2D Member Design & Analysis

May 25, 2021
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OVERVIEW

 

2D Member Type

nGen supports various 2D member types.

So, what is the difference of 2D elements?

 

2D Member Type*All of these are Plate Elements, only categorized by design type.

 

1. Categorized Characteristics of Each Model    

MODEL 1: WALL (Membrance)

1. No meshed element

2. No out-of-plane stiffness

3. Only in-plane stiffness

   

MODEL 2: WALL (PLATE, NOT MESHED)

1. No meshed element

2. In-plane and out-of-plane stiffness

 

MODEL 3: WALL (PLATE, MESHED)

1. Meshed elements in Analysis

2. Identical to plate element

3. Design as wall member

 

MODEL 4: WALL (WALL COLUMN)

1. Identical to MODEL 3

2. Design as Column or Beam member

 

MODEL 5: PLATE

 

MODEL 6: SLAB (PLATE OUT&IN)

1. Meshed elements in Analysis

2. Identical to PLATE element

3. Design as SLAB member

 

MODEL 7: SHELL

 

     

 

2. 2D Member Type: Analysis Result (Deformations)

2d member type_analysis results

 

1. Model 2 is not meshed. Therefore, it has different results from others.

2. Model 3~5, and 7 have the same results because all of them is plate element.

But, only MODEL 6 (Slab) has the different result because "DRILLING DOF" OPTION IS CONSIDERED.

* If checking off this option, MODEL 6 (Slab) will have the same result as other models.

 2d member typeAnalysis settings-1

3. Since MODEL 1 has no out-of-plane stiffness, infinite deformation can occur. So, it is excluded from the comparison.

 

 

 

3. 2D Member Type: Summary

 

 

Model 1

Wall (Membrane)

Model 2

Wall (Not meshed)

Model 3

Wall (Meshed)

Model 4

Wall Column

Model 5

Plate

Model 6

Slab

Model 7

Shell

Member Type Wall Wall

Wall

/ Basement Wall

Wall Column

/ Plate Beam

Plate

Slab

/ Flat Slab

/Footing

Shell
Design Type Wall Wall

Wall

/ Basement Wall

Column (Axial +Flesural) Plate (Axial + Flexural) Slab (Flesural of Out-of-Plane) Not Designed
Mehsed Shape x x o o o o o
Out of Plane Stiffness x o o o o o o
In Plane Stiffness o o o o o o o
Drilling DOF x x x x x o x

 

 

 

4. Drilling Degrees of Freedom 

Degree of freedom for the torsion of in-plane.

 

2d member type_drilling degree

 

      

 

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Young-il Seo
Yeong-il Seo | Principal Structural Engineer

Young-il has over 13+ years of experience in building design, especially high-rise buildings with column reduction analysis, plant structures, pushover analysis, health monitoring, and vibration control projects. Since 2016, he is planning and providing technical supports for midas building products such as midas Gen, nGen, and Design+.

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