Extension of the existing facilities for maintenance and repair of aircraft for Lufthansa Technik Sofia

Technical indicators: 

• Total Build-up area: 20 054  sq.m. 
• Build-up area: 9450 sq.m.

Subproject: New Service Building with site networks, partial reconstruction of Hangar 2; 2-extension and 1A

The building includes - a basement, five floors above ground and a flat roof on which HVAC facilities are located. It houses an office, workshops, utility rooms, canteen with kitchen and catering. It is a service building for the complex and includes the main administrative and sanitary facilities. 
The construction of the main building is mixed, consisting of precast concrete elements and monolithic washers, walls and staircases. It is divided into two dynamically independent bodies by means of an anti-earthquake joint, which also crosses the foundations. The floor structure consists of pre-fabricated floor beams and panels, with 2T section panels at elevation 0.00, where the repair rooms are located, due to the higher service loads. From the second floor up to the roof on all levels are made hollow - floor panels type "Spirol".  The floor beams on all levels, as well as the roof beams, are of L and 2L cross-section, which are prefabricated in the factory. The columns are also prefabricated elements which are only involved in the bearing of the vertical loads. For the absorption of horizontal seismic forces, monolithic washers are provided from the base of the building to the level of the roof structure. In the basement volume, an underground reinforced concrete tank with monolithic walls and a roof monolithic slab at elevation ±0.00 is envisaged.
On the ground floor level, a warm connection to Hangar 1 has been established via a covered transport corridor along the northern façade of the building. From there, aircraft parts are brought in for repair in workshops located on the ground level of the main building.

Subproject: New Hangar 1 for maintenance and repair of aircraft and site networks
The building constitutes a New Aircraft Repair Hangar 1 and the necessary ancillary facilities, having the necessary parameters to accommodate one wide-body Airbus A380 or three narrow-body Airbus A321 aircraft simultaneously, so that it is possible to inspect, maintain, repair and fully service the above aircraft. The hangar building is a single-storey, single-span building without basement, of single-span truss steel construction with a column spacing of 91,70 m. Within the hangar volume there are monolithic internal buildings containing service, technical rooms and offices for the administrative staff. 
The light area of the main hangar volume is 5 676 sq.m.
In the repair area two main overhead cranes, each with a lifting capacity of 12,5 tonnes, and two auxiliary cantilever cranes, each with a lifting capacity of 1 t, are provided.  
A segmental lifting hangar door with dimensions of 89,73 /19,41 m and electrically operated, with the possibility of full and partial opening and insertion of one or three aircraft individually, is installed along the entire length of the northern façade. The segments of the door have an aluminium lifting structure and shafts for stepping and fixing in the hangar flooring.