Design ConceptThe design for the Mixed Use Center Baku proposes a high density building complex as landmark in view from the city and the sea. The hybrid composition of building elements is shaped by various factors: urban and climate considerations, economies of structure and materials as well as the proposed heterogeneous program are all combined in this complex design as a refined expression of their synthesis.Location/ SiteThe site of the Mixed Use Center Baku is located in the new city center, the Nizami District. The old town center and the Fountain Square in the west, the Central Railway Station in the north, and the Parliament in the south all together create a very lively urban environment. The close Baku Bay shore park Boulevard and many public parks and plazas around the area facilitate public outdoor spaces and recreation sources in this new vibrant urban development.The surrounding city fabric consists mostly of lower buildings with mixed uses, now interspersed with new commercial and luxury residential high-rise developments which start to determine the modern face of the Nizami District. These, and new financial headquarters, medium size department stores and hotels around the site make the location a perfect starting point for a highly dense urban Mixed Use Complex.Program/ OrganizationThe high end Residential Tower sits on the south-west side on top a podium building containing the Shopping Center, while the Five Star Hotel & Office Tower marks the building block's corner in the south-east on Pushkin Street. The horizontal strips in the Shopping Center's façade are shaped according to main people flows, entrances, traffic circulation and surrounding public zones.A special feature of the project is a spiral VIP ramp situated near the main entrance of the Shopping Center that leads to a spectacular drop-off area on the upper level, 20 m above ground at the main lobbies of the Residential Tower and the Five Star Hotel. Another highlight is offered as part of the Wellness and Spa Area within the Shopping Center: a combined pool and aquarium feature that hovers like a huge glass drop at the core of the shopping event space. On the roof level it serves as an outdoor swimming pool with a fully transparent glass basin for VIP guests and residents, while doubling as a skylight to the shopping Center Atrium, the Shopping Plaza and Foyer level below. From there, the visitors have a spectacular view on a large shark aquarium suspended from the Atrium ceiling which surrounds the pool, in turn encircled by a spiral ramp which connects the different levels of the Shopping Center. Thus the visitors moving upwards enjoy the view to the sky on sharks and bathers through aquarium and pool while being illuminated by atmospheric water reflections of the natural and artificial light.The Themes of the Proposal" Landmark and Identification" Towers as Urban Signs" Visibility and Transparency" Recognition Value" Density and Variety" Synergy of Forms and Functions" Vertical and Horizontal Massing" Hybrid Mixed Use Program" Variety of Typological Forms" Urban Liveliness" Complexity of Organization" Living, Shopping, Working, Recreation, Entertainment" Communication, Interchange and Exchange" Office, Hotel, Lifestyle, Wellness" Layering of the Shopping Base and Foyers" Public and Private spaces" Outdoor and indoor Plazas" Rooftop Recreation" Roofscapes" Intersection of Urban and Natural Landscape (Urban Hanging Gardens)" Sustainability" Environmental and Energy Design" Sun, Wind, Green" Structural Design for PermanenceStructural DescriptionThe building project comprises two high-rise structures - referred to below as 'Residential Tower' and 'Hotel Tower' - with a height of 150 m each. Both of them are integrated in a base or podium building.Residential TowerThe Residential Tower has 32 storeys with a typical footprint area of approximately 1,000 m² including a core of 10 x 10 m. The principal actions that determine the tower's load carrying structure are horizontal loads resulting from wind and earthquake excitation. The floors in the regular storeys are reinforced concrete slabs with a thickness of 32 cm. A flat roof slab guarantees a maximum of flexibility concerning building services and MEP and the prospective usage of the building.The unsymmetrical floor plans and the fact that each storey is rotated with respect to the one below and the one above gives rise to torsional moments along the tower height due to wind and earthquake actions. These torsional moments necessitate inclined columns at the perimeter of the structure that add to the torsional stiffness and load carrying capacity of the core.Vertical floor loads are taken care of by the core and columns. These are situated on a rectangular grid of 8 by 8 m around the core and thus provide a load-bearing structure that is straight from top to bottom. Additionally, parapet walls provide further stiffness because due to the rotated floors the floor slabs protrude by a 6 m maximum beyond the outer row of columns, so that vertical deflections can be kept within acceptable limits.The core of the high-rise building is a conventional reinforced concrete sheer wall structure. For all structural members of the building a fire resistance of 120 minutes is achieved.The foundations as well as the basement walls are planned as an impervious tray to protect the basement from dampness coming from ground water. The foundation is designed according to recommendations from the soil expertise as a pile-raft-foundation, where the piles and the raft foundation are acting as one member whose settlements are reduced.Hotel TowerThis high-rise structure faces the first one and has 26 storeys. The footprint area is 33 x 33 m with all storeys above level 5 of uniform shape. The floors below are part of the podium structure. Lateral stiffness is provided by a core with an area of 16 x 16 m and the façade, which consists of inclined, beam-like elements of varying height and shape that are rigidly connected with the floor slabs. In this way horizontal and torsional forces can be accommodated. In order to avoid imposed deformation due to temperature changes, the load bearing elements of the façade are covered with adequate thermal insulation.Vertical forces are carried by columns that are situated in the plane of the façade and belong to the horizontal grid of 8 x 8 m that is also applied throughout the base structure. The floors are designed as flat reinforced concrete slabs with a thickness of 32 cm and thus identical to those of the residential tower. The core consists of conventional reinforced concrete shear walls. Fire resistance requirements are met in the same way as for the residential tower.Since the vertical loads that have to be transferred into the foundations are of the same order of magnitude as that of the Residential Tower, the same concept is applied.Base StructureThe base structure stretches between both towers and provides, among others, room for a shopping center and a rooftop garden that is accessible via a ramp. There are between four and seven floors above and four floors below ground level.The vertical load bearing elements consist of columns which are situated on a rectangular grid of (again) 8 x 8 m. Regarding horizontal forces, like from earthquake action, the shear walls as well as the cores of the two towers provide sufficient resistance. The foundation concept is the same as that previously outlined for the two towers.The ramp that connects ground level and rooftop garden has the shape of a spiral with a diameter of 28 m. The sides of the ramp are braced with parapet walls that span between vertical columns. In such a way vertical deformation under live load can be kept within acceptable limits.Environmental, Energy and Building Services ConceptStrategies employing the building's shape in order to optimize energy performance together with the use of renewable energy sources (solar, wind, geothermal and biomass energy) to condition the spaces ensure an energy efficient design and reduce reliance on fossil fuel energy sources. The buildings are designed for high energy performance, high indoor thermal comfort and indoor air quality. The use of multiple layers in the case of the residential tower building skin construction allows the creation of buffer zones and shaded outdoor spaces. These in turn provide noise and solar protection for the living spaces.In the façades of all buildings however, effective, externally located and automatically controlled solar control devices are used to minimize the external cooling loads. These are configured to allow adequate daylighting when in use. Highly efficient mechanical ventilation systems with minimized pressure drop and a high energy recovery are provided to supply the spaces with fresh air. A "mixed-mode-concept" is emplemented, whereby natural ventilation of apartments, hotel rooms and office spaces is possible during a large portion of the year. Special elements in the façade provide pressure equalization at high wind speeds. Cooling and heating are provided by low noise fan coil units.Floor plans are zoned and coordinated with the façade design to provide maximum use of daylight and high energy performance. Daylight and views are given high priority. Rainwater is collected and used for landscaping. Planting and appropriate material selection reduce the "heat island" effect. A substantial proportion of the buildings energy demand is met by on-site renewable energy sources: solar collectors provide hot water for swimming pool use and domestic hot water supply, and drive also the absorption chillers in summer. Building integrated wind turbines provide electrical power. These are specially designed to provide maximum efficiency in the typically turbulent urban wind conditions and are supplemented by building integrated photovoltaic modules. Rejected heat from the chiller plant is used to produce warm water for use in the building complex (swimming pools and domestic hot water services). A biomass cogeneration plant fulfills the dual purpose of providing ecological benefits and ensuring security of supply, rendering any additional standby power generation plant unnecessary.Geothermal energy is harnessed for building heating and cooling. Ground heat exchangers are incorporated into the building foundations. The use of local building materials reduces the so-called embodied energy of the building complex. Mechanical plant rooms are located in the basement area and at roof level. An integrated security system is implemented including CCTV (close circuit television) surveillance of public areas, full function access control at selected entrances and lifts and central monitoring equipment within a main lobby security and reception desk. A complete Building Management System (BMS) is provided consisting of multiple Direct Digital Control (DDC) data processing outstations and a central management system.