Repairing the plinths of the Pejo 3000 cable car, located at 3,000 m elevation in Italy’s Stelvio National Park, demanded quick work, easy application and permanent protection. PENETRON, a surface-applied, integral crystalline waterproofing material, ensured the project’s success this past November 2019.
The Stelvio National Park is located in the far northeastern corner of Italy, next to Switzerland and Austria in the midst of the Central Alps., It is the country’s largest national park, it featuring breath-taking vistas of glaciers, waterfalls, glacial lakes and rivers, dense forests, Alpine farmlands, and picturesque villages. In the heart of the Stelvio National Park is the Pejo 3000 cable car, comprised of two 100-seat cabins, which, in minutes, takes skiers and hikers from Tarlenta (2,000 m/6,600 feet) on the valley floor, all the way up to the old "Mantova" refuge (3,000 m/9,900 feet) in the heart of the Ortles-Cevedale mountain range in the Italian Alps.
“Because of the extreme environmental conditions commonly found at an altitude close to 3,000 m, the square concrete bases – or plinths – of the cable car support towers showed clear signs of serious concrete deterioration,” explains Enricomaria Brac, Managing Director of Penetron Italy. “The plinths were severely corroded. Even the underlying reinforcement bars were exposed, which could compromise the structural integrity of the upper towers.”
The Pejo 3000 cable car was inaugurated in 2011 and, until recently, the deterioration of the plinths reached a depth of over 10 cm (4 inches) below the original concrete surface. As a result, the concrete plinths were constantly exposed to snow and sub-zero weather conditions, typical for Alpine winters, leading to concrete deterioration from successive freeze-thaw cycles.
“During colder seasons, ice and snow melts during the day, thanks to warming daytime solar radiation. This water progressively penetrates the concrete matrix and fills the voids and cracks within the concrete. In the evening, temperatures decrease, and this entrapped water freezes. Water expands when frozen, producing internal pressures, causing the concrete to crack and spall.” and adds Enricomaria Brac. “Exposed concrete at this elevation requires an enhanced degree of durability to survive the extremes of the Alpine environment.”
The extreme simplicity of applying PENETRON made it possible to carry out the repairs close to the "Mantova" refuge end station despite the challenging Alpine weather conditions and accessibility constraints to the actual repair site, which was limited to the cable cars.
The Penetron System is the ideal solution for waterproofing and protecting existing structures when the operating conditions demand comprehensive resistance to freeze-thaw cycles. Applied to the concrete surface by brush or spray, PENETRON penetrates deeply into the concrete matrix in the presence of moisture. The ensuing chemical reaction fills microcracks, pores and capillaries in the concrete with an insoluble crystalline formation, which prevents water and water-borne chemicals from entering, even under high hydrostatic pressure.
“The trick is to remove moisture from the concrete matrix – and keep it out,” says Enricomaria Brac. “This will substantially increase the life span and durability of concrete. Finally, any cracks that develop during the lifetime of the concrete are self-healed by PENETRON. That’s true permanent concrete protection.”