Modelling slabs using bar and two-dimensional finite elements|

VOLUME A
The art of construction and detailing
Introduction
The structural frame
- Introduction
- Structural frame elements
  - Columns
  - Beams
  - Slabs
  - Staircases
  - Foundation
- STRUCTURAL FRAME LOADING
- BEHAVIOR OF THE STRUCTURAL FRAME
  - The behavior and reinforcement of a slab
  - Behavior and reinforcement of beams and columns
Construction methods
- The materials
- The moulds
- Thermal insulation of structural elements
- Concrete
- The steel
- Reinforcement specifications of antiseismic design
- Industrial stirrups - stirrup cages
- Standardized cross-sections of reinforced concrete elements
Reinforcement
- Columns
- Shear walls
- Composite elements
- Beams
- Slabs
- Staircases
- Foundation
Quantity surveying
- Estimation of the concrete’s quantity
- Estimation of the formworks’ quantity
- Estimation of the spacers’ quantity
- Estimation of the reinforcements' quantity
- Total estimation of the materials’ quantities
- Optimization of the reinforcement schedule
- Estimation of the structural frame’s cost
- Electronic exchange of designs - bids - orders
Detailing drawings
- General
- The drawings’ title block
- Carpenter’s drawings
- Steel fixer’s drawings
Tables
- Table 1
- Table 2
- Table 3
Drawings
- Carpenter’s drawings
- Steel fixer’s drawings
Model (exemplary) construction

« Modelling frames using two-dimensional finite elements The frame function in regions of columns »

Modelling slabs using bar and two-dimensional finite elements

Finite element method assists in defining slabs functionality with significant accuracy. However, in order for the result to represent the reality, suitable assumptions should be adopted. The effects of the following factors are examined thoroughly in Annex A:

1) The frame function of slabs at the areas near columns

2) The vertical displacement of beams

3) The torsional stiffness of beams

The above factors affect the behavior of slabs. In order to investigate this effect, a simple structure is being modelled in two ways:

(i) Using bar finite elements, according to which the slab is modeled as a grid of main and secondary joists, without the assumption of rigid bodies.

(ii) Using two-dimensional triangular finite elements.

The summary of Annex A is presented below:

Figure 3.3.6-1: The structure of project <B_331> of the related software (columns sections 400/400, beams sections 300/500, slab thickness 170 mm)

Figure 3.3.6-2: Slab modelled with bar finite elements and the displaced structure (project <B_336>)

Figure 3.3.6-3: Slab modelled with triangular finite elements (project <B_336>) (a=beam-slab common deflection curve)

« Modelling frames using two-dimensional finite elements The frame function in regions of columns »