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2. Skew plate

Material parameters: Geometry: Load:E = 30 109 N/m 2, = 0.3 Thickness t = 8 mm; a = 1 m; b = 0.4 m; = 30 p = 20 kPa

PREPROCESSOR:

Start ABAQUS /CAE

Create Model Database RC on Model-1 Rename Rename Model-1 to: Skew_Plate OK Part (DC) Name: Plate, Modeling space: 3D, Type: Deformable, Shape: Shell, Type: Planar,

Approximate size: 4.0 Continue Definition of geometry in the sketcher:

one of the possible solutions: draw any rectangle, delete perpendicularand horizontal constraints, constrain the vertical lines to remain vertical,constrain the bottom and top edge to remain parallel, dimension leftedge to be 0.4, dimension the horizontal distance between the cornerpoints belonging to the lower edge to be 1.0, dimension the anglebetween the left (vertical) and bottom edge to be 60

Leave the sketcher when the sketch is complete (Sketch the section for the planar shell Done) (Module: Part) Partition the plate: (DC) on part Plate in Model Tree to make it current

- Partition Face: Shortest Path Between 2 Points select the midpoints of theskewed edges Create PartitionCreate assembly (create dependent instance of the plate)

eous shell section with thickness t

coordinate system:

Define material Define homogen (partition) Define local material directions:

Define a rectangular datum Create datum CSYS: 2 Lines Name:

ssign Material Orientation select the plate

Assmbly (DC) on Sets LeftEdge select the left edge

Local_direction, Coordinate System Type: Rectangular Continue select bottom long edge to bethe x-axis and the right edge to be in the xy-plane

From the main menu of the Property module ADone select the new Datum CSYS select the Axis-3 for approximate shell normal noadditional rotation (i.e. 0.0) OKign the section to the part Skew_Plate

Create geometrical Sets: expand the AsseDone; using the same procedure create sets: RightEdge and MidSpanDefine a static, linear analysis step named Loading

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Define history output request: (DC) on History Output Requests Name: H-Output-2 (default name),Step: Loading Domain: Set: MidSpan, Frequency: Every n increments, n: 1, select from listdisplacement U3 OK

Define boundary conditions: Assign ENCASTRE boundary conditions to the LeftEdge The RightEdge has all degrees suppressed except for the U1 direction in the above defined datum

CSYS. Define the boundary conditions with respect to the datum CSYS. Define the Load: Loads (DC) Name: Pressure, Step: Loading, Category: Mechanical, Types for selected

step: Pressure Continue select the whole plate Done choose the side for the shell or internalfaces: Brown (choose the top side of the plate, thats the side the pressure acts on) Distribution: Uniform,Magnitude: 2.0E4, Amplitude: (Ramp) OK

Define the mesh: Assign quadratic shell element (S8R, shell with 8 nodes, reduced integration) to the whole part Seed part using a global element size of (try different values: 0.2; 0.15; 0.1) Assign mesh controls ( ), for all area segments: specify structured mesh technique Mesh the part

Define job

SOLVER: Submit job to calculation

POSTPROCESSOR (Visualization module) :

Display the element normals: Main menu Options Common (or use ) Normals Check Show normals, On elements OK (or Apply) (check if all normals point in the same direction)

Plot symbols ( ) Print the reaction forces and moments at supports in a file:

in Common Options check Show node labels and Show node symbols

turn off contour plot mode ((RC) on or ) (if contour plot mode is active) expand Node Sets, select LeftEdge and RightEdge, (RC) Replace (only nodes on the edges, where

the boundary conditions are defined, are shown) in the main menu Report Field Output card Variable: Position: Unique Nodal, check RF1,

RF2, RF3 under Reaction force and RM1, RM2, RM3 under Reaction moment; card Setup: Name:Skew_Plate.rpt, leave default settings as they are

comment the results in the file.

Assess the results (is the assumption of linearity justified?), find the largest stresses and displacements .

Recalculate the case with a finer mesh, check the convergence (linear element, quadratic element,different global element size).