Construction Cost Estimating


How to design two-way slab through Finite Element Method

Definition of two way Slab: If the proportion of long span to short span is under 2, then the slab is called a slab that stretches in two directions or two-way slab.


1. Select layout and type of slab. Type of slab is greatly influenced by architectural and construction considerations.
2. Select slab thickness to manage deflection. Also, examine if thickness is sufficient for shear.
3. Opt for design method.
Equivalent frame method- Apply elastic frame analysis to calculate positive and negative moments.
Direct design method - Apply coefficients to calculate positive and negative slab moments.

4. Work out positive and negative moments in the slab.
5. Define distribution of moments over the width of the slab on the basis of geometry and beam stiffness.
6. Allocate a portion of moment to beams, if existing.

7. Design reinforcement for moments from steps 5 and 6. Steps 3-7 should be performed for both principal directions.
8. Verify the stability of shear at the columns.

Link for Download Two-way slab design through Finite Element Method Spreadsheet

How to design two-way slab through Finite Element Method
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