Presentation from IABSE 2013

1. CONCRETE SLABS UNDER A
COMBINATION OF LOADS IN
SHEAREva Lantsoght, Cor van der Veen, Joost Walraven
Eva O.L. Lantsoght, Cor van der Veen
Joost C. Walraven
Delft University of Technology

2. 2
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
HYPOTHESIS OF SUPERPOSITION
• Concentrated load over effective width
• Distributed loads over full width
• Sum of stresses with combination of loads ≥ stress
with concentrated load only

3. 3
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
SUPERPOSITION TESTS(1)
• 2nd series experimental work:
• Slabs under combined loading
• Line load
• Preloading
• 50% of shear strength slab strips
• Concentrated load
• loading until failure
• 26 experiments
• 8 specimens
• Superposition hypothesis valid?

4. 4
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
SUPERPOSITION TESTS (2)

5. 5
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
SUPERPOSITION TESTS (3)

6. 6
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
VERIFICATION OF THE HYPOTHESIS
combination line conc   
'
,
3
'
,
c combi
c conc
f
f

7. 7
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
FLEXIBLE VERSUS RIGID SUPPORTS
(1)
support of steel bearings
elastomeric bearings

8. 8
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
FLEXIBLE VERSUS RIGID SUPPORTS
(2)
• Flexible supports: more ductile failure mode
• Distance a is same, av different

9. 9
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
FLEXIBLE VERSUS RIGID SUPPORTS
(3)
av as face-to-face distance av as given by code
β = av/2dl with av distance between
edge of load and edge of support
(or centre of bearing where flexible
bearings are used)

10. 10
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
CONCLUSIONS
• Superposition valid
• av = face-to-face distance,
also for flexible supports

11. 11
Concrete Slabs under a Combination of Loads in Shear
Eva Lantsoght, Delft University of Technology
Delft
University of
Technology
Contact:
Eva Lantsoght
E.O.L.Lantsoght@tudelft.nl
+31(0)152787449
14/06/2013 – 12h: PhD Defence at Aula TU Delft