Inside “CAPSULA” there is P-TREX engineering and P-TREX GRP profiles

The challenge

A collaboration between XPLAB, ALMAG, and P-TREX has resulted in a project that is unprecedented in terms of design, engineering, and materials used. The project is called “CAPSULA” (Controllo Avanzato Pressa, Sala Unità Lavorativa, Almag), designed by XPLAB for ALMAG and consists of the construction of a state-of-the-art structure: it is a cabin with an advanced system integrated into the Operators’ work environment, using the most advanced technologies and the most advanced materials including, in particular, the pultruded profiles in GRP of P-TREX.

The futuristic design of the structure is expressed through its formal aesthetics, but more importantly, through its overall integrity as a comfortable, technologically advanced, and functional working environment for the needs of operators, compared with traditional prefabricated cages used for machine control. Equipped with light and air control devices to improve comfort, its main features are sound insulation, which is almost total, also guaranteed by the presence of structural pultruded profile panels, and maximum visibility from the inside onto the production lines. This is especially evident from the upper floor of the cabin, which is used as a meeting and conference room, a special place that boasts an enviable view of the factory from above.

In this project, the challenge was approached on several levels: acting on an existing frame structure, installing a new solution in a space where the possibility of movement was limited, and ensuring harmony along with an unrestricted view in a complex geometric layout. In addition, the design and verification of all the constituent elements of the structure were based on the national technical regulations, taking into consideration the actions burdening it, actions of a static and seismic type.

P-TREX’ solution

The load-bearing structure of the work is a mixed type, namely steel-GRP. The design envisions a static scheme of the structure represented by a frame with bracing; the choice, therefore, to adopt a hybrid construction type was due to the client’s requirements to have a structure that would be two stories in height (tot H = 6.50 m) and three fronts of the structure would have to be free of excessively bulky elements that would obstruct the view to the outside of the cabin.

On the mezzanine floor (+0.70 m from the existing industrial flooring) is the control booth while on the upper floor (+3.60 m from the industrial flooring) is a meeting room. The outline of the stacked surface on the second floor is larger than that of the ground floor; in particular, there is an overhang on the front of the cabin, which will later allow the provision on the ground floor of sloping fixtures whose shape considerably reduces reflections.

Given the need to ensure an unobstructed view for operators from inside the control booth to the outside, it was decided to use steel uprights of tubular section, especially toward the front of the structure; these rectangular tubes are small in size in order to reduce the visual impact.

The decks are made entirely of GRP with beams coupled with cross-beams to ensure maximum stability; there are floor braces at the floor slab, while the overhang at the front is supported by tie rods in GRP. The walking surface was made of self-supporting aluminium panels that will be attached directly on the structure in GRP.

The mechanism resistant to the horizontal actions of the structure is provided by the steel bracing placed on the upper floor and the full-height braced wall at the back of the cabin made of GRP. The connections between these elements were made using S275 steel metal plates and galvanised steel bolted joints.

The interior of the control cabin deserves special mention: equipped with a computerised console and great visibility from the windows, it was necessary to have as dark an interior environment as possible. Therefore, the internal pultruded profiles were provided in matte black paste to emphasise the contrast with the exterior and thus increase visibility.

Advantages of GRP

The advantage of having used the composite material of P-TREX comes into play here. The lightness of GRP, its excellent mechanical properties, and ease of installation, made it possible to be able to design and build the upper floor and ensure support for the cantilever: thus making this project innovative from a structural viewpoint as well.

Material in GRP is characterised by lightness and modularity, that are only two of the multiple benefits of its use, both when used as a single protagonist and when combined with traditional materials in a hybrid structure. Thanks to these advantages, easy installation is guaranteed, as well as time and costs. Despite its considerable size, the structure was installed in just a few hours.

Another major long-term advantage, which becomes one of the most important factors from an economic point of view, is that the products are highly resistant to corrosion and do not require maintenance. Unlike traditional materials, it is not necessary to carry out any periodic internal/external painting and continuous studies and tests have established that the aging of this material is minimal.

Compared with a structure made entirely of traditional materials such as steel, GRP products are distinguished by their durability over time.