Part of the remodeling works of the Sants railway station in Barcelona was the redesigning of the arrival yard of the AVE (HSR). The remodeling demanded a series of interventions to be carried out on the roof slab.
This roof slab is a large post-tensioned waffle slab where large openings had to be made for new elevator cores which dimensions required the cutting of 3 or 4 post-tensioned ribs. This operation was carried out by providing the holes with strong perimetric composite frames that allowed redistributing the stresses onto the other ribs. The ribs affected by the modification have also been reinforced by means of bending and shear reinforcement steel consisting of steel plates and connecting bars.
Some of the columns which are supporting the waffle slab had to be removed. Up to 36 m large composite girders have been inserted to redirect their loads to the remaining columns (1200t). Two types of lintels have been designed: composite trusses installed beneath the soffit of the slab and, where the clearance was less than 1m, their struts have been interwoven with the ribs of the waffle slab so to obtain a downstand lintel protruding only partially beneath the soffit of the slab.