P. Piroozan

ME 406A

Finite Element Analysis Activity

California State Polytechnic University, Pomona

Summer 2012

Activity # 5 – NEiNastran - FEMAP

Solving Frame Problems Using NEiNastran and FEMAP

1. Solve problem 5.36 on page 306 of your textbook using NEiNastran - FEMAP.

2. A plane frame consists of a series of beam elements rigidly connected to each other.

The plane frame element is a combination of the two-dimensional axial force element

and the beam element. It has a horizontal and vertical displacement at each node plus

a rotation. The steps that you need to take to solve a frame problem are similar to the

steps that you took to solve the beam problem in the last week’s activity. Required

input data to create the frame geometry, choose the appropriate element type, apply

boundary conditions and loads, and obtain results are briefly described below:

Enter FEMAP and Create the Nodes: Model Node … (enter the

coordinates of the nodes).

Define the Material: Model Material … (enter 210E9 Pa for Youngs

Modulus).

Define the Model Property: Model Property … (for the element type select

the Beam radio button). In Nastran, Beams are used to model the beam and

frame problems. For the cross section of the bar use rectangular with a height

of 0.346 m and width of 0.029 m. For the Orientation Direction (y), click on

the radio button Up.

Define the Elements: Model Element … (for the Property select 1..BEAM

Property - Rectangular Bar). For the Element Orientation Vector, for the Tip

enter (-1, 0, 0) for element 1, and (0, 1, 0) for element 2.

Define Displacements: Model Constraint Nodal … (for node 3 use

Fixed to constrain the translation and rotation in all directions. For the DOF

of node 5 check TY and TZ to constrain the translation in the Y and Z

directions, respectively).

Define Loads (Force): Model Load Nodal … (define the loads, and

then save your model).

Solve the problem: File Analyze …

Plot results (deformed and undeformed shape): View Select …

Get nodal displacements: List Output Results to Data Table …

P. Piroozan

Get stress in each element: List Output Results to Data Table

Elemental …(For the Output Vectors, select: BEAM S END A-MAX, BEAM

S END A-MIN, BEAM S END B-MAX, BEAM S END B-MIN, BEAM S-

MAX, BEAM S-MIN, and BEAM VON MISES STRESS).

Get reaction forces at supports: List Output Results to Data Table

Nodal …(For the Output Vectors, select: T1 SPC FORCE, T2 SPC FORCE,

T3 SPC FORCE, R1 SPC MOMENT, R2 SPC MOMENT, and R3 SPC

MOMENT).

Material to Hand in for a Grade

1. Print a plot of the deformed and undeformed shape of the frame with contour of the

nodal displacements.

2. Print a Table showing nodal displacements, maximum and minimum stresses in each

element, and the reaction forces at the supports.

3. Is overall equilibrium achieved in the solution? (Draw a free body diagram of the

frame and show that equilibrium equations are satisfied).

Note: The title of your computer run should include: your name, course number/title,

assignment number, and date. Show all calculations used to answer questions. Submit

the above information in a brief memo format to Dr. Piroozan by the end of the lab

period. For those who do not finish the assignment during the lab period, the assignment

is due at the beginning of the next week’s lab.