Abaqus Cae

EXAMPLE: CREATING A MODEL OF AN OVERHEAD HOIST WITH ABAQUS/CAE

The instructions for the examples discussed in this manual will focus on using the Model Tree to access the functionality of ABAQUS/CAE. Menu bar actions will be considered only when necessary (e.g., when creating a finite element mesh or postprocessing results).

2.3

Example: creating a model of an overhead hoist withABAQUS/CAE
This example of an overhead hoist, shown in Figure 2–5, leads you through the ABAQUS/CAE modeling process by using the Model Tree and showing you the basic steps used to create and analyze a simple model. The hoist is a simple, pin-jointed framework that is constrained at the left end and mounted on rollers at the right end. The members can rotate freely at the joints. The frame is preventedfrom moving out of plane. A simulation is first performed in ABAQUS/Standard to determine the structure’s static deflection and the peak stress in its members when a 10 kN load is applied as shown in Figure 2–5. The simulation is performed a second time in ABAQUS/Explicit under the assumption that the load is applied suddenly to study the dynamic response of the frame.

1m

1m

1m

Allmembers are circular steel rods, 5 mm in diameter.

1m 10,000 N

1m

Material properties
General properties: 3 ρ = 7800 kg/m Elastic properties: 9 E = 200 × 10 Pa ν = 0.3
Figure 2–5 Schematic of an overhead hoist.

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EXAMPLE: CREATING A MODEL OF AN OVERHEAD HOIST WITH ABAQUS/CAE

For the overhead hoist example, you will perform the following tasks:

• • • • • • • •

Sketch thetwo-dimensional geometry and create a part representing the frame. Define the material properties and section properties of the frame. Assemble the model. Configure the analysis procedure and output requests. Apply loads and boundary conditions to the frame. Mesh the frame. Create a job and submit it for analysis. View the results of the analysis.

A Python script for this example is provided in“Overhead hoist frame,” Section A.1, in the online version of this manual. When this script is run in ABAQUS/CAE, it creates the complete analysis model for this problem. Run the script if you encounter difficulties following the instructions given below or if you wish to check your work. Instructions on how to fetch and run the script are given in Appendix A, “Example Files.” As noted earlier, it isassumed that you will be using ABAQUS/CAE to generate the model. However, if you do not have access to ABAQUS/CAE or another preprocessor, the input file that defines this problem can be created manually, as discussed in “Creating an input file,” Section 2.3 of Getting Started with ABAQUS/Standard: Keywords Version.

2.3.1

Units

Before starting to define this or any model, you need to decidewhich system of units you will use. ABAQUS has no built-in system of units. All input data must be specified in consistent units. Some common systems of consistent units are shown in Table 2–1. Table 2–1 Quantity Length Force Mass Time Stress Energy Density SI m N kg s Pa (N/m ) J kg/m
3 2

Consistent units. US Unit (ft) ft lbf
3

SI (mm) mm N tonne (10 kg) s MPa (N/mm ) mJ (10−3 J) tonne/mm
3 2US Unit (inch) in lbf lbf s2 /in s psi (lbf/in2 ) in lbf lbf s2 /in4

slug s lbf/ft
2

ft lbf slug/ft
3

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EXAMPLE: CREATING A MODEL OF AN OVERHEAD HOIST WITH ABAQUS/CAE

The SI system of units is used throughout this guide. Users working in the systems labeled “US Unit” should be careful with the units of density; often the densities given in handbooks of material propertiesare multiplied by the acceleration due to gravity.

2.3.2

Creating a part

Parts define the geometry of the individual components of your model and, therefore, are the building blocks of an ABAQUS/CAE model. You can create parts that are native to ABAQUS/CAE, or you can import parts created by other applications either as a geometric representation or as a finite element mesh. You will...