diff --git a/StructureHelper.csproj b/StructureHelper.csproj
index 80a9cca..14efb18 100644
--- a/StructureHelper.csproj
+++ b/StructureHelper.csproj
@@ -264,7 +264,8 @@
     <Compile Include="Windows\ViewModels\Materials\PartialFactorsViewModel.cs" />
     <Compile Include="Windows\ViewModels\Materials\SafetyFactorsViewModel.cs" />
     <Compile Include="Windows\ViewModels\Forces\ActionsViewModel.cs" />
-    <Compile Include="Windows\ViewModels\NdmCrossSections\AnalysisVewModel.cs" />
+    <Compile Include="Windows\ViewModels\NdmCrossSections\AnalysisVewModelLogic.cs" />
+    <Compile Include="Windows\ViewModels\NdmCrossSections\SecondOrderViewModel.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\IPrimitiveViewModelLogic.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\PrimitiveViewModelLogic.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\CrossSectionViewVisualProperty.cs" />
@@ -278,7 +279,6 @@
     <Compile Include="Windows\ViewModels\ICRUDViewModel.cs" />
     <Compile Include="Windows\ViewModels\ISourceToTargetViewModel.cs" />
     <Compile Include="Windows\ViewModels\Materials\HeadMaterialsViewModel.cs" />
-    <Compile Include="Windows\ViewModels\NdmCrossSections\CalculatorsViewModelLogic.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\ForceCombinationViewModelLogic.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\ICalculatorsViewModelLogic.cs" />
     <Compile Include="Windows\ViewModels\NdmCrossSections\IForceCombinationViewModelLogic.cs" />
diff --git a/StructureHelperCommon/Models/Calculators/Accuracy.cs b/StructureHelperCommon/Models/Calculators/Accuracy.cs
new file mode 100644
index 0000000..67ca68e
--- /dev/null
+++ b/StructureHelperCommon/Models/Calculators/Accuracy.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Calculators
+{
+    public class Accuracy : IAccuracy
+    {
+        public double IterationAccuracy { get; set; }
+        public int MaxIterationCount { get; set; }
+    }
+}
diff --git a/StructureHelperCommon/Models/Calculators/IAccuracy.cs b/StructureHelperCommon/Models/Calculators/IAccuracy.cs
new file mode 100644
index 0000000..4ca1bd4
--- /dev/null
+++ b/StructureHelperCommon/Models/Calculators/IAccuracy.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Calculators
+{
+    public interface IAccuracy
+    {
+        double IterationAccuracy { get; set; }
+        int MaxIterationCount { get; set; }
+    }
+}
diff --git a/StructureHelperCommon/Models/Sections/CompressedMember.cs b/StructureHelperCommon/Models/Sections/CompressedMember.cs
new file mode 100644
index 0000000..7c2722f
--- /dev/null
+++ b/StructureHelperCommon/Models/Sections/CompressedMember.cs
@@ -0,0 +1,37 @@
+using StructureHelperCommon.Services.Sections;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Sections
+{
+    public class CompressedMember : ICompressedMember
+    {
+        public bool Buckling { get; set; }
+        public double GeometryLength { get; set; }
+        public double LengthFactorX { get; set; }
+        public double DiagramFactorX { get; set; }
+        public double LengthFactorY { get; set; }
+        public double DiagramFactorY { get; set; }
+        
+
+        public CompressedMember()
+        {
+            Buckling = true;
+            GeometryLength = 3d;
+            LengthFactorX = 1d;
+            DiagramFactorX = 1d;
+            LengthFactorY = 1d;
+            DiagramFactorY = 1d;
+        }
+
+        public object Clone()
+        {
+            var target = new CompressedMember();
+            CompressedMemberServices.CopyProperties(this, target);
+            return target;
+        }
+    }
+}
diff --git a/StructureHelperCommon/Models/Sections/ICompressedMember.cs b/StructureHelperCommon/Models/Sections/ICompressedMember.cs
new file mode 100644
index 0000000..e3b3cb1
--- /dev/null
+++ b/StructureHelperCommon/Models/Sections/ICompressedMember.cs
@@ -0,0 +1,18 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Models.Sections
+{
+    public interface ICompressedMember : ICloneable
+    {
+        bool Buckling { get; set; }
+        double GeometryLength { get; set; }
+        double LengthFactorX { get; set; }
+        double DiagramFactorX { get; set; }
+        double LengthFactorY { get; set; }
+        double DiagramFactorY { get; set; }
+    }
+}
diff --git a/StructureHelperCommon/Services/Calculations/AccuracyService.cs b/StructureHelperCommon/Services/Calculations/AccuracyService.cs
new file mode 100644
index 0000000..c56bd0c
--- /dev/null
+++ b/StructureHelperCommon/Services/Calculations/AccuracyService.cs
@@ -0,0 +1,19 @@
+using LoaderCalculator;
+using StructureHelperCommon.Models.Calculators;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Services.Calculations
+{
+    public static class AccuracyService
+    {
+        public static void CopyProperties(IAccuracy source, IAccuracy target)
+        {
+            target.IterationAccuracy = source.IterationAccuracy;
+            target.MaxIterationCount = source.MaxIterationCount;
+        }
+    }
+}
diff --git a/StructureHelperCommon/Services/Sections/CompressedMemberServices.cs b/StructureHelperCommon/Services/Sections/CompressedMemberServices.cs
new file mode 100644
index 0000000..e38a53e
--- /dev/null
+++ b/StructureHelperCommon/Services/Sections/CompressedMemberServices.cs
@@ -0,0 +1,22 @@
+using StructureHelperCommon.Models.Sections;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelperCommon.Services.Sections
+{
+    public static class CompressedMemberServices
+    {
+        public static void CopyProperties(ICompressedMember source, ICompressedMember target)
+        {
+            target.Buckling = source.Buckling;
+            target.GeometryLength = source.GeometryLength;
+            target.LengthFactorX = source.LengthFactorX;
+            target.DiagramFactorX = source.DiagramFactorX;
+            target.LengthFactorY = source.LengthFactorY;
+            target.DiagramFactorY = source.DiagramFactorY;
+        }
+    }
+}
diff --git a/StructureHelperCommon/StructureHelperCommon.csproj b/StructureHelperCommon/StructureHelperCommon.csproj
index 6874bd7..5faf8c6 100644
--- a/StructureHelperCommon/StructureHelperCommon.csproj
+++ b/StructureHelperCommon/StructureHelperCommon.csproj
@@ -61,6 +61,8 @@
     <Compile Include="Infrastructures\Settings\ProgramSetting.cs" />
     <Compile Include="Infrastructures\Strings\ErrorString.cs" />
     <Compile Include="Infrastructures\Enums\MaterialTypes.cs" />
+    <Compile Include="Models\Calculators\Accuracy.cs" />
+    <Compile Include="Models\Calculators\IAccuracy.cs" />
     <Compile Include="Models\Calculators\IHelperCalculator.cs" />
     <Compile Include="Models\Forces\DesignForceTuple.cs" />
     <Compile Include="Models\Forces\Factories\DesignForceFactory.cs" />
@@ -86,6 +88,8 @@
     <Compile Include="Models\Materials\Libraries\MaterialPartialFactor.cs" />
     <Compile Include="Models\Materials\Libraries\MaterialSafetyFactor.cs" />
     <Compile Include="Models\Materials\Libraries\ReinforcementMaterialEntity.cs" />
+    <Compile Include="Models\Sections\CompressedMember.cs" />
+    <Compile Include="Models\Sections\ICompressedMember.cs" />
     <Compile Include="Models\Shapes\Point2D.cs" />
     <Compile Include="Models\Shapes\IPoint2D.cs" />
     <Compile Include="Models\Shapes\ICenterShape.cs" />
@@ -98,9 +102,11 @@
     <Compile Include="Models\Shapes\PointShape.cs" />
     <Compile Include="Models\Shapes\RectangleShape.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
+    <Compile Include="Services\Calculations\AccuracyService.cs" />
     <Compile Include="Services\ColorServices\ColorProcessor.cs" />
     <Compile Include="Services\Forces\ForceTupleService.cs" />
     <Compile Include="Services\Forces\StrainTupleService.cs" />
+    <Compile Include="Services\Sections\CompressedMemberServices.cs" />
     <Compile Include="Services\ShapeServices\ShapeService.cs" />
     <Compile Include="Services\Units\IUnit.cs" />
     <Compile Include="Services\Units\Unit.cs" />
diff --git a/StructureHelperLogics/NdmCalculations/Analyses/ByForces/ForceCalculator.cs b/StructureHelperLogics/NdmCalculations/Analyses/ByForces/ForceCalculator.cs
index 9063e50..6a47239 100644
--- a/StructureHelperLogics/NdmCalculations/Analyses/ByForces/ForceCalculator.cs
+++ b/StructureHelperLogics/NdmCalculations/Analyses/ByForces/ForceCalculator.cs
@@ -3,9 +3,13 @@ using LoaderCalculator.Data.Matrix;
 using LoaderCalculator.Data.Ndms;
 using LoaderCalculator.Data.SourceData;
 using StructureHelperCommon.Infrastructures.Enums;
+using StructureHelperCommon.Models.Calculators;
 using StructureHelperCommon.Models.Forces;
+using StructureHelperCommon.Models.Sections;
 using StructureHelperCommon.Models.Shapes;
+using StructureHelperCommon.Services.Calculations;
 using StructureHelperCommon.Services.Forces;
+using StructureHelperCommon.Services.Sections;
 using StructureHelperLogics.NdmCalculations.Primitives;
 using StructureHelperLogics.Services.NdmPrimitives;
 using System;
@@ -17,14 +21,13 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
     public class ForceCalculator : IForceCalculator
     {
         public string Name { get; set; }
-        public double IterationAccuracy { get; set; }
-        public int MaxIterationCount { get; set; }
         public List<LimitStates> LimitStatesList { get; }
         public List<CalcTerms> CalcTermsList { get; }
         public List<IForceCombinationList> ForceCombinationLists { get; }
         public List<INdmPrimitive> Primitives { get; }
         public INdmResult Result { get; private set; }
-
+        public ICompressedMember CompressedMember { get; }
+        public IAccuracy Accuracy { get; }
 
         public void Run()
         {
@@ -82,8 +85,8 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
         {
             ForceCombinationLists = new List<IForceCombinationList>();
             Primitives = new List<INdmPrimitive>();
-            IterationAccuracy = 0.001d;
-            MaxIterationCount = 1000;
+            CompressedMember = new CompressedMember();
+            Accuracy = new Accuracy() { IterationAccuracy = 0.001d, MaxIterationCount = 1000 };
             LimitStatesList = new List<LimitStates>() { LimitStates.ULS, LimitStates.SLS };
             CalcTermsList = new List<CalcTerms>() { CalcTerms.ShortTerm, CalcTerms.LongTerm };
         }
@@ -100,8 +103,8 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
                 {
                     Preconditions = new Preconditions
                     {
-                        ConditionRate = IterationAccuracy,
-                        MaxIterationCount = MaxIterationCount,
+                        ConditionRate = Accuracy.IterationAccuracy,
+                        MaxIterationCount = Accuracy.MaxIterationCount,
                         StartForceMatrix = new ForceMatrix { Mx = mx, My = my, Nz = nz }
                     },
                     NdmCollection = ndmCollection
@@ -109,7 +112,7 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
                 var calculator = new Calculator();
                 calculator.Run(loaderData, new CancellationToken());
                 var calcResult = calculator.Result;
-                if (calcResult.AccuracyRate <= IterationAccuracy)
+                if (calcResult.AccuracyRate <= Accuracy.IterationAccuracy)
                 {
                     return new ForcesResult() { IsValid = true, Desctription = "Analysis is done succsefully", LoaderResults = calcResult };
                 }
@@ -131,17 +134,16 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
 
         public object Clone()
         {
-            IForceCalculator calculator = new ForceCalculator();
-            calculator.Name = Name + " copy";
-            calculator.LimitStatesList.Clear();
-            calculator.LimitStatesList.AddRange(LimitStatesList);
-            calculator.CalcTermsList.Clear();
-            calculator.CalcTermsList.AddRange(CalcTermsList);
-            calculator.IterationAccuracy = IterationAccuracy;
-            calculator.MaxIterationCount = MaxIterationCount;
-            calculator.Primitives.AddRange(Primitives);
-            calculator.ForceCombinationLists.AddRange(ForceCombinationLists);
-            return calculator;
+            IForceCalculator target = new ForceCalculator { Name = Name + " copy"};
+            target.LimitStatesList.Clear();
+            target.LimitStatesList.AddRange(LimitStatesList);
+            target.CalcTermsList.Clear();
+            target.CalcTermsList.AddRange(CalcTermsList);
+            AccuracyService.CopyProperties(Accuracy, target.Accuracy);
+            CompressedMemberServices.CopyProperties(CompressedMember, target.CompressedMember);
+            target.Primitives.AddRange(Primitives);
+            target.ForceCombinationLists.AddRange(ForceCombinationLists);
+            return target;
         }
     }
 }
diff --git a/StructureHelperLogics/NdmCalculations/Analyses/ByForces/IForceCalculator.cs b/StructureHelperLogics/NdmCalculations/Analyses/ByForces/IForceCalculator.cs
index a7555f3..ebf5d12 100644
--- a/StructureHelperLogics/NdmCalculations/Analyses/ByForces/IForceCalculator.cs
+++ b/StructureHelperLogics/NdmCalculations/Analyses/ByForces/IForceCalculator.cs
@@ -1,6 +1,8 @@
 using StructureHelperCommon.Infrastructures.Enums;
 using StructureHelperCommon.Infrastructures.Interfaces;
+using StructureHelperCommon.Models.Calculators;
 using StructureHelperCommon.Models.Forces;
+using StructureHelperCommon.Models.Sections;
 using StructureHelperLogics.NdmCalculations.Primitives;
 using System;
 using System.Collections.Generic;
@@ -10,8 +12,8 @@ namespace StructureHelperLogics.NdmCalculations.Analyses.ByForces
     public interface IForceCalculator : INdmCalculator, IHasPrimitives, IHasForceCombinations
     {
         List<CalcTerms> CalcTermsList { get; }
-        double IterationAccuracy { get; set; }
         List<LimitStates> LimitStatesList { get; }
-        int MaxIterationCount { get; set; }
+        ICompressedMember CompressedMember { get; }
+        IAccuracy Accuracy { get; }
     }
 }
\ No newline at end of file
diff --git a/StructureHelperLogics/Services/NdmCalculations/InterpolateService.cs b/StructureHelperLogics/Services/NdmCalculations/InterpolateService.cs
index ee11f7d..11ced04 100644
--- a/StructureHelperLogics/Services/NdmCalculations/InterpolateService.cs
+++ b/StructureHelperLogics/Services/NdmCalculations/InterpolateService.cs
@@ -19,8 +19,8 @@ namespace StructureHelperLogics.Services.NdmCalculations
             calculator.LimitStatesList.Add(finishDesignForce.LimitState);
             calculator.CalcTermsList.Clear();
             calculator.CalcTermsList.Add(finishDesignForce.CalcTerm);
-            calculator.IterationAccuracy = source.IterationAccuracy;
-            calculator.MaxIterationCount = source.MaxIterationCount;
+            calculator.Accuracy.IterationAccuracy = source.Accuracy.IterationAccuracy;
+            calculator.Accuracy.MaxIterationCount = source.Accuracy.MaxIterationCount;
             calculator.Primitives.AddRange(source.Primitives);
             calculator.ForceCombinationLists.Clear();
             var combination = new ForceCombinationList()
diff --git a/Windows/CalculationWindows/CalculatorsViews/ForceCalculatorViews/ForceCalculatorView.xaml b/Windows/CalculationWindows/CalculatorsViews/ForceCalculatorViews/ForceCalculatorView.xaml
index df2b42e..2363cdf 100644
--- a/Windows/CalculationWindows/CalculatorsViews/ForceCalculatorViews/ForceCalculatorView.xaml
+++ b/Windows/CalculationWindows/CalculatorsViews/ForceCalculatorViews/ForceCalculatorView.xaml
@@ -49,6 +49,31 @@
             <TabItem Header="Primitives">
                 <ContentControl ContentTemplate="{StaticResource SourceToTarget}" Content="{Binding PrimitivesViewModel}"/>
             </TabItem>
+            <TabItem Header="SOrder" Visibility="Hidden">
+                <Grid DataContext="{Binding SecondOrder}">
+                    <Grid.ColumnDefinitions>
+                        <ColumnDefinition/>
+                        <ColumnDefinition/>
+                    </Grid.ColumnDefinitions>
+                    <Grid.RowDefinitions>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition Height="22"/>
+                        <RowDefinition/>
+                    </Grid.RowDefinitions>
+                    <TextBlock Text="Consider second order effects"/>
+                    <TextBlock Grid.Row="1" Text="Geometry length"/>
+                    <TextBlock Grid.Row="2" Text="Buckling factor x-axis"/>
+                    <TextBlock Grid.Row="3" Text="Buckling factor y-axis"/>
+                    <CheckBox Grid.Column="1" IsChecked="{Binding Buckling}"/>
+                    <TextBox Grid.Row="1" Grid.Column="1" Text="{Binding GeometryLength, Converter={StaticResource LengthConverter}, ValidatesOnExceptions=True}"/>
+                    <TextBox Grid.Row="2" Grid.Column="1" Text="{Binding LengthFactorX, Converter={StaticResource PlainDouble}, ValidatesOnExceptions=True}"/>
+                    <TextBox Grid.Row="3" Grid.Column="1" Text="{Binding LengthFactorY, Converter={StaticResource PlainDouble}, ValidatesOnExceptions=True}"/>
+                </Grid>
+            </TabItem>
             <TabItem Header="Iterations">
                 <Grid>
                     <Grid.RowDefinitions>
diff --git a/Windows/MainWindow/MainViewModel.cs b/Windows/MainWindow/MainViewModel.cs
index 047ad93..7feb8af 100644
--- a/Windows/MainWindow/MainViewModel.cs
+++ b/Windows/MainWindow/MainViewModel.cs
@@ -43,8 +43,8 @@ namespace StructureHelper.Windows.MainWindow
         public PrimitiveBase SelectedPrimitive { get; set; }
         public IForceCombinationList SelectedForceCombinationList { get; set; }
 
-        private readonly AnalysisVewModel calculatorsLogic;
-        public AnalysisVewModel CalculatorsLogic { get => calculatorsLogic;}
+        private readonly AnalysisVewModelLogic calculatorsLogic;
+        public AnalysisVewModelLogic CalculatorsLogic { get => calculatorsLogic;}
         public ActionsViewModel CombinationsLogic { get => combinationsLogic; }
         public IPrimitiveViewModelLogic PrimitiveLogic => primitiveLogic;
 
@@ -202,7 +202,7 @@ namespace StructureHelper.Windows.MainWindow
             Model = model;
             section = model.Section;
             combinationsLogic = new ActionsViewModel(repository);
-            calculatorsLogic = new AnalysisVewModel(repository);
+            calculatorsLogic = new AnalysisVewModelLogic(repository);
             primitiveLogic = new PrimitiveViewModelLogic(repository) { CanvasWidth = CanvasWidth, CanvasHeight = CanvasHeight };
             XX2 = CanvasWidth;
             XY1 = CanvasHeight / 2d;
diff --git a/Windows/PrimitivePropertiesWindow/PrimitivePropertiesView.xaml b/Windows/PrimitivePropertiesWindow/PrimitivePropertiesView.xaml
index 6c08e23..b59edfe 100644
--- a/Windows/PrimitivePropertiesWindow/PrimitivePropertiesView.xaml
+++ b/Windows/PrimitivePropertiesWindow/PrimitivePropertiesView.xaml
@@ -83,28 +83,24 @@
                             <TextBlock Grid.Row="2" Text="Center X"/>
                             <TextBlock Grid.Row="3" Text="Center Y"/>
                             <TextBox Grid.Row="0" Grid.Column="1" Margin="1" Text="{Binding Name}"/>
-                            <StackPanel Grid.Row="1" Grid.Column="1" Orientation="Horizontal" HorizontalAlignment="Left">
-                                <ComboBox Width="100" ItemsSource="{Binding HeadMaterials}" SelectedItem="{Binding PrimitiveMaterial}">
-                                    <ComboBox.ItemTemplate>
-                                        <DataTemplate>
-                                            <Grid>
-                                                <Grid.ColumnDefinitions>
-                                                    <ColumnDefinition Width="20"/>
-                                                    <ColumnDefinition/>
-                                                </Grid.ColumnDefinitions>
-                                                <Rectangle Grid.Column="0" Margin="3">
-                                                    <Rectangle.Fill>
-                                                        <SolidColorBrush Color="{Binding Color}"/>
-                                                    </Rectangle.Fill>
-                                                </Rectangle>
-                                                <TextBlock Grid.Column="1" Text="{Binding Name}"/>
-                                            </Grid>
-                                        </DataTemplate>
-                                    </ComboBox.ItemTemplate>
-                                </ComboBox>
-                                <Button Width="50" Content="..." Command="{Binding EditMaterialCommand}">
-                                </Button>
-                            </StackPanel>
+                            <ComboBox Grid.Row="1" Grid.Column="1" ItemsSource="{Binding HeadMaterials}" SelectedItem="{Binding PrimitiveMaterial}">
+                                <ComboBox.ItemTemplate>
+                                    <DataTemplate>
+                                        <Grid>
+                                            <Grid.ColumnDefinitions>
+                                                <ColumnDefinition Width="20"/>
+                                                <ColumnDefinition/>
+                                            </Grid.ColumnDefinitions>
+                                            <Rectangle Grid.Column="0" Margin="3">
+                                                <Rectangle.Fill>
+                                                    <SolidColorBrush Color="{Binding Color}"/>
+                                                </Rectangle.Fill>
+                                            </Rectangle>
+                                            <TextBlock Grid.Column="1" Text="{Binding Name}"/>
+                                        </Grid>
+                                    </DataTemplate>
+                                </ComboBox.ItemTemplate>
+                            </ComboBox>
                             <TextBox Grid.Row="2" Grid.Column="1" Margin="1" Text="{Binding CenterX, Converter={StaticResource LengthConverter}, ValidatesOnExceptions=True}"/>
                             <TextBox Grid.Row="3" Grid.Column="1" Margin="1" Text="{Binding CenterY, Converter={StaticResource LengthConverter}, ValidatesOnExceptions=True}"/>
                         </Grid>
diff --git a/Windows/ViewModels/Calculations/Calculators/ForceCalculatorViewModel.cs b/Windows/ViewModels/Calculations/Calculators/ForceCalculatorViewModel.cs
index b0c19ef..6551470 100644
--- a/Windows/ViewModels/Calculations/Calculators/ForceCalculatorViewModel.cs
+++ b/Windows/ViewModels/Calculations/Calculators/ForceCalculatorViewModel.cs
@@ -1,6 +1,7 @@
 using StructureHelper.Infrastructure;
 using StructureHelper.Infrastructure.UI.DataContexts;
 using StructureHelper.Services.Primitives;
+using StructureHelper.Windows.ViewModels.NdmCrossSections;
 using StructureHelperCommon.Infrastructures.Enums;
 using StructureHelperCommon.Infrastructures.Exceptions;
 using StructureHelperCommon.Infrastructures.Strings;
@@ -25,6 +26,7 @@ namespace StructureHelper.Windows.ViewModels.Calculations.Calculators
         IEnumerable<INdmPrimitive> allowedPrimitives;
         IEnumerable<IForceCombinationList> allowedForceCombinations;
         ForceCalculator forcesCalculator;
+        SecondOrderViewModel secondOrderViewModel;
 
         public string Name
         {
@@ -34,16 +36,18 @@ namespace StructureHelper.Windows.ViewModels.Calculations.Calculators
 
         public double IterationAccuracy
         {
-            get { return forcesCalculator.IterationAccuracy; }
-            set { forcesCalculator.IterationAccuracy = value;}
+            get { return forcesCalculator.Accuracy.IterationAccuracy; }
+            set { forcesCalculator.Accuracy.IterationAccuracy = value;}
         }
 
         public int MaxIterationCount
         {
-            get { return forcesCalculator.MaxIterationCount; }
-            set { forcesCalculator.MaxIterationCount = value; }
+            get { return forcesCalculator.Accuracy.MaxIterationCount; }
+            set { forcesCalculator.Accuracy.MaxIterationCount = value; }
         }
 
+        public SecondOrderViewModel SecondOrder => secondOrderViewModel;
+
         public bool ULS { get; set; }
         public bool SLS { get; set; }
         public bool ShortTerm { get; set; }
@@ -147,6 +151,7 @@ namespace StructureHelper.Windows.ViewModels.Calculations.Calculators
             allowedPrimitives = _allowedPrimitives;
             allowedForceCombinations = _allowedForceCombinations;
             forcesCalculator = _forcesCalculator;
+            secondOrderViewModel = new SecondOrderViewModel(forcesCalculator.CompressedMember);
 
             CombinationViewModel = new SourceToTargetViewModel<IForceCombinationList>();
             CombinationViewModel.SetTargetItems(forcesCalculator.ForceCombinationLists);
diff --git a/Windows/ViewModels/NdmCrossSections/AnalysisVewModel.cs b/Windows/ViewModels/NdmCrossSections/AnalysisVewModelLogic.cs
similarity index 93%
rename from Windows/ViewModels/NdmCrossSections/AnalysisVewModel.cs
rename to Windows/ViewModels/NdmCrossSections/AnalysisVewModelLogic.cs
index ba1c6f7..2fdb818 100644
--- a/Windows/ViewModels/NdmCrossSections/AnalysisVewModel.cs
+++ b/Windows/ViewModels/NdmCrossSections/AnalysisVewModelLogic.cs
@@ -15,7 +15,7 @@ using System.Windows.Forms;
 
 namespace StructureHelper.Windows.ViewModels.NdmCrossSections
 {
-    public class AnalysisVewModel : CRUDViewModelBase<INdmCalculator>
+    public class AnalysisVewModelLogic : CRUDViewModelBase<INdmCalculator>
     {
         private ICrossSectionRepository repository;
         private RelayCommand runCommand;
@@ -69,7 +69,7 @@ namespace StructureHelper.Windows.ViewModels.NdmCrossSections
                 }, o => SelectedItem != null));
             }
         }
-        public AnalysisVewModel(ICrossSectionRepository sectionRepository) : base(sectionRepository.CalculatorsList)
+        public AnalysisVewModelLogic(ICrossSectionRepository sectionRepository) : base(sectionRepository.CalculatorsList)
         {
             repository = sectionRepository;
         }
diff --git a/Windows/ViewModels/NdmCrossSections/CalculatorsViewModelLogic.cs b/Windows/ViewModels/NdmCrossSections/CalculatorsViewModelLogic.cs
deleted file mode 100644
index d6f2019..0000000
--- a/Windows/ViewModels/NdmCrossSections/CalculatorsViewModelLogic.cs
+++ /dev/null
@@ -1,153 +0,0 @@
-using StructureHelper.Infrastructure;
-using StructureHelper.Windows.CalculationWindows.CalculatorsViews.ForceCalculatorViews;
-using StructureHelper.Windows.ViewModels.Calculations.Calculators;
-using StructureHelperCommon.Models.Forces;
-using StructureHelperLogics.Models.CrossSections;
-using StructureHelperLogics.NdmCalculations.Analyses;
-using StructureHelperLogics.NdmCalculations.Analyses.ByForces;
-using System;
-using System.Collections.Generic;
-using System.Collections.ObjectModel;
-using System.Linq;
-using System.Windows.Forms;
-using System.Windows.Input;
-
-namespace StructureHelper.Windows.ViewModels.NdmCrossSections
-{
-    public class CalculatorsViewModelLogic : ViewModelBase, ICalculatorsViewModelLogic
-    {
-        private readonly ICrossSectionRepository repository;
-
-        public INdmCalculator SelectedItem { get; set; }
-        public ObservableCollection<INdmCalculator> Items { get; private set; }
-
-        private RelayCommand addCommand;
-        public RelayCommand Add
-        {
-            get
-            {
-                return addCommand ??
-                    (
-                    addCommand = new RelayCommand(o =>
-                    {
-                        AddCalculator();
-                        OnPropertyChanged(nameof(Items));
-                    }));
-            }
-        }
-        private void AddCalculator()
-        {
-            var item = new ForceCalculator() { Name = "New force calculator" };
-            Items.Add(item);
-            repository.CalculatorsList.Add(item);
-        }
-        private RelayCommand editCommand;
-        public RelayCommand Edit
-        {
-            get
-            {
-                return editCommand ??
-                    (
-                    editCommand = new RelayCommand(o =>
-                    {
-                        var tmpSelected = SelectedItem;
-                        EditCalculator();
-                        Items.Clear();
-                        AddItems(repository.CalculatorsList);
-                        OnPropertyChanged(nameof(Items));
-                        SelectedItem = tmpSelected;
-                    }, o => SelectedItem != null));
-            }
-        }
-        private void EditCalculator()
-        {
-            if (SelectedItem is ForceCalculator)
-            {
-                var calculator = SelectedItem as ForceCalculator;
-                var vm = new ForceCalculatorViewModel(repository.Primitives, repository.ForceCombinationLists, calculator);
-
-                var wnd = new ForceCalculatorView(vm);
-                wnd.ShowDialog();
-            }
-        }
-        private RelayCommand deleteCommand;
-        private RelayCommand runCommand;
-        private RelayCommand copyCommand;
-
-        public RelayCommand Delete
-        {
-            get
-            {
-                return deleteCommand ??
-                    (
-                    deleteCommand = new RelayCommand(o =>
-                    {
-                        DeleteCalculator();
-                    }, o => SelectedItem != null));
-            }
-        }
-        public RelayCommand Run
-        {
-            get
-            {
-                return runCommand ??
-                (
-                runCommand = new RelayCommand(o =>
-                {
-                    SelectedItem.Run();
-                    var result = SelectedItem.Result;
-                    if (result.IsValid == false)
-                    {
-                        MessageBox.Show(result.Desctription, "Check data for analisys", MessageBoxButtons.OK, MessageBoxIcon.Warning);
-                    }
-                    else
-                    {
-                        var calculator = SelectedItem as IForceCalculator;
-                        var vm = new ForcesResultsViewModel(calculator);
-                        var wnd = new ForceResultsView(vm);
-                        wnd.ShowDialog();
-                    }
-                }, o => SelectedItem != null));
-            }
-        }
-        public RelayCommand Copy
-        {
-            get
-            {
-                return copyCommand ??
-                (
-                copyCommand = new RelayCommand(o =>
-                {
-                    var item = SelectedItem.Clone() as INdmCalculator;
-                    repository.CalculatorsList.Add(item);
-                    Items.Add(item);
-                    OnPropertyChanged(nameof(Items));
-                }, o => SelectedItem != null));
-            }
-        }
-        private void DeleteCalculator()
-        {
-            var dialogResult = MessageBox.Show("Delete calculator?", "Please, confirm deleting", MessageBoxButtons.YesNo, MessageBoxIcon.Warning);
-            if (dialogResult == DialogResult.Yes)
-            {
-                repository.CalculatorsList.Remove(SelectedItem as INdmCalculator);
-                OnPropertyChanged(nameof(Items));
-            }
-        }
-
-        public void AddItems(IEnumerable<INdmCalculator> items)
-        {
-            foreach (var item in items)
-            {
-                Items.Add(item);
-            }
-        }
-
-        public CalculatorsViewModelLogic(ICrossSectionRepository repository)
-        {
-            this.repository = repository;
-            Items = new ObservableCollection<INdmCalculator>();
-            AddItems(this.repository.CalculatorsList);
-        }
-    }
-}
diff --git a/Windows/ViewModels/NdmCrossSections/SecondOrderViewModel.cs b/Windows/ViewModels/NdmCrossSections/SecondOrderViewModel.cs
new file mode 100644
index 0000000..fe267b0
--- /dev/null
+++ b/Windows/ViewModels/NdmCrossSections/SecondOrderViewModel.cs
@@ -0,0 +1,60 @@
+using FieldVisualizer.ViewModels;
+using StructureHelperCommon.Models.Sections;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace StructureHelper.Windows.ViewModels.NdmCrossSections
+{
+    public class SecondOrderViewModel : ViewModelBase
+    {
+        ICompressedMember member;
+
+        public bool Buckling
+        {
+            get => member.Buckling;
+            set
+            {
+                member.Buckling = value;
+                OnPropertyChanged(nameof(Buckling));
+            }
+        }
+
+        public double GeometryLength
+        {
+            get => member.GeometryLength;
+            set
+            {
+                member.GeometryLength = value;
+                OnPropertyChanged(nameof(GeometryLength));
+            }
+        }
+
+        public double LengthFactorX
+        {
+            get => member.LengthFactorX;
+            set
+            {
+                member.GeometryLength = value;
+                OnPropertyChanged(nameof(LengthFactorX));
+            }
+        }
+
+        public double LengthFactorY
+        {
+            get => member.LengthFactorY;
+            set
+            {
+                member.GeometryLength = value;
+                OnPropertyChanged(nameof(LengthFactorY));
+            }
+        }
+
+        public SecondOrderViewModel(ICompressedMember compressedMember)
+        {
+            member = compressedMember;
+        }
+    }
+}