##press.download.headline##
##press.media.headline##
Already during the project development phase, PERI worked closely with the investor and general contractor, Ghelamco Poland, and shell contractor, Monting, in order to create a formwork solution to efficiently and, above all, safely realize the planned architecture. Thanks to PERI´s great wealth of experience with hydraulic climbing formwork, a well thought-out and technically sound plan was developed that took into account both the challenges of the complex building form as well as making it possible to comply with the tight construction schedule. In addition, the PERI planning concept made a convincing case due to the very high level of integrated safety features for the execution and optimum availability of even large quantities of materials.
A climbing solution customized for a special structural shape
The key challenge for the climbing protection panel of the office tower is the required adaptation to the variable elliptically-shaped storey slabs. Furthermore, a weekly cycle per floor is necessary to maintain the short construction period. The RCS rail climbing system provides the flexibility needed to meet these requirements. For anchoring to the floor slabs, horizontally cantilevered RCS climbing rails have been used which make accommodating the varying length of cantilevers possible and thus easily compensate for the projections and recesses in place between the floor slabs. At the same time, anchoring ensures that the protection panel is always securely connected to the building. As the floor slabs of the Warsaw Spire have to be pre‑tensioned, the climbing protection panel has been designed with three platforms. This offers access on all sides of the building to the designated working areas on the front sides of the slabs.
For the formwork for the core walls, PERI engineers combined the ACS self‑climbing variants with platform as well as gallows: whereas the platform system provides generous storage and working areas for the core walls which are formed in advance, the formwork for the semi‑circular outer walls of the core is suspended on the variant with gallows. With the VARIO GT 24 girder wall formwork, the construction team has achieved a high degree of dimensional accuracy as well as particularly good wall surfaces.
An RCS landing platform is also being used: in combination with rentable system components taken from the VARIOKIT engineering construction kit, the platform forms an ideal erection area for a 4‑ and 6-storey stair tower. The PERI UP stair construction provides continuous access to the top floors – regardless of how the assembly of the precast stairs in the building core is progressing.
The climbing formwork as well as the climbing protection panel move from floor to floor without the need of a crane: the ACS self‑climbing formwork functions using a climbing device with 100 kN lifting power while the RCS climbing protection panel is lifted upwards by means of mobile climbing devices.
Proven standard solutions for columns and slabs
For the circular columns of all three buildings, the construction team achieved best concrete surfaces with the steel SRS circular column formwork; for all rectangular columns, TRIO column elements are being used.
The large‑sized slab areas feature a wide range of elliptically‑shaped ground plans and are formed with the proven SKYDECK panel slab formwork. The aluminium system features particularly lightweight and practical system components. Furthermore, the simple and systematic assembly procedure accelerates the formworking activities. As SKYDECK is equipped with drop heads, striking the slabs can take place earlier. This means panels and main beams are available at an early stage for the following sections. The advantage for the site management is that on‑site material requirements are significantly reduced.
For the two flanking office towers, the SKYDECK system is supplemented at the slab edges with slab tables which are quickly lifted to the next storey each time in one crane lift together with attached PROKIT edge protection and the mounted supports.
Formwork, scaffolding and engineering from one source
PERI has been supporting the formwork and scaffolding activities for the Warsaw Spire in numerous ways. In addition to supplying the materials, there is a range of services that have helped the construction team to efficiently realize this architecturally challenging building complex. At the beginning, the detailed planning of the formwork solution was based on meeting the exact requirements of the investor whilst taking into account the practical handling aspect for the contractors, Monting. During construction of the building´s shell, the PERI rental park in Płochocin supplied the required quantities of materials thus ensuring the timely implementation of the tight schedule. Last but not least, the work on the facade is being carried out using PERI UP scaffolding. The modular scaffold system provides a high level of efficiency thanks to the decking with integrated lock against lifting and faster assembly.
The close and constructive cooperation between PERI and Monting for meeting the entire formwork and scaffolding requirements has minimized the interfaces and ensured high transparency and efficiency in the execution.
The Warsaw Spire
Three structures form the new building complex in the Polish capital: a 220 m high tower is flanked by two semicircular buildings, each 55 m high. Designed by the Belgian architects Jaspers Eyers & Partners, the tower is very distinctive due to its special shape: the floors feature an elliptical ground plan which varies from floor to floor. The shell is 188 m high and, with the addition of the eponymous "Spire", the building reaches its planned overall height.
After completion, a glass facade encloses the structure; the waisted design half‑way up the building gives the office tower its distinctive, very slim‑looking silhouette. Continuing upwards, the facade cantilevers out a considerable distance from the main building. The tower is 12 m higher than the previous tallest office building in Warsaw, the directly adjacent Warsaw Trade Tower. The Warsaw Spire is also the tallest office building in the country. According to the investor, all buildings meet the strict requirements in place regarding ecological and energy‑optimized operations.