Who Was Branko Žeželj

Branko Žeželj (Benkovac, 14 March 1910 – Belgrade, 20 February 1995) was a Serbian civil engineer, structural designer, inventor, university professor and academician. He is best known as the creator of the Yugoslav system of concrete prestressing and as the designer of structures that defined postwar construction: Belgrade Fair Hall 1, the road-rail bridge over the Danube near Novi Sad, and the Beška Bridge.

As director of the Federal Construction Institute and a long-serving researcher at the Institute for Testing of Materials (IMS) in Belgrade, he gathered a team of young engineers around him. Together they developed technologies that brought Yugoslav construction into the international mainstream. The technology known as IMS Žeželj remains a byword for prefabricated construction in prestressed concrete.

Origins and Youth

Branko Žeželj was born on 14 March 1910 in Benkovac, in northern Dalmatia, then part of Austria-Hungary. Most sources, including the Serbian Academy of Sciences and Arts and Wikidata, give Benkovac as his birthplace. The international structures database Structurae lists Zadar, so sources differ on this point.

Little is publicly known about his family and childhood. He attended primary school in his hometown. He then moved to Split, where he completed secondary school.

Education

After finishing secondary school in Split, Žeželj went to Belgrade. He enrolled in the civil engineering department of the Technical Faculty of the University of Belgrade and graduated in 1932 with the title of graduate civil engineer.

He later became part of the academic community himself. He taught structural engineering subjects at the Faculty of Civil Engineering in Belgrade, where, according to SASA, he became a full professor in 1964.

Work Before the War and the Second World War

Until the outbreak of the Second World War, he worked as a design engineer in the Bridge Section of the Ministry of Construction. At the same time, he worked as a teacher at the Secondary Technical School in Belgrade.

According to the newspaper Novosti, he spent most of the war in German captivity. He managed to escape from the camp, and that source places this in 1944. After his escape he joined the National Liberation Struggle. For that reason, Serbian Wikipedia also lists him as a participant in the National Liberation Struggle.

Postwar Career and the IMS Institute

After the war, Žeželj became head of the Bridge Section of the Federal Ministry of Construction. He then took over as director of the Federal Construction Institute. At the Institute for Testing of Materials he was a principal research fellow from 1954 to 1979, and for a time its director.

He knew that experienced engineers would be slow to accept new technology. According to Novosti, he therefore gathered young colleagues who, as he put it, had not yet been shaped by established practice. His close associates included engineer Boško Petrović, who began his professional career working alongside Žeželj, and Branislav Vojinović.

The IMS Institute building on Bulevar vojvode Mišića, not far from the Fair, was the first prestressed concrete structure in Yugoslavia. It was built as an experiment. For prestressing, instead of new steel wire, workers used wire from the unraveled cables of a prewar suspension bridge on Brankova Street. The building was first erected on Bosanska Street and then moved to its present site.

Prestressed Concrete and Inventions

The center of Žeželj’s interest was prestressed concrete. He worked on applying it to large structures, bridges and halls, without the use of scaffolding. His anchor and prestressing jack found wide use in Yugoslav practice.

According to the Faculty of Civil Engineering in Belgrade, he created the Yugoslav prestressing system. He was the author of a large number of inventions at home and abroad. They include serial construction of industrial halls, prefabricated bridges, concreting bridges without scaffolding, the first prestressed concrete bridges and prefabricated residential buildings. There were also a pressure reactor vessel, railway sleepers and power transmission pylons.

The number of patents varies between sources. Novosti reports 24 patents, while Serbian Wikipedia speaks of about thirty original solutions and more than sixty designed structures. It is therefore safer to say that he held between roughly twenty and thirty patented solutions.

He also worked on fundamental research into concrete pressure vessels for reactors. His bold and technically new methods were adopted in many countries around the world.

He spoke about his material almost poetically. Concrete, he said, has its moods, and an engineer’s task is to master it and make it behave as intended.

Belgrade Fair Hall 1

One of his best-known works is Hall 1 of the Belgrade Fair. In the 1953 competition for the Belgrade Fair, first prize went to architect Milorad Pantović and engineers Branko Žeželj and Milan Krstić. The hall was built between 1954 and 1957.

The dome of Hall 1 is ribbed. It rests on a ring that is prestressed three times over. The ring takes up the enormous horizontal thrust of the dome, which is resisted by a prestressing system carrying about 1,500 tonnes of force. Žeželj decided that a 1:10 scale model of the dome should be built at the IMS Institute, with every detail and the reinforcement reproduced to scale. The tests confirmed a high degree of safety.

At the time of construction, the dome set a world record for span. Most sources give a span of about 109 meters, although some cite 108 or 107 meters. Hall 1 remains one of the largest universal halls in the world and has the status of a cultural monument.

The Žeželj Bridge in Novi Sad

The best-known bridge he designed was the road-rail bridge over the Danube between Novi Sad and Petrovaradin. It was built between 1957 and 1961. Officially it was called the Brotherhood and Unity Bridge, but residents always called it the Žeželj Bridge, after its designer.

The bridge had two arches with spans of 211 and 165.5 meters. The roadway was suspended from the arches. It used radial cable prestressing of the arch cross-section, a method patented by Žeželj. For this solution he received an award at the World Congress for Prestressing (FIP) in Rome in 1960.

Because the technology was new, many doubted the safety of the bridge. According to Novosti, during the load test Žeželj sat in a boat beneath the bridge while the heaviest freight train crossed over it. The bridge passed the test and served for almost four decades.

In the NATO bombing of April 1999, the bridge was hit several times and destroyed. Sources differ on the exact date of its destruction, giving both 23 and 26 April. After a long wait, the new bridge opened to rail traffic at the end of March 2018. It opened to road traffic on 1 September 2018. Residents still call it the Žeželj Bridge.

The Beška Bridge and Other Bridges

Žeželj also designed the Danube bridge near Beška on the Belgrade – Novi Sad – Subotica motorway. It was built between 1971 and 1975 by the company Mostogradnja. Its longest span is 210 meters, and the total length of the bridge is about 2.2 kilometers. A second, identical bridge for the opposite direction opened in 2011.

The Beška Bridge was badly damaged in the NATO bombing of 1999. It was nevertheless temporarily repaired and reopened to traffic on 19 July 1999.

His other works include the road bridge over the Tisa near Titel, as well as bridges built using the same prestressed concrete technique. In 1968 he also published a study on the feasibility of a 320-meter concrete arch bridge near Dubrovnik, made of prefabricated elements assembled in cantilever. He spoke about that idea in his inaugural address at SASA in 1970.

The IMS Žeželj System

The IMS Žeželj system was developed at the IMS Institute in Belgrade and first applied in 1957. It is based on a prefabricated skeletal structure of columns and floor slabs joined together by prestressing with steel cables. The idea was simple: build standard buildings from standard elements.

The system was open and flexible, allowing different apartment layouts and facades. According to Novosti, a third of New Belgrade was built using this system. During the 1970s the technology spread beyond Yugoslavia, and prefabricated buildings were erected with it in Cuba and Angola.

Scientific, Professional and Public Work

He was elected a corresponding member of the Serbian Academy of Sciences on 21 December 1961 and a full member of SASA on 7 March 1968. He was also a corresponding member of the Academy of Sciences and Arts of Bosnia and Herzegovina. At SASA he chaired the Board for Civil Engineering and the Interdepartmental Board for the Industrialization of Residential Construction.

He held numerous professional and public posts. He was president of the Union of Yugoslav Laboratories for Research of Materials and Structures, the Yugoslav Society for Soil Mechanics and Foundation Engineering, and the Yugoslav Society for Prestressing. He also chaired the “Nikola Tesla” society and the Committee for Science and Economy, and he was a member of the Scientific Council of Yugoslavia.

As a guest lecturer he appeared at international congresses and universities, including in Moscow, Leningrad, Kyiv, Athens, Prague, Budapest, Sofia, Rome and Havana.

Greatest Achievements

• Belgrade Fair Hall 1 – a prestressed concrete dome, a world record for span at the time of construction.
• The Žeželj Bridge in Novi Sad – a road-rail bridge from 1961, awarded at the FIP congress in Rome.
• The Beška Bridge – the longest Danube bridge in Serbia, built in 1975.
• The IMS Žeželj system – a prefabricated skeleton technology applied in Yugoslavia and abroad.
• The Yugoslav prestressing system – the foundation of domestic use of prestressed concrete.

Personal Life

There is no reliable publicly available information about Žeželj’s family or spouse, so none is given here. It is known that he rowed, and he enjoyed hunting and underwater fishing. Friends remembered that he liked good wine but almost never drank strong spirits.

His student and colleague Branislav Vojinović wrote that, despite all his knowledge and titles, Žeželj respected everyone’s opinion, from engineers to workers, and only then made a decision.

Final Years and Death

Branko Žeželj died in Belgrade on 20 February 1995, three weeks before his 85th birthday. SASA records 19 February as the date of death, but most sources, including Serbian Wikipedia and Wikidata, give 20 February.

His burial place is not publicly known.

Interesting Facts

• While a test freight train crossed the bridge near Novi Sad, Žeželj, according to Novosti, sat in a boat beneath it.
• The first prestressed concrete building in Yugoslavia, the IMS Institute building, was erected using wire from the unraveled cables of a prewar suspension bridge.
• The dome of Hall 1 was tested on a 1:10 scale model at the IMS Institute.
• A film about him, titled “Branko Žeželj”, was made by Dunav Film in 1995.
• He chaired the parliamentary group for scientific research and inventions of the Economic Council of the Federal Assembly of Yugoslavia.

Awards and Recognition

• Award at the World Congress for Prestressing (FIP) in Rome, 1960.
• October Prize of the City of Belgrade, 1956.
• 7th July Award, 1957.
• AVNOJ Award, 1966.
• Order of Labour of the second degree, 1949.
• Order of Labour of the first degree, 1956.
• Order of Merit to the People with golden star, 1963.
• Order of the Republic with golden wreath, 1968.

Legacy and Influence

Experts agree that Žeželj brought Yugoslav construction into the wider world. The term “IMS Žeželj” is still used across the planet. His prefabrication system is the subject of research and exhibitions, and in 2025 an exhibition titled “Prefabricating Solidarity: IMS-Žeželj Between Yugoslavia, Cuba, and Angola” was held about it.

Since 2015, the Civil Engineering Technical School in Belgrade has carried his name, as he himself taught at that school. In 2019, the street naming commission in Novi Sad decided that a street in Salajka would be named after him. The new bridge in Novi Sad is still popularly called the Žeželj Bridge.