The completion of Plot 21a, the latest phase of the monumental Belgrade Waterfront development, in December 2021 marks the latest step in a profound transformation of the Sava River waterfront area of Belgrade, Serbia. Penetron Admix, a crystalline concrete waterproofing solution, was specified over a conventional membrane system to counter the high water table from the Sava River, only 100 m from the construction site.
Belgrade is the capital city and largest commercial center of Serbia. It lies at the confluence of the Danube and Sava Rivers and is home to 1.2 million inhabitants. The city is a key industrial center for Serbia and Southern Europe. Many international railroad lines pass though Belgrade. Highways and river vessels traveling up the Danube from the Black Sea or arriving from Western Europe via the Main-Danube Canal also serve the area.
The US$3 billion Belgrade Waterfront development is between Belgrade’s historic old town (“Stari Grad”) and the new district of Novi Beograd. This is an enormous urban complex rising on the right bank of the Sava River. Once completed, the 1.8 million m2 of gross construction area will comprise 250,000 m2 of office space. It will also be home to 7,000 apartment units, and eight hotels.
Creating a New City District
“The Belgrade Waterfront project will also be integrated into the adjacent Sava Park. This is an extensive green space with sports and recreational facilities, including a multifunctional playing court, outdoor table tennis tables, a 700 m jogging track, a picnic area, a children’s playground, and a communal garden,” adds Theodor Mentzikofakis. Mentzikofakis is the Managing Director of Penetron Hellas.
The newly completed Plot 21a phase comprises the “BW Arcadia” and the “BW Aurora” residential towers. These feature an in-house kindergarten, verdant atrium gardens, and a ground floor retail area of shops. It also features a supermarket, and restaurants. Located directly opposite Sava Park, the two 23-floor buildings house 488 apartment units. They are available as 1- to 4-bedroom layouts and penthouses.
The construction site location facing the Sava River made the groundwater situation a concern for the general contractor. Initially, the considered a traditional waterproofing membrane system. However, with numerous below-grade concrete structures of the Plot 21a project exposed to the hydrostatic pressure due to the groundwater, they needed a more reliable and practical solution. During the planning phase of the project, the Penetron Hellas team presented a comprehensive concrete waterproofing solution to Mašinoprojekt KOPRING, a high-rise engineering company, and Strabag, the general contractor.
“By offering an integral waterproofing solution that requires no conventional or secondary waterproofing systems, we were able to show how Penetron Admix was a more durable, maintenance-free solution. It would substantially extend the lifetime of the Plot 21a concrete structures, but also help keep this phase of the project on schedule, thanks to its ease of application,” explains Theodor Mentzikofakis. “As a result, Strabag recommended the use of Penetron Admix.”
Resisting High Hydrostatic Pressure
Beton Plus was the ready-mix concrete supplier. They mixed Penetron Admix into 25,000 m3 (32,700 yds3) of concrete. They used this for the structures of two basement floors to counter the high hydrostatic pressure from groundwater levels exacerbated by the nearby Sava River. Approximately 8,000 m (5 miles) of PENEBAR waterstop strips were used to seal the construction joints.
Easily mixed in during batching, the active compounds in Penetron Admix penetrate deeply into the concrete structure. It fills the micro-cracks, pores, and capillaries with an insoluble crystalline formation. This prevents water and water-borne chemicals from entering the concrete structures. It does this even under the high hydrostatic pressure generated by the Sava River. In addition, any cracks that may develop during the lifetime of the concrete automatically self-heal. This results in waterproof and durable concrete for the lifespan of the structure. It requires no further maintenance or treatment.
“Work on the next stage of the Belgrade Waterfront development is already in full swing,” adds Theodor Mentzikofakis. “The Penetron System is being added to the new building foundations as we speak.”
About The Pentron Group
The Penetron Group is a leading manufacturer of specialty construction products for concrete waterproofing, concrete repairs and floor preparation systems. The Group operates through a global network. It offers support to both the design and construction community through its regional offices, representatives and distribution channels.