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EUGÈNE FREYSSINET
HIS INCREDIBLE JOURNEY TO INVENT AND REVOLUTIONIZE
PRESTRESSED CONCRETE CONSTRUCTION
Pierre Xercavins, Daniel Demarthe and Ken Shushkewich
Presented by C.R. Alimchandani, STUP Consultants Ltd P. Ltd
36th Conference on OUR WORLD IN CONCRETE & STRUCTURES: 14 - 16 August 2011,
Singapore
Article Online Id: 1000360019
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36 Conference on Our World in Concrete & Structures
Singapore, August 14-16, 2011
EUGÈNE FREYSSINET
HIS INCREDIBLE JOURNEY TO INVENT AND REVOLUTIONIZE
PRESTRESSED CONCRETE CONSTRUCTION‡
Authors: Pierre Xercavins, Daniel Demarthe and Ken Shushkewich
Presented by *C.R. Alimchandani
STUP Consultants Ltd P. Ltd
1004 & 5, Raheja Chambers, 10th Floor, Nariman Point,
Mumbai - 400 021, India
E-mail: [email protected]
Keywords: prestressed concrete, bridges
Abstract. The vast achievements of Eugène Freyssinet and his prolific career span
five distinct phases:
World record span length arch bridges (1905-1928), Invention of Prestressed
Concrete (1929 – 1933), Rescue of the Le Havre Maritime Station (1934),
Proliferation of Freyssinet technology around the world (1934 – 1962), and Invention
of pre-cast segmental construction (1941).
It has been just over 100 years when EUGÈNE FREYSSINET STARTED HIS CAREER IN 1905 in
Moulins, France as Ingénieur des Ponts et Chaussées (Engineer of Bridges and Roads). He
approached problems in a graphic way using free hand drawings and simple calculations in the
margins and sometimes used Graphic Vector resolution where required.. He built numerous bridges
in the Moulins region. The Praireal-sur-Besbre Bridge built in 1907, a three hinged arch with a span
of 26 m was the first bridge in the world to have the arch lifted from the formwork by the use of
hydraulic jacks at the crown hinge. This was created by Freyssinet in a very early stage of his career.
Fig. 1: Eugène Freyssinet
One of the fortunate events in the life and career of Eugène Freyssinet was his close association with
likeminded contractors François Mercier, Claude Limousin and Edme Campenon.
__________________________________________
‡
Presented at fib-days 2010 at Delhi by *C.R. Alimchandani
Pierre Xercavins, Daniel Demarthe and Ken Shushkewich (Presented by C.R. Alimchandani)
Freyssinet patented Prestressed Concrete (pre-tensioning) in 1928, the Flat Jack in 1938 and the
concrete anchorage (post tensioning) in 1939. We will discuss this later in this lecture.
After the first stage of development of prestressing, Freyssinet had a small group of dedicated,
brilliant colleagues (they were all geniuses with an IQ of over 160). Yves Guyon, his Associate, gave
prestressing its mathematical basis, Pierre Xercavins, who joined in 1950 was involved in large
projects with Eugène Freyssinet, he soon followed Yves Guyon to become the Technical Director of
Europe Etudes which was the design subsidiary of Société Technique pour l’Utilisation de la
Précontrainte (STUP), which was created in 1944 to spread the knowledge of Freyssinet’s inventions
relating to Prestressed Concrete across the world they designed many bridges in France and
internationally. Pierre Xercavins was awarded the Fédération Internationale de la Précontrainte (FIP)
Medal in 1970 for outstanding work in Prestressed Concrete Structures and the Albert Caquot Prize in
1991 for being the best Civil Engineer in the world. He also designed many other large and complex
structures most notably the Montreal Olympic Stadiaii, Ekofisk and Ninian Offshore Platforms, the last
two being respectively the first and the tallest Prestressed Concrete Oil Platforms in the world. Pierre
Xercavins had the same approach to conception of structures as Eugène Freyssinet.
I was able to observe the works of Eugène Freyssinet and be a disciple of Xercavins for 2½ years.
Between 1958 and 1963 I shared the enthusiasm of Pierre Xercavins to spread the knowledge of
Prestressing with engineers all over the world. In 1963 I was sent to work by Yves Guyon for the
newly opened design office of STUP in India: STUP Consultants Pvt. Ltd. STUP Consultants Pvt.
Ltd. has now worked in 36 countries, has 1400 Engineers, Architects and Technicians and support
staff and still carries on Freyssinet’s, Guyon’s and Xercavin’s mission. I therefore, would like to offer
this tribute to these great men by presenting a summary of the Article made by Pierre Xercavins
about Eugène Freyssinet “EUGENE FREYSSINET HIS INCREDIBLE JOURNEY TO INVENT AND
REVOLUTIONIZE PRESTRESSED CONCRETE CONSTRUCTION” a short time before Mr.
Xercavins passed away in 2008. Whenever I was at the limit of my knowledge, from 1958 up to the
time he passed away, I was able to get advice from Pierre Xercavins. I also met along with Mr.
Xercavins, Mr. Yves Guyon, the First Technical Director of STUP France and Mr. Eugène Freyssinet,
whenever the solution of a problem required their advice. I have also to explain the role played by Mr.
K.K. Nambiar, the first Indian Chief Engineer of the erstwhile Madras State P.W.D. and Yves Guyon
in setting up STUP Consultants Pvt. Ltd. in India, without the technical courage of Mr. K.K. Nambiar
and his accepting Prestressed Concrete for the Palar Bridge, the use of this technique by India would
have been much delayed (incidentally, the Palar Bridge utilized the Magnel Blaton System of
Prestressing) – they encouraged the creation of STUP Consultants Pvt. Ltd. by becoming,
respectively the first Chairman and a Founder Director of this Company.
WORLD RECORD SPAN LENGTH BRIDGES
The long-term relationship between Freyssinet and the contractor Mercier started with the Veurdre
Bridge. During their period together Freyssinet designed and built concrete Arch Bridges, which
successively broke his own world records for span length. Due to financial constraints and
bureaucratic obstacles, money was not available for the Veurdre Bridge and two other bridges across
the Allier River: Boutiron Bridge, and Mercier’s friend Regnier was interested in the third bridge at
Chatel-de-Neuvre. They made a bold proposal undertaking to build all three bridges together for
630,000 Francs, which had been allocated for the Veurdre Bridge alone; Mercier assuming total
financial responsibility and Mr. Freyssinet the technical responsibility. The proposal never had to
pass an Inspection Committee as Freyssinet had to do the Design for Mr. Mercier and supervision of
the same for the Government – also Mercier agreed to be paid only after the work was completed.
Fig. 2: Veurdre Bridge (72.5 m span) (1911-1912)
The main problem during construction was the decentering of the long arches that were subjected to
creep and shrinkage. This was achieved by using thrusts created directly, following the procedure
first used on Praireal-sur Besbre Bridge. After constructing the Veurdre Bridge, Freyssinet kept on
observing the behaviour of the same. It was a very flat arch with a depth to span ratio of 1:15.
He observed deformations due to creep and shrinkage first slowly and then rapidly till collapse
seemed inevitable and he and his loyal workers replaced the Decentering Jacks in the early morning
when no one was around and raised all three vaults at once to the correct levels. The bridge
regained its shape and behaved perfectly until 1940, when it was destroyed during the IInd World
War.
This bridge on the Lot River consists of a plain concrete arch with a span of 96 m, a world record at
the time.
Fig. 3: Villeneuve-sur-Lot Bridge (96 m span) (1914-1920)
Construction was started in 1914 but was soon stopped due to the Ist world war. The bridge was
completed after the war in 1920.
The most interesting aspect of the bridges from the point of view of construction was the use of
Decentering Jacks – previously spans collapsed during decentering when the span was greater than
70 m. Freyssinet used them not only for striking the formwork, but also for correcting stresses after
construction created by deformation of the arch due to creep and shrinkage. Thus it was possible to
carry out this procedure at any time during the lifetime of the bridge.
Today, the bridge remains as natural in its urban setting as it did when it was first built. The bridge
has reddish exposed brick arcades that hide the spandrels resting on the arch and let the bridge
blend well with the buildings in town.
The Lot Bridge was followed by Saint-Pierre-du-Vauvray Bridge of 131 m span in 1922-23 which
again held the world record at the time.
Plougastel Bridge (3 spans of 186 m) (1925 – 1930)
The Plougastel Bridge on the Elorn River near the City of Brest, close to its harbour, consists of three
reinforced concrete arches each having a span of 186 m (610 ft), a world record at the time. The
reinforced concrete trussed double deck accommodates a roadway on the upper deck and a railway
on the lower deck (the railway over the bridge was never completed).
Fig.4 : Plougastel Bridge (3 spans @ 186 m)
For this construction, Eugène Freyssinet took advantage of the tides to bring on floating barges, an
enormous wooden truss, which was used for the successive construction of the three arches. The
truss was built on the riverbank, launched at high tide with the aid of two barges, and installed for the
construction of the first arch. After completion of a span, prestressing was used for raising up the
arch from the centering, the centering truss was then lowered and floated into position for
construction of the second arch, and then the third arch.
Prestressed Concrete Patent (1928) (Pre-tensioning).
Freyssinet first had the idea of compressing concrete by prestressing. It took twenty five years of
laboratory tests and profound thought to discover the difficulties involved and the ways to over come
them.
He applied for a patent for a “Fabricating Process for Reinforced Concrete Elements”. The process
was adapted to precast beams, pipes, sleepers, poles, etc.
At the time of the patent, in 1928, the Scientific Community did not believe in prestressing. Thus,
Freyssinet decided to go out alone to demonstrate the merits and possibilities of prestressing, risking
all his fortune, energy and reputation. He thus started producing electricity poles at the Forclum plant
at Montargis in France.
Fig.5 : Pre-tensioning (Forclum electricity poles)
He perfected the grinding fineness of cement to increase its strength, improved on his previous
invention of mechanical vibration, invented steam curing and perfected the industrial precasting
process. The result was a complete technical success but a total commercial failure due to the
depression of 1929.
In five years, he lost his entire fortune that he had accumulated during his past career. He never
regretted it because he had obtained technical results far more important than all of those which he
achieved between 1905 and 1928.
Flat Jack Patent (1938).
Eugène Freyssinet next invented the Flat Jack for compressing the raft of the Portes de Fer Dam in
Algeria and immediately after that on a much grander scale for raising the height of the Beni Badhel
Dam in Algeria by 7 m to bring it up to 67 m. the patent was applied for in 1938 and validated in
1939.
Fig.6 : Flat jack (schematic)
The Flat Jack is made of two stamped steel sheets connected by welding. By hydraulically
introducing a fluid under pressure, the flat jack is inflated and can develop considerable force. It is a
remarkable device for its power, lightness, and low cost. The fluid can be oil, resin, grout, cement, or
other ingredients. The Flat jack can be used to vary the compressive forces applied with time to allow
for adjustments of structures after their construction. The flat jack has been used on a great many
projects around the world, including the Montreal Velodrome described in this paper.
CONCRETE ANCHORAGE PATENT (1939) (Post Tensioning).
Eugène Freyssinet applied for a patent for “Tensioned Cable Anchorage System for Prestressed
Concrete Construction”. The patent was issued in 1947 (because of the war).
The system consists of 12 Nos. 5 mm diameter parallel steel wires locked or anchored in a concrete
anchorage cone by a tensioning jack. The steel wires which were threaded through the anchorage
consisting of a reinforced concrete cylinder having a central conical hole (female cone) and a central
fluted conical block (male cone). The steel wires were tensioned simultaneously with the aid of a jack
and locked-off by the male cone inside the female cone while under tension. The wires transmitted
their tension to the structure via the anchorage.
Fig.7 : Post-tensioning (concrete anchorage cone and tensioning jack)
This invention allowed tensioning to be achieved by resting on the concrete directly. The prestressing
cable could be long or short, rectilinear or curvilinear, and positioned inside or outside the structure
(external prestressing as well as internal prestressing). The force in the prestressing cable could be
adjusted during construction. This system gave the engineer a wide liberty in the position and
intensity of prestress that he/she wished to develop, and has been used in the construction of most of
the large structures since that date.
The original 5 mm wires were progressively replaced by 7 mm wires, then 8 mm wires and then by
seven wire strands. In the case of the concrete anchorage of 1939, the capacity was 20 T which was
replaced by a steel anchorage in 1960 with a capacity of 150 T. Individual wedges for each strand
came into existence in 1965 and a capacity of 200 mt was achieved.
SAVING THE LE HAVRE MARITIME STATION FROM COLLAPSE.
The Maritime Station in Le Havre completed in 1933 for the ocean liner Normandie, was sinking 25
mm (1 in) per month into a deep layer of clay, and according to Freyssinet “Imminent collapse
seemed to be inevitable. He wrote, I proposed a solution which, despite its boldness, was adopted
without argument as it constituted the only possible hope of avoiding disaster”.
Fig.8: Le Havre Maritime Station
The strengthening of this building in 1934 is considered to be the first use of devices for prestressing.
In the first stage, Freyssinet strengthened the foundations to make them monolithic by use of external
prestressing by Cables and Jacks at their extremities and then increased the bearing capacity of
foundations by adding piles that were driven in segments until they reached layers of soil which could
carry the loads without abnormal sinking.
Fig.9 : Le Havre Maritime Station elevation
Freyssinet solution consisted of adding new footings (B) between the existing footings (A) to make the
entire unit a monolithic prestressed horizontal element. The unit was prestressed with parallel wires
turned around two reinforced concrete end anchorages One anchorage was displaced by hydraulic
jacks having a force of up to 1000 mt (1100 tons). The link between the old and new concrete was
assured by the general compression of the whole. The moveable anchorage was fixed by concreting
the free space and the jacks were removed. The wires forming the cables were covered by concrete
to protect them from corrosion. The A units supported columns above while the B units had sockets
in them to drive piles through.
Fig.10 : Le Havre horizontal prestressing of footings
Fig.11 : Le Havre anchorage for horizontal prestressing of footings
Fig. 12 : Le Havre existing columns above and the sockets for new piles
below the combined footing
The second part of the Freyssinet solution was to install 700 piles, 25 to 30 m (82 to 98 ft) long that
extended to sound layers of soil. The piles were cast inside the building in 2 m (6.6 ft) sections, and
were assembled by prestressing and driven into the ground using special jacks designed by
Freyssinet. Vibration, compression, and steam curing of the concrete were all used to improve the
rate of casting and quality of concrete. The piles were then prestressed against the footing by means
of hydraulic jacks having a vertical prestressing force of 320 mt (352 tons). The settlement
immediately ceased as soon as the first piles were installed.
The result was both spectacular and convincing, and at once earned Freyssinet a worldwide
reputation. This created the opportunity for a meeting between Eugène Freyssinet and Edme
Campenon, and started the collaboration between the two in 1934 on the entire range of construction
projects of the Campenon Bernard group, a collaboration that finally was destined to ensure the
development of prestressing.
PROLIFERATION OF FREYSSINET TECHNOLOGY AROUND THE WORLD.
With success at Le Havre, the contractor Edme Campenon offered Eugène Freyssinet “the chance to
experiment, apply, and develop his invention of prestressing and his ideas on concrete construction,
on the entire range of sites of the Campenon Bernard group”. Later in 1943, Edme Campenon
created a special division called STUP (Societe Technique pour l’Utilisation de la Précontrainte)
[Technical Company for the Use of Prestressing] for the “development, protection, and
implementation of the techniques of which M. Freyssinet is the inventor”.
In 1961 STUP created a design company, Europe Etudes, so as not to restrict the development of
prestressing technique to the sole use of its original inventor and developer. STUP also wanted to
spread this technology all over the world. With this aim, in 1963, STUP started its design bureau in
Mumbai – STUP Consultants Pvt. Ltd. Today, STUP Consultants Pvt. Ltd. employs over 1400
Engineers, Architects, Technicians and supporting staff and has designed and implemented projects
in 36 countries. Today, STUP Consultants Pvt. Ltd. is active in all branches of Civil and Structural
Engineering, Architecture of Buildings as well as of Airports - including the associated Mechanical and
Electrical Engineering.
In 1976, STUP France changed its name to Freyssinet International. The group, at that time,
included a prestressing supplier, which was a disseminator of technical information around the world
(Freyssinet Company), a contractor (Campenon Bernard), and a designer (Europe Etudes).
In 1982 STUP Consultants Pvt. Ltd. separated from the Freyssinet Group as it wished to become an
independent consultant, but Mr. Alimchandani retained relations with Mr. Jacques Vattaire, Ex
Inspector General of Industry, who as President of ACTIM welcomed Mr. Alimchandani to France,
Mr. Lemoine Ex Chairman and Managing Director of STUP Consultants P. Ltd. France, Mr. S.
Kovanyko, Ex Chief engineer and Founder of STUP Consultants Pvt. Ltd., Mr. Pierre Xercavins, Ex
Technical Director of STUP France, Mr. Frank Guyon, who is the son of Mr. Yves Guyon, who was
the first Technical Director of STUP France. Mr. S. Kovanyko and Mr. Frank Guyon are still alive and
are Co-Gerants (Co-Managers) of Asie Etudes, France. The son of Mr Pierre Xercavins, Mr Laurent
Xercavins has his fathers Structural Engineering genius for Prestressed Concrete and is today the
person whom I consult when I have a problem beyond my knowledge.
INVENTION OF PRECAST SEGMENTAL CONSTRUCTION
The Luzancy Bridge over the Marne River (started in 1941 and completed in 1946 after the war), was
the first of a new generation of precast segmental bridges designed and constructed by Eugène
Freyssinet. It has a span of 55 m (180 ft), a world record at the time, and was built to replace an old
suspension bridge. It is very light in appearance and has a remarkable span to depth ratio of 1: 45.
Fig.13 : Luzancy Bridge (55 m span) (1941-1946) (first precast segmental bridge)
The Luzancy Bridge was visited sixty years after completion in October 2007 by me along with other
members of the Freyssinet Association. It is in pristine condition and the concrete of the precast
segments is of excellent quality.
Fig.14 : Luzancy Bridge in 2007
The bridge is an 8 m (26 ft) wide portal frame comprised of three box girders that were precast in
segments and assembled on site in sections. The bridge was prestressed longitudinally and
transversely with 12 – 5 mm diameter tendons, and vertically with 5 mm pre-tensioning wires that
were stressed prior to concreting. It was erected by launching equipment consisting of masts and
stay cables (one of the most imaginative systems ever used for the assembly of prefabricated bridge
elements).
The middle box girder being erected is 39 m long and weighs 90 T. All three of Freyssinet’s
inventions for prestressing (pre-tensioning, flat jacks, and post-tensioning were used here).
Fig.15 : Luzancy Bridge during construction
The Underground Basilica at Lourdes takes its inspiration from the Esbly Bridge of the Luzancy
lineage. The structure was conceived by Eugène Freyssinet in only fifteen minutes, designed by
Jean Chaudesaigues, and constructed by Campenon Barnard from 1956 to 1958. It consists of only
29 portal frames and can accommodate 20,000 people.
Fig.16 : Underground Basilica at Lourdes (capacity: 20,000 people)
Fig.17 :
th
Pierre Xercavins speaking at the 50 anniversary of the Basilica of St. Pius X at Lourdes on March
14, 2008 (photo courtesy : Association Eugène Freyssinet).
Choisy-le-Roi Bridge (1962-1964)
Jean Muller also a genius like Xercavins worked as a close collaborator and eminent disciple of
Eugène Freyssinet in Campenon Bernard and Company, pioneered match-cast technology in the
early sixties with the Choisy-le-Roi Bridge over the Seine River in France. On this bridge, he used for
the first time, precast segmental box girder technology with match-cast epoxy-coated joints. I visited
the site with Jean Muller, while outsiders were not allowed to visit unless the bridge was completed
and put into service. (In the precasting yard the previously cast segment was used as the end form for
the next segment, in order to obtain perfect contact between adjacent segments and to get directly
the final profile of the deck). This bridge has three continuous spans of 37.5m – 55m-37.5m (123ft180ft-123ft), with a total width of 28.4m (93 ft) that was divided into two parallel single cell box girder
bridges. A total of 148 precast segments were fabricated using the long-line casting method. Typical
segments weighed 20mt (22 tons). The bridge was erected in balanced cantilever using a floating
crane.
Fig. 18 : Choisy-le-Roi Bridge (1962-1964) (first precast segmental “match-cast” bridge)
Bear River Bridge (1971-1972)
The Bear River Bridge near Digby, Nova Scotia in Canada was the first precast segmental box girder
bridge built in North America using the match-cast method with epoxy-coated joints. This curved
bridge is 609 m (1998 ft) long with six interior spans of 80.8 m (265 ft) and two exterior spans of 62.1
m (204 ft). The bridge is 12.0 m (39.5 ft) wide. The 145 segments were cast in a plant located near
the bridge site using two short-line casting cells each producing one segment per day. The segments
weighed a maximum of 82 mt (90 tons), and were placed by a 180 mt (200 ton) mobile crane on land
or on a barge over water. The bridge was designed by A.D. Margison and constructed by Beaver
Marine Ltd., with construction engineering assistance provided to the Contractor by Europe Etudes
under the leadership of Pierre Xercavins and Daniel Demarthe.
Fig.19: Bear River Bridge (1971-1972)
(first precast segmental “match-cast” bridge in North America
Montreal Velodrome (1973-1976)
The Montreal Velodrome for the 1976 Olympic Games pays tribute to Eugène Freyssinet because it
incorporates so many of his prestressing and construction techniques. This very flat airy vault of
prestressed concrete and is supported at four abutments only, and is inscribed in a rectangle of 172
2
m by 130 m. The covered area without intermediate supports is 16, 000m .
Completed Structure
One of the most interesting phases of construction was the decentering (the transfer of loads from the
false work to the permanent supports at the abutments).
Structure during construction.
By placing flat jacks at the four abutments and jacking to an amount equal to the calculated reactions,
the roof slowly rose until the entire weight of the structure was taken by the four abutments only. A
total of 226 flat jacks each with a capacity of 1000 mt were used for the decentering. Once the loads
were transferred, the false work was removed giving a clear span of 172 m.
The veledrome was designed by Trudeau, Gascon, and Lalancette with technical assistance provided
by Europe Etudes under the leadership of Pierre Xercavins and Daniel Demarthe.
Flat jack scheme at Abutment
The main structural elements are six arches which spread away from the Z abutment, and meet again
in pairs on either side of the W, X and Y abutments. Two secondary arches connect the X abutment
to the W and Y abutments. The arches are comprised of 142 precast segments that are built using
the match-cast method with epoxy-coated joints, and erected on temporary false work. A network of
63 double Y-shaped beams span between the arches. The structure is completed with cast-in-place
concrete joining the arches to the abutments.
Structural Layout
Flat jack layout at Abutment
Decentered structure (172 m span)
Caracas Viaduct (1951-1953)
This bridge is notable for the method of using Prestressed Cables during the erection of centering for
this bridge.
Caracas Viaduct during construction
Bridge (1)completed
Bridges (2)and (3) completed
Caracas Viaduct Completed (1951-1953)
Orly Airport Bridge (1957 – 1959)
I visited this bridge under construction when I was a trainee– it was the first continuous bridge in the
world.
Orly Airport Bridge (1957 – 1959)
Saint Michel Bridge (1959 – 1962)
It has portals with slim piers in the direction of the water flow during floods. This was the first
prestressed concrete portal bridge carrying Railway lines.
Saint Michel Bridge (1959 – 1962)
CONCLUSIONS
Freyssinet repeatedly stated, “I was born a builder”. Indeed, he became totally immersed in the
building of his structures, “becoming simultaneously engineer, contractor, carpenter, form worker,
steel worker, cement specialist”. In the words of Jean Montagnon “If Eugène Freyssinet had been a
musician, he would have been a composer, an instrument maker, an instrumentalist, and a
conductor.”
Freyssinet also stated repeatedly that he had invented an entirely new material which led to “a
revolution in the art of building”. He continued to design and build until his death. Included in his
latter structures are the three arch bridges of the Caracas Viaduct from 1951 to 1953, the
Underground Basilica at Lourdes from 1956 to 1958, the Number 10 Bridge at Orly Airport from 1957
to 1959, and the Saint-Michel Bridge at Toulouse from 1959 to 1962. The Saint-Michel Bridge
opened in March 1962, three months before Freyssinet’s death.
th
Eugène Freyssinet has been proclaimed as one of the most complete engineers of the 20 century
and is certainly one of the greatest builders in world history.
I present this paper with some emotion as it includes slices of my life.

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