FAMA gaskets win Ministry seal of approval 15 July 2015

Italian tunnelling products supplier FAMA is recognised for its original contribution to underground sealing technology with the award of a new patent for its range of integrated anchored gaskets.

Profile view of the FAMA UG012A integrated gasket

The precast concrete segment sealing specialist – which designs, certifies and manufactures products for the precast concrete segmental lining of TBM-bored tunnels – is granted the patent by the Italian Ministry for Economic Development.

FAMA, founded in 1988, is the first Italian company to design and implement a gasket that is integrated into the formwork during the casting process, and which is permanently fixed to the concrete without the need for glue. The FAMA UG012A anchored gasket was successfully applied for the first time in Italy during construction of the subsea TBM-bored TERNA cable tunnel under the Messina Strait between Sicily and the mainland.

Other products from FAMA’s integrated gasket range have also been used during the construction of the Turin Metro and are due to be used during construction of the Riyadh Metro – the first TBM for which launched earlier this month.

Made of elastomer, the pre-cut gaskets – which are integrated into the formwork before the concrete segment is cast – are available in a range of sizes. Each gasket is produced to the specific dimension of the segments that require sealing.

The gasket is manufactured using an injection moulding corner joint process and covers the entire perimeter of the segment. The seal is established when contact is made between two gaskets of opposite profiles, enabling both longitudinal and annular sealing joints to be made. The gasket is designed according to the specific hydraulic pressure requirement of each project.

Gasket placed as part of segment casting process

Due to its particular geometry and internal structure, the FAMA integrated gasket ensures an effective hydraulic seal to be made at the lowest possible pressure applied on its surface – even in cases where there is a high level of offset and/or the distance between the segments is not optimised.

The corners are designed and manufactured with a geometry that replicates the geometry of the segment itself, to ensure a perfect dimensional and functional coupling of seals that are adjacent to each other.

Although FAMA also manufactures a range of more traditional glued gaskets, it claims there are significant technical and economic benefits to using the integrated solution. Installation time is reduced, and an improved quality of seal is offered by eliminating the potential for water penetration caused by the expulsion of the gasket from its groove. Incorporating the seal into the casting process eliminates the possibility of future problems arising in the demoulding phases, and ensures there is less opportunity for mortar infiltration into the joint.

FAMA President, Gustavo Bomden, said his company’s proactive R&D division was dedicated to innovation and to solving the challenges that tunnel contractors report back to them. “From the beginning, the company has dedicated itself to developing products that would have a global reach through their quality, sustainability and development. Our vision is to invest in R&D to solve the real problems in our field, add to our know-how, and create original products.”

He added: “Relationships with excellent Italian research institutions have allowed our company to develop its niche, and to differentiate ourselves from our competition.” To this end, FAMA sponsors a specialised Master’s Degree course in tunnelling and TBMs offered by the Politecnico of Turin.