The EUR towers complex is made up of a group of several buildings which, having considerable architectural and urban planning importance, were once redeveloped and transformed into Telecom’s headquarters.
The intervention lot, located in the municipality of Rome, on the northern side of the EUR artificial lake and close to the EUR Fermi metro station, has dimensions in plan of approximately 154 m x 100 m, and a surface area of over 15,500 m2.

The structural project handled by Steel Project Engineering is part of a larger restoration and conservative rehabilitation intervention, in order to achieve seismic and static adaptation to current regulations, while remaining faithful to the original project with interventions targeted on critical structural elements. Our studio, specifically, dealt with the executive and construction project for all aspects concerning the metal structures (for a total of approximately 6,000 tons) and the interfaces with the existing reinforced concrete structures.

The complex consists of five existing buildings, described below:

• Three tower buildings (B, C, C1) whose load-bearing framework is made of reinforced concrete made up of single walls and beams cast on site, generally in slab thickness, measuring approximately 48.50 m x 14.00 m (C and C1) and 38.60m x 27.70m (B);
• A building with a quadrangular plan (A), in reinforced concrete consisting of a frame system, measuring approximately 42.50 m x 42.50 m;
• A building with an elongated plan, two underground floors and four floors above ground (D), in reinforced concrete consisting of a frame system, measuring approximately 14.00 m x 99.00 m.
There are also a series of newly built metal carpentry buildings that fit between the buildings previously described, connecting them to each other:
• Buildings G1, G2, G3, G4, G5, two floors;
• Building E, four floors. This, being the central building, has the role of the central nucleus (represents the hub of the entire complex) and therefore has an irregular shape, having to be inserted between the existing surrounding blocks.

The development operation of the Grand Paris Express public transport network extends over a length of approximately 20 km. It has two underground sections, north (sector 3) and south (sector 1), and one aerial section (sector 2). The aerial section extends for approximately 5.2 km between Gonesse and Tremblay-en-France.
We took care of the executive design of the “Gare du Parc des Expositions” (PEX) and the “Passerelle” which are part of the complex of the elevated section. The station is crossed by the viaduct on which trains circulate and whose structures are independent from those of the remaining structures. The station structure extends over a width of approximately 28 meters (overall) and a length of approximately 181 m (without expansion joints), on 4 levels:
– on the ground floor, technical rooms and a circulation space for the exhibition centre;
– in the basement, circulation spaces and spaces reserved for operator personnel;
– on the mezzanine floor, a public space for the circulation of passengers;
– on the upper level and on a central part 54 m long, the platforms.

On the ground floor, the main structure consists of steel frames made up of straight columns and V-shaped columns approximately 8.50 m high. The columns are connected at the top by a welded composite beam with a double T section. On the mezzanine floor there are independent double portals, made up of straight box-section steel uprights, fitted at the top to compose a Vierendeel scheme.
The roof connects at the level of the platforms and is made up of a series of arches arranged at 9 m intervals, connected by tubular section purlins that support the EFTE roof. The mezzanine floor is made up of a composite steel-concrete sectional floor; on the platform level there is, however, a solid slab in approx.

The “Passerelle” allows you to connect the “Paris Nord 2” commercial area to the north-west and the “Parc International Des Expositions de Paris-Nord Villepinte (PIEX)” to the south-east. It allows crossing the RER tracks and connecting to the future PEX station. The primary horizontal structure consists of a main central beam, continuous across the entire walkway. The typical retaining cross section is a welded composite trapezoidal box, with a width varying from 800 mm to 1200 mm and an overall height of 660 mm. The caisson is widened to span the wide span in the station extension. The T-section or double-T section oars with variable inertia (T-profiles: variable height from 50 to 200mm, double-T profiles: variable height from 700 to 250mm) are grafted onto the central beam and support the orthotropic slab covered with a finish on asphalt. The oars are arranged at an average distance of approximately 2.55m. A series of columns, composed of round tube profiles (D=193.7mm external), act as support for the walkway deck. There are also stairs, support structures for elevators and escalators.

The new emergency room structure of San Giovanni di Dio in Florence will be made of reinforced concrete, and will have plan dimensions of 85m x 53m, and a height of 20m. It is composed of a basement level, with dimensions of 2000 m2, and 3 levels above ground, respectively of 4285 m2 (ground floor and first floor), 3900 m2 (second floor). The third level has a part covered by a metal structure with concentric braces, for a total surface area of 2200m2. The decks will be made using a solid concrete slab in order to allow the correct installation of the hanging systems. The horizontal actions will be assigned mainly to the stair-lift blocks and the reinforced concrete partitions arranged ad hoc in the plan so as not to compromise either the aesthetic or functional aspect. Since the site where the emergency room will be built appears to have a non-excessive design seismic action, a NON-dissipative design was opted for.

The building is divided into two buildings by a structural joint.

Due to the presence of the underground rail link in Milan, most of it is built as a bridge, i.e. supported by two trussed walls with a total span of about 64 m and a section width of 16.6 m.

Each floor develops a pedestrian zone of approximately 1,660 square meters and the building at the top reaches a height of 35 m.

The total weight of the steel structure is about 3,500 t.

Construction design and validation of the pre-design of the metal structures of the Central Building, the Elevation, the rear and side canopies for a new shopping centre in Livorno.

The buildings are either single storey (elevation and rear and side canopies) or multi-storey (Central Building) and cover an area of approximately 9,000 sqm; the weight of the metal structures is about 960 tons.

Optimization of the beam profiles and connection design of the main and secondary structures.

The final detailed design of the structures of the New Romolo Capranica school complex in Amatrice (RI) has been carried out; in particular we designed the College and School Residence buildings. Both buildings have metal structures, rigid decks made with a slab poured on corrugated metal sheet and a mat reinforced concrete foundation.

SCHOOL RESIDENCE
The structure, intended for the accommodation of students, has two floors above ground and has a rectangular plan with external dimensions of 10.00×40.00m and includes eight transverse frames arranged at a constant distance of 6, 60m. The static scheme foresees pendular columns with concentric bracing in the longitudinal direction, while in the transverse direction it has a frame structure.

COLLAGE
The building has on one floor above ground with a plan inscribed in a square of 28.80m side. The height of the building is about 3.90 m. The structural system consists of n. 5 main professions and n. 5 subframes. The distance between the frames is equal to 7.2 m in the longitudinal and transverse direction. The static schema is a three-dimensional frame.

For the calculation of the two structures, a linear dynamic analysis was carried out with a highly amplified local seismic response spectrum considering a structure factor q = 1, and therefore they were designed to maintain an elastic behaviour.

The building is in the same position as the existing pavilion, completely demolished to create an exhibition centre of much larger surface and volume, with a new and astonishing architectural line. The roof’s metal structures have a surface area of 20,000sqm, with a maximum height of 32m.

The roof is made up of a latticework of longitudinal and transverse trussed girders, with a static scheme of a continuous beam; span length 20m+48m+ corbel of 32m. Total frame weight: about 1500t.

The new Italia Congress Center was built in the historic Eur district of Rome, in the area overlooking Viale Cristoforo Colombo between Viale Asia, Viale Shakespeare and Viale Europa.

The design concept can be summarized in the three main buildings into which it is divided:

• the translucent envelope, called “Teca”, consisting of glass curtain walls and roof with metal structure;
• a double skin structure called “Nuvola” placed inside the Teca to represent the essence of the building, an ethereal suspended body in which the most evocative areas of the complex are concentrated and inside which are located: the auditorium for 1850 seats, various restauration points and support services to the auditorium;
• a separate building called “Lama”, the hotel of the Congress Center.

The “Teca” consists of a succession of 6 transversal portals arranged at a distance of 33 m, 70 m wide and 36 m high, connected among each other by longitudinal truss beams on the perimeter and by a grating of Vierendel-type beams that support the glass roof between one frame and another. The overall rectangular plan surface (169 m x 70 m) is approximately 1.2000 square meters and reaches a height of almost 36 m. The roof was made with truss beams with a span of 33 m, longitudinally spaced by 6.25 m and supported by macro-portals. The lattices support the purlins that form the flaps of the glass roof and the lower stabilizing elements of the members; the ropes for hanging the lateral access galleries to the Cloud and the inspection walkways of the roof itself were connected to the bottom part of the longitudinal lattices.

The “Nuvola” (Cloud) is the architectural element that characterizes the project: it is an irregularly shaped volume, with an extraordinary visual effect, covered with a semi-transparent sheet that gives it a vaporous and realistic appearance. The hull is the main structure supporting the complex; it is formed by a lattice of beams (partly trusses and partly with I-section) with highly variable geometry to accommodate the irregularity of the geometric shape of the envelope. The longitudinal and transverse beams are connected together to form a single rigid body, the shape of which resembles that of a ship’s keel. The hull directly supports the floor of Level N3, the floor of the stalls inside the Auditorium, the pillars supporting the decks of Levels N4 and N5 and finally the supporting structures of the Auditorium gallery , the support ring of the Envelope of the Auditorium and the secondary structures that support the decks of Levels N1 and N2.

The design required a skilful work of mediation between the natural needs of constructive simplification and respect for the aesthetic and functional needs of the work. In the roof of the Teca, the choice of the structural profiles of the longitudinal trussed beams and their node connections was fundamental to simplify the structure, respecting the geometric and shaping dimensions imposed by the architectural project and the desire to keep the grip points unchanged for the inspection walkways, the hangings of the Nuvola balconies and the support structures for the glass roof.

The roof was designed to be erected with a specific sequence that envisages the ground assembly of the structures and subsequent lifting of entire portions of the roof by means of strand jacks. This required the re-elaboration of the structural analysis to evaluate the effects of the erecting system and led to an extreme simplification of all the connection details between the elevation structures and the roof members to be completed at height.

Design of main structures, false ceiling supports, structures of suspended volumes.

The metal roof of the new high-speed railway station with dimensions in plan of 365.6 x 60.5 m, main structures with dimensions in plan of 340m x 45.5 m with a centre distance between intrados and extrados of 3.60m, made up of a metal decking of 20,000sqm plan surface connecting the two station buildings; the decking rests, on the area above the tracks, on circular section columns.

The main structures of the roof are made up of a girder of beams: in the longitudinal direction 3 trussed beams spaced by 18m; in the transverse direction 75 lattice girders spaced by 4.47m.

The part of roof in cantilever is supported by a secondary girder and connected to the bottom part of the roof called “interfaccia”.