Connectivity Set Free

Dome-shaped design flies in Alicante Airport terminal

Alicante Airport is the sixth largest airport in Spain and is the gateway to the Costa Blanca resort region. Alicante airport ranks sixth in the Spanish airport network due to affluent passengers, behind Madrid, Barcelona, Palma de Mallorca, Malaga and Gran Canaria, ranking among the 50 busiest airports in Europe. Growing in size continuously over the past years, in March 2011 Alicante airport got a brand new terminal building, replacing the old two terminals. The main intention to add new terminal buildings was for the future Alicante's airport at its maximum development. The final configuration

Flexibility and Modularity

A repetitive dome structure is designed as the characteristic element of the airport terminal, to meet the needs for future extensions and flexibility in the functional layout. The modular design can be easily expanded without modifying the overall image of the project. "The main reason for using the dome-shaped roof was to give flexibility and modularity to the building so that it can easily adapt to future modifications and expansions. The design for the terminal responds to master plan based on future traffic prognosis for the airport and surrounding area," says Mr. Fairbanks. The final configuration of the master plan contemplates a second runway parallel to the existing with terminal and satellite buildings in between giving service to both. The terminal building is defined as a 'U' shape building, with passenger processing areas in the centre and boarding piers at either extreme parallel to the runways. Landside access ways and parking structures are allocated on the inside of the 'U'.

 The layout designed for the final stage of the development is a 'U' shaped terminal and satellite building spanning between two parallel runways, the existing one and a future runway planned to the north. The current design, which fulfils less than 50 percent of that vision, is made up of an 'L' shaped terminal extending towards the future runway. "For the design concept, it was important to find a solution that could meet the traffic demands for the year 2020 and at the same time be capable of expanding to meet future demands, maintaining a unified integrity throughout all phases," he adds.

 Other issues prevalent in all airports such as passenger flows, baggage handling and commercial requirements are continually changing making it necessary to design for flexibility, finding solutions able to adapt to these changes. The design of a roof from a series of domes gives the Alicante terminal modularity and flexibility, with a singular identity in all of its planned phases. Future additions can be made by adding more domes, without tarnishing the image of the building. The dome structure allows for large spans with few supports giving flexibility in the distribution of its functions. Each dome has a large glass surface in order to guarantee an abundance of natural light in the interior of the terminal.

Aesthetic and spatial elements

Aesthetic and spatial elements dominate in airport design. Airports being complex buildings, without exaggerating that fact, some are large enough to be considered small cities given the number of people that work in them, the people that pass through them, the shops and restaurants. More than half of the surface areas of an airport are never even seen by the passenger; baggage handling areas, offices, mechanical rooms, loading and storage areas. Mr. Fairbanks suggests that when designing an airport, it is important to have a clear understanding of how all of these areas work, their different circulation patterns and functional needs. Once this understanding is achieved, the design process is about finding the best building form to meet the requirements, reducing walking distances and creating clear circulation patterns without interferences. The aesthetic and spatial aspects of the project are an important part of this process that must be developed working hand in hand with the functionality.

The decision to use a series of domes for the roof of the terminal was taken for many reasons, one of which was because of its structural possibilities; capable of making large spans with lightness of material. Once this decision was made, the effort of translating the design into a structure was more about looking for the correct form and construction methods to be able to produce the structure by industrial means," he adds.

Dome structure

The decision to use a steel structure for the domes was because of its ability to adapt to an industrialized fabrication process. A total of 40 domes complete the roof covering over 55,000 square meters of surface area. The roof system is made of insulated wood sandwich panels which span three meters between secondary structural elements. Sandwich panels are made with treated particle board on the exterior and laminated wood on the interior finished in natural birch to provide a quality finish. He further adds, "The structure was detailed with repetitive elements in order to permit a

Curtain wall

Border domes are detailed in order to adapt to the curtain wall. The curtain wall structure is composed of a series of vertical vierendeel every 4.5m hung from the arch shape trusses on the facade edge of the dome. The curtain wall is also integrated into the buildings systems, designed to maximize the use of natural lighting while reducing heat gain by direct solar radiation. It takes on a different character according to orientation in order to maximize the use of natural light in the building. South and East facades are treated with a double glass walls due to their solar exposure and for acoustical control given they are both airside facades. Exhaust air is used to create a controlled flow of cooled air in the airspace cooling the interior wall and reducing solar radiation gains. North and West facades have a single curtain wall design given that they receive almost no direct sunlight, the North facade because of orientation and the West facade because it is protected by a large porch spanning over the curb-side roadway.

Feel light- design approach

Other issues prevalent in all airports such as passenger and flows, baggage handling and commercial requirements are continually changing making it necessary to design for flexibility, finding solutions able to adapt to these changes. The design of a roof from a series of domes gives the Alicante terminal modularity and flexibility, with a singular identity in all of its' planned phases. Future additions can be made by adding more domes, without tarnishing the image of the building. The dome structure allows for large spans with few supports giving flexibility in the distribution of its functions. Each dome has a large glass surface in order to guarantee an abundance of natural light in the interior of the terminal.

It is important to mention that the terminal of Alicante was designed using a holistic approach with an emphasis on the integration of energy efficient systems. The air conditioning system is by means of displacement, where air is treated at the basement level and released with low velocity at floor level making it necessary to cool only the first two meters occupied by passengers and not the complete volume of the building. The elements of diffusion follow the modulation of the dome, each dome having its respective components.

The airport terminal is a place for transition between land and air; therefore it should have a feeling of lightness. The first airport terminals were modeled after train stations in order to give a feeling of security to departing passengers by creating a familiar atmosphere where they feel comfortable. Most of these were classical designs made with heavy materials of stone and concrete. "As the airport terminal evolved, finding forms that better adapt to air transportation requirements, the aesthetics of the terminal building also evolved as architects look at the aircraft industry for form and lightness. In the case of our terminal at Alicante we have tried to achieve this by providing an abundance of natural light and by making the structure as light as possible."