Contemporary structures for neo-baroque headquarters

Recently, reported that the central bank's neo-baroque headquarters had been restored through a large-scale development project. As we were able to see for ourselves during a tour of the building, one of Ignác Alpár's most famous buildings has been reborn as a modern, energy-efficient office building, with the representative spaces having been precisely reconstructed.

The headquarters on Szabadság Square was designed by TIBA Építész Stúdió and was renovated by Raw Development Kft.. while the reinforced concrete structural work involved in the conversion and extension project was carried out by Épszerk-Pannónia Invest Kft.. In this article, we take a closer look at the tasks and difficulties involved in structural engineering, and learn about the unique challenges of adding modern technology to a historic building.

A complete reconstruction of the MNB building was carried out, during which the previous covering of the courtyard above ground level was removed and the courtyard of the building was given a 1320 m² glass dome, creating a large, bright interior atrium. Not only was the motif system of the building preserved during the renovation, but the balustrades with the monumental vine-floral ornamentation, the monumental chandeliers and the leaded glass panels were also reconstructed.

New structures, remaining values

As we learned from the staff at ÉPI, new structures also had to be built in the original building: pillars (freestanding and embedded in existing brick walls), walls, beams, frames, slabs, lift shafts, mechanical shafts and stairs were installed between the historic walls. The tasks of ÉPI were coordinated by two professionals who had previously received the Engineer of the Month award: while Bálint Szász, as director of the structural engineering division, was responsible for the structural superstructure of the additional floors (and en bloc) with his team, Péter Ilkei, chief engineer of the facility, and his team oversaw the structural conversion of the existing parts of the building. According to their information

Two storeys of roof construction were added to the former slab-on-grade, which meant that ÉPI had to build pillars, walls, beams, slabs, sloping slab-on-grade and stairs on the new parts of the building.

A number of additional structures, necessary upgrades and replacements were needed to bring the building up to the quality of its former quality in terms of spatial experience, while at the same time bringing its structure up to contemporary standards. An important part of this was the installation of steel opening replacement beams, which had to be fitted into the existing brickwork to accommodate the large number of new openings.

The nesting and mass splitting of brickwork required special attention from the structural engineers, within which the

• nesting (the new slab is fixed into the nests previously cut into the brick walls), the
• beam cutting (the positions of the beams for the new steel beams had to be cut out in the brickwork beforehand), and
• the most challenging task was the mass demolition of the brick walls (with the construction of preliminary supports and subsequent opening replacement structures).

Both parts of the building, including the listed and the new floors, underwent major reinforced concrete construction: the main works included the reinforcement of the pillars, the installation of the opening beams, the creation of the frames for the new openings, the installation of new slabs, 12 lift shafts, four mechanical shafts and four electrical shafts, as well as the installation of stairs.

"Another exciting challenge," they pointed out, "was the construction of the high pitched sloping slopes with variable roof heights, which gives the roof a spectacular architectural appearance."

Prefabrication is also beneficial in a listed environment

Several new reinforced concrete structures required special attention because of the listed heritage sites in their vicinity. To create the large new openings, the contractors used heavy-duty scaffolding (Doka SL-1) to build the preliminary spans, the design and negotiation of which, as they informed me, was an extremely complex and lengthy process.

During the complete replacement of the floor slab above the third floor of the new building section, new prefabricated ribbed prestressed shell panels and reinforced concrete floor structures were installed in place of the building's former top floor.