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History- Sources- Prestressed- Concrete

brief history of prestressed concrete
Academic year: 2022/2023
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Mariano Marcos State University

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HISTORICAL DEVELOPMENT OF PRESTRESSING

In 1872, Peter H. Jackson was granted the first patent in the United States for prestressed concrete design.

In 1886, he introduced the concept of tightening steel tie rods in artificial stone and concrete arches.

In 1888, C.F. Doehring obtained a patent for prestressing slabs with embedded tension steels in Germany.

J. Lund of Norway and G. R. Steiner of the United States tried early in the twentieth century to solve this problem, but to no avail.

C. Steiner (1908) recognized losses due to shrinkage and creep and suggested retightening the rods to recover lost prestress.

R. E. Dill used high strength unbonded steel rods. The rods were tensioned and anchored after hardening of the concrete.

PRINCIPLES OF CIRCULAR PRESTRESSING  Developed by W. Hewett in the early 1920s. He hoop-stressed horizontal reinforcement around walls of concrete tanks through the use of turnbuckles  The prestressing force is applied tangent to the axis of the member  LINEAR PRESTRESSING  Continued to develop in Europe and in France in 1926-1928, through the ingenuity of Eugene Freyssinet  The prestressing force is applied parallel to the axis of the member  Freyssinet System  Introduced by Eugene Freyssinet in 1940 which comprises the conical wedge anchor for 12-wire tendons.  Concept of prestressing extensively developed and used for the design and construction of numerous bridges in Europe.  Calculation rules for prestressed concrete - established by Yves Guyon of Paris.  Magnel-Blaton system - A prestressing anchorage system invented by Gustave Magnel of Belgium.  PARTIAL PRESTRESSING  was introduced and developed by Paul W. Abeles of England between the 1930s and 1960s. Various partially prestressed structures were built in England from 1949 onwards.  LOAD-BALANCING METHOD  was introduced by Tung-Yen in the early 1960s considerably simplified the design process of post-tensioning, particularly in continuous structures.  PRE-TENSIONED CONCRETE The first to use pre-tensioned (between 1935-1939) concrete where strands are tensioned before the concrete is placed and no anchorage devices are used.

THIN FLAT SLABS- Pre-tensioned with very small diameter wire between two buttresses at the ends

Ulrich Finsterwalder- He developed the double cantilever idea for prestressing or for prestressing construction.

The success in the development and construction of all these landmark structures has been due to:  the advances in the technology of materials, particularly prestressing steel, and  the accumulated knowledge in estimating the short- and long-term losses in the prestressing forces  SOURCES OF PRESTRESSING (Based on the location of the prestressing tendon with respect to the concrete section)

  1. EXTERNAL PRESTRESSING  The prestressing is achieved by elements located outside the concrete.  Unbonded tendons are placed, and prestressed, outside the structure anchored at the ends and sometimes with one or several deviators during the length of the structure.  This method is advantageous for strengthening of a structural member to obtain improved load carrying capacity. 
  2. INTERNAL PRESTRESSING  Prestressing is achieved by elements located inside the concrete member (commonly, by embedded tendons).  Most of the applications of prestressing are internal prestressing.  SOURCES OF PRESTRESSING FORCES (Based on the method by which the prestressing force is generated)

1. MECHANICAL PRESTRESSING

 In this type of prestressing, the devices includes weights with or without lever transmission, geared transmission in conjunction with pulley blocks, screw jacks with or without gear drives and wire-winding machines.  This type of prestressing is adopted for mass scale production.  2. HYDRAULIC PRESTRESSING  The simplest type of prestressing, producing large prestressing forces.  The hydraulic jack used for the tensioning of tendons, comprises of calibrated pressure gauges which directly indicate the magnitude of force developed during the tensioning

  1. ELECTRICAL PRESTRESSING  This type of prestressing is also known as thermo-electric prestressing.  The steel wires are electrically heated and anchored before placing concrete in the moulds. 
  2. CHEMICAL PRESTRESSING  Self-prestress  A process, in which expansion of concrete with special additives can be used to generate tension in the reinforcement and prestress in the concrete.  
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History- Sources- Prestressed- Concrete

Course: prestressed concrete (CE 159)

University: Mariano Marcos State University

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HISTORICAL DEVELOPMENT OF PRESTRESSING
In 1872, Peter H. Jackson was granted the first patent in the United States for
prestressed concrete design.
In 1886, he introduced the concept of tightening steel tie rods in artificial stone and
concrete arches.
In 1888, C.F.W. Doehring obtained a patent for prestressing slabs with embedded tension
steels in Germany.
J. Lund of Norway and G. R. Steiner of the United States tried early in the twentieth
century to solve this problem, but to no avail.
C.R. Steiner (1908) recognized losses due to shrinkage and creep and suggested
retightening the rods to recover lost prestress.
R. E. Dill used high strength unbonded steel rods. The rods were tensioned and anchored
after hardening of the concrete.
PRINCIPLES OF CIRCULAR PRESTRESSING
Developed by W.H. Hewett in the early 1920s. He hoop-stressed horizontal
reinforcement around walls of concrete tanks through the use of turnbuckles
The prestressing force is applied tangent to the axis of the member
LINEAR PRESTRESSING
Continued to develop in Europe and in France in 1926-1928, through the ingenuity of
Eugene Freyssinet
The prestressing force is applied parallel to the axis of the member
Freyssinet System
Introduced by Eugene Freyssinet in 1940 which comprises the conical wedge anchor
for 12-wire tendons.
Concept of prestressing extensively developed and used for the design and
construction of numerous bridges in Europe.
Calculation rules for prestressed concrete - established by Yves Guyon of Paris.
Magnel-Blaton system - A prestressing anchorage system invented by Gustave
Magnel of Belgium.
PARTIAL PRESTRESSING
was introduced and developed by Paul W. Abeles of England between the 1930s
and 1960s. Various partially prestressed structures were built in England from 1949
onwards.
LOAD-BALANCING METHOD
was introduced by Tung-Yen in the early 1960s considerably simplified the design
process of post-tensioning, particularly in continuous structures.
PRE-TENSIONED CONCRETE
The first to use pre-tensioned (between 1935-1939) concrete where strands are
tensioned before the concrete is placed and no anchorage devices are used.
THIN FLAT SLABS- Pre-tensioned with very small diameter wire between two buttresses
at the ends

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