Izmir Adnan Menderes Airport New Domestic Terminal constructed by TAV Construction, the 2nd largest company in airport construction, started operations as of 17 March 2014. Constructed with an in-vestment of 266 million Euros and completed in 21 months by TAV
Construction, the new domestic terminal has a closed space of 200.000 sqm. Project being the largest domestic terminal also includes a closed carpark with a capacity of 2.537 cars and an open carpark with a capacity of 3.000 cars. Architectural design is by Yakup Hazan Architecture whereas structural design is by Statica Engineering.
Terminal is constructed over a total area of 291.267 sqm. With the completion of the construction, 200.000 sqm space is added to the usable area of 110.000 sqm in the existing International Terminal. 220.000 cubic meter of concrete and 15.000 tonnes of construction steel is used in the construction of the terminal. Designed with 64 check-in counters, 40 elevators, 30 escalators, 666 meters of moving walkways and a luggage capacity of 5.000 luggages/hour as per its capacity of 25 million passangers per year, the terminal will be operated by TAV Ege, subsidiary of TAV Airports, until the end of year 2032.
TAV Airports realized each and every design, construction and operation process of the new terminals within the framework of enviromental sustainability policies. With “Waste Management Policy” put into practice during the demolition of the old terminal building, 99% of the waste material is reused or recycled. The policy is awarded with “Innovative Sustainability Practices Award” presented for the first time by Sustainable Development Association (SKD). Application for Leadership in Energy and Environmental Design (LEED) certification Izmir Adnan Menderes Airport New Domestic Terminal and Carpark was made in December 2012. New Domestic Terminal will be the first airport terminal building to be certificated by LEED in Turkey.
A spacious design is foreseen for passen-gers departing from New Domestic Terminal to easily observe the planes in apron and take-off. To form the spacious areas created by the unique architecture of the terminal, various roofs and courtyards to be located on the reinforced concrete main structure are designed with structural steel. Since the airport is located on first-degree seismic zone, several creative details which are appropriate for the architectural design and structurally safe were designed and solution were developed accordingly.
The focus point of the terminal design is the diagrid vaulted roof with dimensions of 200 m x 80 m in the plan covering the check-in hall in departure level entrance with a clearance of 72 m, and four diagrid hyperboloid cone “elephant feet” structures developed with architectural steel. Interior spaces of the four elephant feet with bottom diameters of 15 m and 20 m in two types are designed as commercial spaces. Elephant feet are detailed to support the majority of lateral and vertical seismic loads of the vaulted roof.
Terminal main structure and deck struc-ture where departure lounges are located are connected with a gallery of 400 m and this gallery also acts as a structural joint separating the two structures physically. Roof structure of the gallery having a clearance of 27 m is designed with architectural steel originating from an origami form consisting of architecturally folded plates. Entirity of one side of the origami roof is designed as a roller sup-port to adapt with displacements at a level of +/- 30 cm in both directions on horizontal plane due to different movements of the two separate structures under seismic loads. Along the gallery covered by the origami roof, there exists a road structure designed and elevated from the floor level with structural steel (called “flying road”) to allow transport of transfer passangers between domestic and international terminals with electric cars.
In addition to the vaulted and “origami” roof, “sail” roofs architecturally originating from its form and the concave roof enabling transition between domestic and international terminals are constructed with space frame system due to convenience in installation and possibility of flexible geometry formation. Since the deck structure on the apron side of the terminal forms the continuation of the deck in international terminal, this structure is again designed with “sail” columns originating from the form with structural steel.
Glass canopies at the terminal entrance are produced from composite material with photovoltaic cells to form shadow and produce green energy to the terminal from solar energy. Connection detail element at the tip of the pin support steel pipe elements forming the supporting system of the canopy is formed with cast structural steel.
Vaulted Roof
To reduce the necessity of welding on site and increase the construction speed, the vaulted roof is designed with modular prefabricated hallow members with custom bolted connections. A total of 1.752 no. built-up 40 cm x 60 cm sections were manufactured with longitudinal welding of two S355N class steel U-plates. 14mm or 16mm plates were used for welding for manufacturing of the hallow sections. 2.400 tonnes of structural steel is manufactured in total for the roof.
All members (except the cross-section plane angle) at the connections are manu-factured with a drill angle of approximate-ly 4 degrees to ensure that members are architecturally located in accordance with the roof plane. Connecting plates at the tips of elements are welded in custom double formworks to form the angle at the connections.
With the embedded cross element at 48 the common joint of four members, it is detailed by using 32 no. 10.9 HR standard prestressed bolts are used. Top side of connection tips of the elements are left open for placing the bolts and top of the support is connected with welding continuity plates joining four elements together. A total of 829 connections are installed. In design, vertical seismic load in addition to the horizontal seismic load is considered due to large clearance of the roof. It is observed that member connections are subject to similar critical loads at both major bending axis due to diaphram loads created by vertical loads with horizontal loads on the roof plane.
One fairlead fixed support detail on one side and a pin-connection support detail is connected on the other side of main supporting beams at two edges of the roof. Main reinforced concerete beams on two sides are connected to each other with 7 tension rods for roof integrity and to control displacements. Tension rods are furnished with load sensors to continuously monitor the roof behaviour and recorded information is accessed by the relevant people over the internet.
Elephant Feet
Supporting reinforced concrete beams along the two sides of the vaulted roof are supported by reinforced concrete circular composite columns with a diameter of 120 cm and built-up I-sections inside. These columns allow economy for the roof with the use of elephant feet columns as supporting elements where they were initially designed for architectural purposes since the roof does not have sufficient rigidity alone on the short edge and provide significant contribution to the roof structurally in the sense of horizontal rigidity.
Elephant feet are typically designed with pipe elements of CHS 273 x 16. The indicative fact for the choice of pipe cross-sections was that the roof is to provide the structural rigidity which will limit horizontal displacements under seismic loads. Continuity in load transfer is typically provided by cross plates at pipe connections and welds between the pipes, and geometric reference is thus set during installation. Full penetration welding is used at nodes located at half length of the elephant feet from the bottom. Site welding is kept at minimum by pre-production of the elephant feet with several separate parts between each node level before installation, factory installation of 3-layer parts and sending the bottom parts to site.
Elephant feet structure and interior glass façade elements are connected only from top and bottom edges like curtains with horizontal circles composed of independent steel pipes. Glass façade is detailed in a manner to protect the glass elements from movements to occur due to earthquakes with joints between glass façade elements and independent supporting circles.
To ensure conformity between the structure and the elements in movements during an earthquake, system and connection details were developed in the design of all façades in the terminal in general, including the courtyards. Thus, bulky elements in the façades are avoided and risk of glass elements breaking during an earthquake, which poses a threat for the passangers, is minimized.
Structurally compatible with the seismic zone and functional Izmir Adnan Menderes Airport New Domestic Terminal, designed by Turkish architect and engineers and a unique and aesthetic structure, is presented to our country as an exemplary application to structural steel.