With its 80,000 sq.m. office area, the tower has become the most prestigious business center of Moscow International Business Center project. Besides offices, its twisted floors accommodate 36,000 sq.m. of shopping and entertainment center and covered parking area. This impressive building stands at a total of 245.9 meters to its tip. The highest occupied point is at an impressive 220 meters above ground level.
» The construction of Evolution Tower
Through the economic crisis and many subsequent design team iterations, the essential twisting form has endured. The appropriately named final product demonstrates the persistent value of a strong concept. The tower, against many odds, has definitively spiraled upward and taken its place in the city’s skyline, said Philip Nikandrov, the chief architect.
Construction began in 2008 but it was first proposed in 2005 and finally completed in 2015. The Tower’s construction combines state-of-art engineering techniques and features Russian Architectural styles. Each of the 54 floors is constantly twisted by 3°, whilst being arranged around the central core of the building, lets the skyscraper experience an elegant rotation in a clockwise direction from the base to the top by more than 150°.
» The uniqueness of the cold-bent glazing of the Evolution Tower
The proposed structural scheme with cantilevered continuous RC beams and cantilevered floor slabs picking up the overhangs from the twisted floor plates appeared to be simple, efficient and economical. The complex sculptural tower envelope was built using innovative cold-bent glazing with flat double glazed units cold-formed in 3D within the aluminum frame under its own weight, taking the shape of the frame without any thermal impact. Maximum deformation of one corner of the glass unit from the plane is no more than 50 mm. The end result is a façade that looks like a single shell of glass, curved in a spiral. Today, this curved facade is the largest cold-faced facade in the world. This approach appears to be both an energy-efficient and cost-efficient solution in comparison to the stepped curtain wall units previously applied in some twisted unitized facades.
The façade consists of 108 separate facade block-panels 4,3 m high and 1,5 m wide, 27 of which have different geometric dimensions of two different types, with an angle of inclination varying from +14 degrees to -14 degrees, which calls for the complex engineering of the project. The building's envelope features double glazed insulating units with heat strengthened, solar protection glass (8mm HS +6mm HS laminated +air gap +8mm FT coated solar protection glass). The multifunctional architectural glass significantly reduces the solar gain whilst providing the double glazed unit thermal performance equal to standard triple glazed unit normally used in Moscow to withstand harsh winter conditions.
» Cold-bent glass: an affordable solution for curved glass constructions
With cold curved glass technology, an affordable solution has been introduced for curved glass constructions retaining optical qualities. With cold bend glass, no heating takes place and does not have to be molded. This is a great advantage if break replacement is required. The product is constantly being developed. From cold-curable laminated glass to cold-curable insulating glass to integrate PV solar cells into the laminated glass. The last count in the sustainable family of cold curved glass is the cold curved triple insulation glass.
However, despite its growing presence in the international construction scene, this technology has been used sparingly. Concerns regarding long-term stresses and deformations induced on the glass and silicone by the cold-bending process may be one of the reasons for its sparse use. Nevertheless, the engineers and designers of successful cold-bent projects were able to use various methods of ﬁnite-element modeling and physical experimentations to determine the structural resiliency, code compliance, and warrantability of the curved glass. From these analyses and testing, glass manufacturers developed enough conﬁdence to warrant their glass products for use in cold-bending applications.