The structures of the piers, whether they are in reinforced concrete or steel, are subjected to severe environmental conditions which cause severe corrosion and deterioration.
Blue Shark boasts high specialization in the rehabilitation and reinforcement of the structures in the wharf at the Sarroch Refinery, operating under a framework contract performing the various ordinary and extraordinary maintenance.
Reinforced concrete structures are usually restored with cycles that include the demolition of deteriorated concrete parts that no longer guarantee the design resistance, the passivation of the metal reinforcements and the subsequent reconstruction of the sections with the use of special high-performance fibre-reinforced mortars.
Steel structures are normally restored by removing the existing paints and oxidized surface parts by sandblasting, with the possible replacement of metal parts unable to offer the design resistance and with the subsequent coating with specific painting cycles .
The structural reinforcements of concrete structures, generally made up of poles, pulvinos, portals and decks, can be subject to reinforcement due to load increases or adaptation to regulations; various techniques can be used, including the increase of resistant sections, reinforcement by application of carbon fiber composite materials, coupling of steel reinforcement structures.
Reinforced concrete briccole and pulvinos very often show advanced phenomena of deterioration of the concrete and metal reinforcements. The recovery takes place in various stages.
The first activity to be performed is the demolition of deteriorated and/or carbonated concrete.
Prior to the restoration, carbonation tests are carried out to establish the front and determine the demolition depth.
The reinforcing bars are treated through passivation cycles.
The reinforced concrete sections are reconstructed using specific fibre-reinforced mortars.
When necessary, the structures are reinforced by applying carbon fiber composite materials.
The structures of the slabs are restored by removing the deteriorated and/or carbonated concrete; the reinforcing bars are passivated using specific products; the intrados is rebuilt by applying specific thixotropic mortars.
If necessary, the intrados of the slabs is reinforced by applying carbon fiber composite materials.
Reinforcing pier piles often require jacketing the piles with steel shells.
All steel structures are prefabricated in the Blue Shark Group workshops located in the industrial area of Macchiareddu.
The metal shells, suitably treated on the surface with specific painting cycles, were coupled by clamping; the cavity between the inside of the metal shell and the pole was finally filled by injection of specific controlled-shrinkage mortar.
In particular situations there is a need to carry out reinforcement interventions on the metal poles by coupling metal shells welded to the same poles; for the execution of the welds below sea level, specific metal structures called “bells” are used; the latter are fixed to the pole by means of clamping. The operator carries out the welding activities from inside the bells guaranteeing the necessary quality.
In this specific case, Blue Shark has made in its workshops, in addition to the reinforcement interventions, also the bells necessary for the execution of the work. The positioning of the bells and reinforcement by welding are performed by specialized personnel with specific training.
All the metal parts that make up the reinforcements and the necessary complementary works are prefabricated at the Blue Shark Group workshops located in the industrial area of Macchiareddu.