Module 15
Steel–concrete composite construction
Two materials made into one member by the connection between them — and a construction stage that is a completely different structure.
What this module covers
- Explain what the shear connection buys, and why it is the whole design
- Determine the effective width of the concrete flange
- Calculate the plastic moment with full shear connection
- Size the shear connectors from equilibrium
- Explain why partial shear connection is usually the sensible answer
- Check the construction stage, and say why deflection must be added in two parts
Lessons
What connecting a slab to a beam actually buys, and how the studs that do it are sized.
Start lesson →Why 60% of the studs gives 80% of the moment, and why the beam before the concrete sets is a different structure.
Start lesson →
Module checkpoint
Check what you have taken in
6 questions
Question 1
A composite beam spans 10.0 m with beams at 2.4 m centres. What is the effective flange width, in mm?
Question 2
In a composite beam, where should the plastic neutral axis ideally fall?
Question 3
A beam has Ma = 600 kNm and MRd,full = 1100 kNm. What moment does 70% shear connection give, in kNm?
Question 4
A steel section of 12,000 mm² in S275 acts compositely. What is Na, in kN?
Question 5
An unpropped composite beam deflects 20 mm under wet concrete. What happens to that deflection?
Question 6
An unpropped beam has a construction moment of 159 kNm and a bare steel capacity of 533 kNm. What is the utilisation?