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1. Truss

Material parameters:

E = 200109 N/m2, = 0.3

Circular steel rods, diameter 5 mm

PREPROCESSOR: Start ABAQUS /CAE Create Model Database RC on Model-1 Rename Rename Model-1 to: Model_Truss OK Part (DC) Name: Truss, Modeling space: 2D Planar, Type: Deformable, Shape: Wire (Planar),

Approximate size: 4.0 Continue

Definition of geometry in the sketcher:- rectangle (draw any)

- delete perpendicular constraints in the rectangle;

- constrain horizontal edges as parallel;

- dimension lower edge 2.0, upper 1.0; left and right (oblique dimension) 1.0; (Fig. 1)

- create two lines: upper left corner any point on the lower edge, that point upper right corner(Fig. 2)

- split the lower edge at the intersection point

- constrain the two parts of lower edge: same length (Fig. 3)

Leave the sketcher when the sketch is complete (Sketch the section for the wire Done)

(Fig. 1) (Fig. 2) (Fig. 3)

Materials (DC) Name: Steel, Mechanical Elasticity Elastic: Youngs Modulus = 200109,Poissons ratio = 0.3 OK

Sections (DC) Name: Rod Category: Beam Type: Truss Continue Material: Steel, Cross-sectional area: enter the value for the surface area (calculate the surface using the equation: A= r

2 ; Tip:

use to calculate) OK

Assign section to the truss: expand the Parts container (LC on + sign) expand Truss SectionAssignments (DC) select the whole truss Done select the Rod section OK

Expand Assembly container Instances (DC) select Truss Dependent (mesh on part) OK

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Configuring analysis: Steps (DC) Name: Loading, Procedure type: Linear perturbation Static,Linear perturbation Continue Description: e.g. 10 kN central load OK

Boundary conditions definition:1. At the left corner: BCs (DC) Name: Fixed, Step: Loading, Category: Mechanical, Type:

Displacement/Rotation Continue select the lower left corner by clicking it Done

U1=U2=0 OK

2. At the right corner: BCs (DC) Name: Roller, Step: Loading, Category: Mechanical, Type:Displacement/Rotation Continue select the lower right corner by clicking it Done U2=0

OK

Load definition: Loads (DC) Name: Central Force, Step: Loading, Mechanical, Concentrated force Continue select the mid point of the lower edge by clicking it Done CF2 = -10000 OK

Mesh definition: expand Parts expand TrussMesh (DC):1. Assign element type ( ) select the whole truss Done Element Library: Standard, Geometric

order: Linear, Family: Truss (the selected element is T2D2) OK

2. Seed part ( ) Approximate global size: 1.0 OK3. Mesh part ( ) OK to mesh the part? Yes

Analysis Job: Jobs (DC) Name: Truss, Source: Model (select the right model, if not already selected) Continue OK

SOLVER:

expand Jobs Truss (RC) SubmitPOSTPROCESSOR (Visualization module):

expand Jobs Truss (RC) Results (Common Options):

Basic Deformation scale factor Auto compute or Uniform with Value (user defined) Labels Show element labels Show node labels Show node symbols

Plot Contours on Deformed Shape ( ) Main menu Results Field Output U (Displacement) Magnitude

Allows multiple plot states (deformed and undeformed state) Main menu Results Field Output S (Stress) Mises or S11 Main menu Tools Query Visualization module Queries: Probe values (DC) Check S, S11

(determine internal forces)

Recalculate the model with beam elements:

LC on Model (preprocessor) (RC) on Model_Truss Copy modelCopy Model_Truss to: Model_Frame (name of the new model) expand the model tree of Model_Frame Profiles (DC) Name: Beam_profile, Shape: Circular Continue r = 0.0025 OK Sections (DC) Name: Beam_section, Category: Beam, Type: Beam Continue Profile name:

Beam_profile, Material name: Steel OK

Reassign the section Beam_section to the model Module: Property Main menu: Assign Beam Section Orientation select the whole structure

Done accept the proposed vector as approximate n1 vector OK (Tip: Assign Tangent)

Remesh the part with quadratic beam element B22. Try a mesh with more beam elements. Recalculate and compare the results. Conclusions?