Engineering precision is a core value

The construction of a nuclear power station is by no means special solely because of the technology involved. The sheer number and specialised nature of the buildings also make it unique. The construction of the construction and assembly base required for the project is in itself a major domestic investment; moreover, facilities are being built that are unlike anything previously constructed in Hungary. The design documentation for all the structures passes through the Architecture Department of the Technical Directorate, whose work is overseen by Zsolt Tarkovács.

„I come from a family of engineers, and I’ve been interested in design and structural engineering ever since I was at secondary school. When I came second in the structural engineering final of the 1994 National Vocational Studies Competition, I knew that the path straight to the Budapest University of Technology and Economics lay ahead of me. My professional career began in 2000, when I graduated with a degree in civil engineering from the Faculty of Civil Engineering at the Budapest University of Technology and Economics, and then started working as a structural engineer,” he recalls of the start of his career.

He also obtained a degree in architectural engineering, but remained in the structural engineering field as a designer. He has worked on several major projects, notably the structural design for the planning permission, tender and construction phases of the KÖKI intermodal centre’s metro terminus and bus station. In early 2016, he joined the Paks II team as a lead structural engineering expert, and shortly afterwards was asked to head up what was then known as the Architectural and Site Survey Department.

„Contrary to what our name suggests, it is not only architects who work in the Architecture Department. Around twenty of my colleagues specialise in architecture, structural engineering, geotechnical engineering and hydraulic engineering, and are responsible for reviewing design documentation,” says Zsolt Tarkovács, describing their work. „The department is staffed by engineers with excellent professional expertise, most of whom have come from the private sector and possess 10, 15 or 20 years of design experience; they were drawn to Paks by the monumentality and complexity of the project,” adds the head of department.

The experts do not carry out design work in the traditional sense, but rather review and verify the plans and documentation prepared by the Russian main contractor to ensure they comply with Hungarian and EU legislation, standards, technical specifications and contractual requirements. The Architecture Department approves the technical design documentation for the structures to be erected at the nuclear power plant site and the associated infrastructure networks, from the building permit application through the construction drawings to the as-built documentation.

„Our staff are responsible for the design of every single facility at the power station. This represents a huge professional challenge and, at the same time, a tremendous responsibility.”

Special technical solutions are employed at many facilities. One such example is the central structure of the nuclear island, the reactor building, which houses the primary coolant circuit, its central component, the reactor vessel, the main circulation pumps, the steam generators and the volume compensator, as well as numerous safety systems, including the core melt trap. The reactor building is a double-walled reinforced concrete containment structure, which serves a safety function. Structurally, it is a post-tensioned reinforced concrete shell with a hermetic steel cladding on the inner side. The outer containment is designed to withstand tornadoes, extreme snow loads and even the impact of a passenger aircraft. Structures important for nuclear safety, including the reactor building, can withstand the effects of an earthquake with a return period of 100,000 years.

The turbine building is unique because the equipment housed within it – including the steam turbine and generator – is sensitive to vibration; for this reason, it is mounted on a so-called turbine table, which is isolated from the building by springs. Special technical considerations are required for the site’s deepest-founded structures: the water intake works planned on the banks of the cold-water channel, and the utility bridge spanning the cold-water channel, which will transport the water used for cooling into the hot-water channel. „There’s no shortage of technical challenges!” sums up Zsolt Tarkovács.

Building permits have already been obtained for all temporary structures, as well as for nearly thirty facilities within the site area, under project Paks II. Zrt.. „The expertise of my colleagues has contributed greatly to this, as has the review of site preparation activities – soil stabilisation, diaphragm wall construction, site demarcation, soil excavation and dewatering – played a key role in ensuring the design documentation was of the required quality so that construction could begin. We have also obtained the first water rights construction permit for the plant site. We are proud that, with the approval of the construction drawings for the foundation slab of the Unit 5 nuclear island, we have made a significant contribution to the achievement of the first concrete milestone. ”Among our current tasks, I would highlight the review of the technical design documentation for the building permit of the Unit 6 nuclear island structures,” he said.

He explained that the review of the planning and construction drawings is an ongoing process. He and his colleagues are continuing to work to ensure that the planning and construction drawings are available without interruption to keep pace with the construction schedule.

„Our aim is to ensure that the technical design documentation for power plant facilities is of sufficient quality and technical substance to support construction and safe operation, the benefits of which will be enjoyed by future generations.”

The head of department emphasises that they are in constant contact with the company’s other departments; technical discussions with the Russian designers take place on a daily basis, and consultations are conducted in English, the official language of the project.

No nuclear power stations have been built in Hungary in recent decades, so no domestic experience in nuclear construction has been accumulated; however, this fact in itself is not a problem, points out Zsolt Tarkovács. To deepen their nuclear expertise, they have taken part in visits to nuclear power plants similar to the one under construction at Paks – such as Leningrad II, Astravets, and Tianwan Units 7 and 8 – as well as attending specialist international conferences. The team also includes young colleagues at the start of their careers, who are supported and mentored by more experienced colleagues. Several members of the department have completed the specialist further training course in nuclear construction engineering launched by the Faculty of Civil Engineering at the University of Technology and Economics, including Zsolt Tarkovács.

„Engineering precision, accuracy, perseverance and a sense of responsibility are core values in my work,” says the expert, who has been working on the Paks II project for ten years with the same strong sense of motivation and is proud to be part of Hungary’s largest construction project.

As he points out, the pouring of the first concrete was an important milestone, as it marked the project’s transition into the „under construction” phase in international terminology; yet he is already looking forward to the time when dozens of tower cranes will be at work on the new nuclear power plant’s site and buildings—previously seen only on the drawing board—will spring up like mushrooms. “I am committed to building a power station of which we, our children and our grandchildren can all be proud!” – he articulates his mission statement.