsPerIncrement = 120;
childAnalyzerBuilder.NumIterationsForMatrixRebuild = 500;
//childAnalyzerBuilder.SubdomainUpdaters = new[] { new NonLinearSubdomainUpdater(model.SubdomainsDictionary[subdomainID]) }; // This is the default
LoadControlAnalyzer childAnalyzer = childAnalyzerBuilder.Build();
var parentAnalyzerBuilder = new NewmarkDynamicAnalyzer.Builder(model, solver, provider, childAnalyzer, 0.28, 3.36);
parentAnalyzerBuilder.SetNewmarkParametersForConstantAcceleration(); // Not necessary. This is the default
NewmarkDynamicAnalyzer parentAnalyzer = parentAnalyzerBuilder.Build();
parentAnalyzer.Initialize();
parentAnalyzer.Solve();
Assert.Equal(148.936792350562, solver.LinearSystems[subdomainID].Solution[7], 12);
}
