1. Marco Andreini, Raul Fernandez Ortega, Richard Francis Morton
DGS/SEE - GS/SE
Report on the preliminary inspections to the Raised floors of sps buildings
Marco Andreini, Raul Fernandez Ortega, Richard Francis Morton
EDMS No

2. Outline:
Structural defects detected at BA1 that caused the failure of a part of the false floor
Preliminary inspection at BA6 to detect the presence of similar defects and load patterns
Plan for the inspections and the structural safety assessment before the YETS 2015/2016
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

3. The Structural failure occurred at the false floor at BA1 (03/09/15)
The structural failure occurred to the false floor located at the ground floor of the Building BA1 and supporting an electrical converter has been caused by the self-weight of such an equipment.
The structure consisted in a steel frame grid, composed of H-profiles arranged in a single way and restrained to an adjoining concrete slab by means of an L profile.
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

4. BA1: Structural joint between the steel false floor and the concrete slab
The L-profile has been anchored to the slab by bolts (diameter ~= 18 mm), having a total length of roughly 100 mm, located on the vertical web and, in some points, with additional plates welded upon the horizontal flange.
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

5. 1 BA1: Description of the joint parts collapsed
The failure has been generated by the loss of bearing capacity of the L-profile connection 1
The failure occurred in a low tensile strength of the concrete surrounding one of the bolts
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

6. 2 BA1: Description of the joint parts collapsed
The failure has been generated by the loss of bearing capacity of the L-profile connection 2
Rupture of the fillet weld between the additional steel plate and the horizontal flange of the L profile
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

7. BA1 Comparison with existing drawings
There is a perfect matching with the details from the drawings of the original structural project.
Bad design or excessive load?
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

8. Reinforcing intervention was carried out (by whom
Reinforcing intervention was carried out (by whom?) in the past (before Sep, 3rd) ?
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

9. Are there any other similar situations in the SPS buildings (BAs)?
Issue rised
Are there any other similar situations in the SPS buildings (BAs)?
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

10. ! BA6 – BA1 Comparison with existing drawings Same structural detail
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

11. BA6 Inspection: Comparison with the load pattern of BA1
What we understood:
We have the same load severity in BA1 and BA6!
The limit 500 kg/m2 indicated is WRONG!
BA6
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

12. Perfect matching between the drawings and the real joint connection
BA6 Inspection: Comparison with existing drawings
Perfect matching between the drawings and the real joint connection
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

13. SAME detail + SAME load = SAME failure
BA6 Inspection: Comparison with the structural details of BA1
BA1
BA6
SAME detail + SAME load = SAME failure ?!
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

14. BA6: Moving materials and equipment strategy
Moving by Pallet truck (Transpalette) allowed due to the presence of additional bridging joists
BA6
Moving by Crane (Pallet truck “Transpalette” forbidden)
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

15. Actions
Plan for the inspections and the structural safety assessment before the YETS 2015/2016
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

16. Actions: Results to be obtained before the YETS 2015/2016
Investigation of the existing status
Original drawings of the steel frames;
Map of the load patterns applied on the raised floors.
Description of the status of the structural elements.
Results of the inspections;
Structural safety assessment of the steel frames
Map of the false floors indicating: accessible, accessible with (temporary) measures/interventions, not accessible areas without further investigation.
Plan of interventions for dangerous situations.
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

17. Actions: role of the various working units
GS-SE (Synaxis): Etudes de la structure métalliques des faux plancher et plans d’exécution.
HSE: Contrôle et validation des notes de calculs.
GS-SE (Synaxis): Plans d’atelier.
EN-MEF: Réalisation- exécution des travaux.
Plan of inspections (should be…)
BA3-( ) - Done
BA5-( ) - Done
BA7-( ) - Done
BA1-( ) - Done
BA2-( )
BA6-( )
BA4-( )
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

18. Preliminary results of the inspections: BA3
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

19. Preliminary results of the inspections: BA5
Pillar
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

20. Preliminary results of the inspections: BA7
Additional elements (beams and pillars) are present herein.
Pillars
Beam
Pillar
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings

21. The load severity of BA1 is similar to all the BAs
Conclusions
The structural detail failed at BA1 seems to be recurrent even in almost all the BAs
The load severity of BA1 is similar to all the BAs
Some shoring intervention are required to allow the maintenance of the electrical component underneath some areas of the raised floor at BAs
A plan for the access underneath the raised floors of the BAs will be drawn before the YETS
Materials and equipment movements at BA6 are allowed using pallet trucks and crane in selected areas
EDMS No
Report on the preliminary inspections to the raised floors of SPS buildings