Marraffa took care of the transport of over 80 items for the assembly of the TBM "Barbara" at the Varna (BZ) construction site for the Dolomiti Webuild Implenia Consortium.
The TBM (Tunnel Boring Machine), which departed from China and landed at the port of Marghera (VE), was transported entirely by road and, once assembled, will be ready to excavate the continuation tunnel of the Brenner Base Tunnel for the upgrading of the Munich-Verona railway.
In particular, the most demanding transports involved:
- a 120-ton Cutterhead on a 42.5 m long and 6.7 m wide convoy on 20 axles (4 tractor and 16 semi-trailer);
- a 120-ton Segment Top-Bottom of Front Shield on a convoy 39 m long and 5 m wide on 18 axles (4 tractor and 14 trailer);
- a 130-ton Main Drive on a 42.5 m long and 6.4 m wide convoy on 20 axles (4 tractor and 16 trailer), the heaviest component transported.
Elements which, once assembled, form the drilling head of the TBM.
The project for the delivery of the “Barbara” TBM was very complex and required a careful preliminary study to identify the technical solution necessary for its construction.
The complexity derives both from the geometric variety of the items (82 to be exact), and from the important dimensions and weights of the most relevant elements. In total, the sum of the weights of all the items transported is approximately 2,000 tons.
To address these difficulties, the following steps were required:
- study and definition of loading schemes to establish the type of means to be used for each individual item;
- identification of technically and geometrically admissible routes with the current state of the infrastructures of our territory;
- transport organization and operational planning.
We were the only ones to offer the customer an "All by road" transport solution from Marghera (VE) (port of docking for ships from China) to the Varna shipyard (BZ). The transports were all carried out by road without the need to foresee transhipments and river/maritime sections by boarding on barges.
These solutions were possible thanks to the wide range of means available, which allow the transport solution to be adapted to the technical/geometric difficulties/impediments.
Some transports used modern and ultralight semi-trailers from the Marraffa fleet which allow for leaner and less burdensome load configurations on the infrastructures with a weight/axle distribution below the limit thresholds.
The use of "spacer" elements was also fundamental, which made it possible to distance the group of front axles from the rear axles of the semi-trailer, a very important aspect when traveling on bridges and viaducts as the stress produced by the transit is divided into two phases .
Transport, handling and loading/unloading phases were carried out with modular trailers/semi-trailers. These are composed of modular steering axles, connected to each other by means of a hydraulic circuit which allows for uniform distribution of the load on the road surface and for reducing and/or increasing the height of the loading platform. This technology also allows the unloading (and subsequent reloading) of the items using beams and support elements (stools), thus avoiding the use of mobile cranes. The load is distributed fairly and uniformly also thanks to the width of the loading surface (3.00 m) characterized by the presence of 8 tires for each axle line.
Creativity in the transport solution
The geometric feasibility of the most demanding transports was made possible thanks to surveys that required a degree of accuracy down to the centimetre. During transport it was necessary to provide for the dismantling of urban furniture near critical intersections and sometimes it was necessary to provide for the increase in the height of the semi-trailers using the hydraulic circuit of the same to allow them to pass over obstacles (safety barriers, curbs , etc.). Where the dismantling was not enough, it was necessary to provide counter-flow maneuvers guaranteeing traffic safety with meticulous work of the technical stocks required by the highway code.
Construction site safety
Marraffa pays the utmost attention to the safety of its operators, of the transported load and of the people involved in the operations, guaranteeing a healthy and safe working environment. The entire project was carried out in total safety, in full compliance with the regulations currently in force (Legislative Decree 81/2008), including that on the correct anchoring of loads on our means of transport as per the UNI EN 12195-1 standard.
In particular, our Safety Office, following its qualification at the customer's premises, has drawn up a detailed Operational Safety Plan, concerning the activity to be carried out for the transport and positioning of the items on stools, prescribing the necessary PPE from use and the protective measures to be taken to avoid any accidents.