CSI ETABS - 03 - Meshing for Slabs, Walls ,beams and Columns | Part 6

In this video, how to prepare model for analysis regarding meshing in slabs ,walls , beams and columns.

FEM (MESHING) :-
1) FEM Definition: The finite element method, is a numerical method for solving problems of engineering and mathematical physics.

2) MESH: is a network of line elements and interconnecting nodes used to model a structural system and numerically solve for its simulated behavior under applied loading.First, computational techniques create an analytical model by populating the material domain with a finite-element mesh in which each line element is assigned mathematical attributes (axial, bending, shear, and torsional stiffness, etc.) which simulate the material and geometric properties of the structural system. The system is then restrained within boundary conditions and subjected to mechanical or thermal loading. Numerical solution may then resolve structural stresses, strains, and displacements.

3) Automatic and manual meshes will produce comparable results. Manual meshing is much more time consuming. Further, the sophisticated automatic-meshing procedures of CSI Software may even produce a more efficient and reliable mesh..

4) In Finite Element analysis the size of mesh is critical. The size of the mesh is closely related to the accuracy and number of mesh required for the meshing of the element.

5) Fine and Coarse Mesh If we do fine mesh , we get better results and it will take more time to perform analysis
But If we do coarse mesh, then FEM will give less accurate results and it require less time to perform analysis.

6) Tips:
Mesh size should be decreased through a series of analysis iterations until two subsequent sets of results are similar, or until the balance between accuracy and analysis time are acceptable according to engineering criteria.

After performing different analysis, 3ft (1m) mesh size is enough to get better results

7) Use the Shell Assignment - Floor Auto Mesh Options
The use of Rectangular meshing for the default settings is specified using the Analyze menu --) Automatic Mesh Settings for Floors command.

a) Select the shell object(s) for which the mesh is to be revised or marked so as not to be meshed at all.

b) Click the Assign menu --) Shell --) Floor Auto Mesh Options command to access the Shell Assignment - Floor Auto Mesh Options form.

Select the appropriate option(s):

b1)Default option.: This is the setting that will be used on all shell floor object meshing unless another choice is specified on this form. Following are the three categories of shell objects used to determine the default settings, which one to use depends upon the properties of the shell object and its orientation.

i) Horizontal decks and planks use the auto cookie cut at beams and walls meshing option. Because these types of floor objects do not have out-of-plane stiffness, vertical loads are transformed from the floors onto the beams and walls using tributary area algorithms.

ii) Horizontal slabs and layered slabs use the automatic rectangular meshing as specified on the Automatic Mesh Options (for Floors) form. For slabs with membrane behavior, vertical loads are transformed to vertical supports using tributary area algorithms.

iii) Inclined floors use the no auto meshing option, i.e., they are not internally meshed and remain as a single element equivalent in size to the floor object.

iv) Advanced - Modify/Show Auto Rectangular Mesh Settings button. Click the button to display the Automatic Mesh Options (for Floors) form. Use the form to specify how and where the object will be meshed and the approximate maximum size of the mesh when floor-type shell options use auto meshing.

Reference CSI Technical Knowledge Base

********************************************************************
To Build a relationship, Please CLICK THE SUBSCRIBE BUTTON..

1-Download ETABS Software Latest Version
https://civilmdc.com/category/civil-b...

2-PASSWORD
www.civilmdc.com

If you face any difficulty...... Please Feel free to contact.

Contact Details
www.civilmdc.com
Professional Trainers
Email ID: [email protected]

#Meshing #Etabs #FEM