[StructuralMechanicsApp] Adding Total Lagrangian 2 noded truss elements (2D and 3D)

applications/StructuralMechanicsApplication/custom_elements/truss_elements/linear_truss_element.cpp

@@ -711,6 +711,11 @@ void LinearTrussElement<TDimension, TNNodes>::CalculateOnIntegrationPoints(
         SystemSizeBoundedArrayType B;
         const double area = GetProperties()[CROSS_AREA];
 
+        double pre_stress = 0.0;
+        if (GetProperties().Has(TRUSS_PRESTRESS_PK2)) {
+            pre_stress = GetProperties()[TRUSS_PRESTRESS_PK2];
+        }
+
         // Loop over the integration points
         for (SizeType IP = 0; IP < integration_points.size(); ++IP) {
             const double xi = integration_points[IP].X();
@@ -720,11 +725,6 @@ void LinearTrussElement<TDimension, TNNodes>::CalculateOnIntegrationPoints(
 
             mConstitutiveLawVector[IP]->CalculateMaterialResponsePK2(cl_values);
 
-            double pre_stress = 0.0;
-            if (GetProperties().Has(TRUSS_PRESTRESS_PK2)) {
-                pre_stress = GetProperties()[TRUSS_PRESTRESS_PK2];
-            }
-
             rOutput[IP] = (cl_values.GetStressVector()[0] + pre_stress) * area;
         }
     } else if (rVariable == AXIAL_STRAIN) {