Two business towers incorporating glass and white vertical sections in contrast to the blue horizon of Bay of Kaštel have completely altered the visual appearance of city area at the base of Marjan. The monumental but elegant towers, at the western entrance to Split, under the modern façade hide a number of underground levels. Reliability and functionality of the underground sections, which are also the carriers of the tall skeleton, are party due to the DRACO waterproofing systems.
How we overcame the challenge
The large, successful and physically tedious job was met by experienced waterproofers at DRACO materials. Work on the -15 meter underground and +50 meter aboveground structure demanded the full dedication of workers, and also the design engineer when planning the waterproofing systems. Experience dictated the selection of material which could be relied on to meet all the challenges, meaning that DRACO BENT 500 was used in the underground section, and DRACO PLAN150 on the roof and under the thoroughfare surfaces. DRACO BENT 500 is a bentonite membrane containing sodium bentonite granules which retains waterproofing properties under conditions for a hydrostatic pressure of up to 70 meters. The DRACO BENT membrane is placed in the building pit after pumping out the underground water, and it is important to emphasize that the remaining moisture surface does not affect the waterproofing properties of the membrane. Due to the great depths of the construction pit, the cost-effective conclusion was to not expand it beyond the dimensions of the building and lean the peripheral walls of the underground section onto the walls of the construction pit. The DRACO BENT 500 membrane adapted well to this method and was incorporated on the shotcrete walls of the construction pit over which dense rebars were placed and the wall was constructed. Concreting the slabs and walls after placing the waterproofing membrane enabled the fibres in the bentonite membrane to encapsulate with the concrete thereby preventing the seeping of water underneath, and its penetration as well. All penetrations through the slab and walls were protected using the DRACO BENT 110 bentonite paste and the DRACO BENT 100 granules, and all concreting sections were covered with the DRACO WATERSTOP 500 sealing strip. For sections where a bentonite membrane was carried out on concrete walls, the completed membrane at terrain level overlaps with the DRACO LASTIC 100 polymer cement coating. Another challenge, but only for those not suffering from acrophobia, took placed 50 meters above ground. The DRACO PLAN 150 single ply TPO membrane was installed on the roof, and which is characterized by very high UV and mechanical resistance. Due to the entire installation complex which is located on the roof, every penetration was treated in detail, and all membrane endings were additionally sealed using the DRACO FLEX sealant.