Flat slabs

A procedure for carrying out the detailed design of flat slabs is shown in Table 1 below.

This assumes that the slab thickness has previously been determined during conceptual design. Concept designs prepared assuming detailed design would be to BS 8110 may be continued through to detailed design using Eurocode 2.

More detailed advice on determining design life, loading, material properties, methods of analysis, minimum concrete cover for durability and bond, and control of crack widths can be found in Chapter 2 of How to Design Concrete Structures using Eurocode 2.

Table 1: Flat slab design procedure

Task

Further guidance 

 

Publication

Standard

Determine design life

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

NA to BS EN 1990 Table NA.2.1

Assess actions on the slab

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

BS EN 1991 (10 parts) and National Annexes

Determine which combinations of actions apply

How to Design Concrete Structures to Eurocode 2 - Chapter 1: Introduction to Eurocodes

NA to BS EN 1990 Tables NA.A1.1 and NA.A1.2 (B)

Determine loading arrangements

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

NA to BS EN 1992–1–1

Assess durability requirements and determine concrete strength

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

BS 8500:2006

Check cover requirements for appropriate fire resistance period

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started and Table 2

Approved Document B. BS EN 1992–1–2: Section 5

Calculate min. cover for durability, fire and bond requirements

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

BS EN 1992–1–1 Cl 4.4.1

Analyse structure to obtain critical moments and shear forces.

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started and Table 3

BS EN 1992–1–1 section 5

Design flexural reinforcement for column strips and middle strips both ways. Design for full load in both directions.

How to Design Concrete Structures to Eurocode 2 - Chapter 7: Flat slabs and Figure 1

BS EN 1992–1–1 section 6.1,

Annex I

Check deflection

How to Design Concrete Structures to Eurocode 2 - Chapter 7 : Flat slabs and Figure 3

BS EN 1992–1–1 section 7.4

Check punching shear capacity

How to Design Concrete Structures to Eurocode 2 - Chapter 7 : Flat slabs and Figure 6

BS EN 1992–1–1 section 6.4

Check spacing of bars

How to Design Concrete Structures to Eurocode 2 - Chapter 2: Getting started

BS EN 1992–1–1 section 7.3

Check resistance to moment transfer from column to slab

 

BS EN 1992-1-1 Annex 1 1.2(5)

Further guidance is given in Concrete Society Technical Report No 64: Guide to the Design and Construction of Reinforced Concrete Flat Slabs.