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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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-(26-11-2015) - Done BA5-(30-11-2015) - Done BA7-(30-11-2015) - Done BA1-(4-12-2015) - Done BA2-(4-12-2015) BA6-(8-12-2015) BA4-(8-12-2015) EDMS No Report on the preliminary inspections to the raised floors of SPS buildings

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

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

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

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