The main objective of seismic protection is to ensure maximum protection of the population, to guarantee the continued operation of all emergency services and to maintain the continuity of operation of major infrastructures.

  • Applications
    Buildings
    Hospitals
    Schools
    Bridges
    Industrial facilities
    Heritage structures

Our experts are regularly called upon to address seismic strengthening issues. They respond to the needs by proposing tailor-made solutions combining special seismic devices and/or advanced structural strengthening techniques.

We offer infrastructure operators technical solutions for seismic strengthening projects, both for standard buildings (single-family homes, apartment buildings, schools, hospitals, offices, etc.) and for large structures such as dams, bridges and industrial plants.

Seismic retrofitting

A complete range of services

Structural assessment

An optimal retrofit solution can only be found after an accurate diagnosis of the resilience of the structure. We propose a comprehensive approach, adapted to the type of structure, with a recommended on-site investigation programme and preliminary modelling of the as-built structures.

 

Specification and conceptual design

Depending on the level of seismic protection chosen, we develop a technical specification and design strengthening strategies according to the architectural requirements and execution constraints of the project. Our solutions include the most advanced concrete and steel repair technologies and seismic protection devices through our ISOSISM® range.

Sizing of seismic devices

When the solution for upgrading the structure calls for seismic devices from the ISOSISM® range, Freyssinet carries out a pre-dimensioning of the devices using an advanced numerical model of the structure to be reinforced, in order to facilitate the final dimensioning by a design office.

Execution of the works

We repair and reinforce the steel or concrete structure to be upgraded, and then supply and install the earthquake protection devices.

Seismic retrofitting

Why choose Freyssinet for your project?

01. High value engineering

Our specialized engineers will advise and evaluate the best protection options for your project and will design and size the selected solution thanks to advanced digital modelling.

02. In-house design and manufacturing

The ISOSISM® range is entirely designed and manufactured in our design offices and factory in Milan (damping, isolation, connection, junction systems).

03. In-house testing facilities

With over 1,400 seismic devices tested since 2017, our ISOLAB® laboratory is the most active in Europe in this field. Our devices are tested according to the main relevant international standards (EN 15129, AASHTO, AS 5100, NCh2745, etc.).

04. A solid track record

More than 200 references for buildings (Turkey, Italy, Romania, Chile, etc.) and 700 references for engineering structures (Greece, Italy, Mexico, United Arab Emirates, Philippines, Algeria, Panama, Romania, Turkey, Bulgaria, Georgia, Taiwan, Canada, etc.).

The main seismic retrofit strategies

The seismic repair or strengthening strategy must be adapted to each type of structure, depending on its level of stiffness.

To reduce the vulnerability of low ductility structures, it is often more effective to make them stronger so that they can resist higher seismic forces, rather than trying to improve their ductility.

The aim is to give the structure greater deformability before failure, without increasing the forces to which it is subjected, so as to distribute the seismic action throughout the structure and make better use of its resistance capacity.

Seismic isolation involves inserting isolators between the substructure and the superstructure to significantly reduce the energy resulting from the seismic action transferred to the superstructure.

1. Increasing the strength of the structure

Earthquake resistance can be improved by increasing the strength of the structure. Structural elements can be strengthened or the whole structure can be made stronger by using the advantages of additional prestressing, dry shotcrete, steel bracing and carbon fibre reinforced polymer composites.

Additional prestressing

This strengthening technique is well suited to the seismic strengthening of structures and can serve multiple purposes: (1) Strengthening of concrete structural elements by introducing compressive stresses (2) Stabilising a structure by pre-stressing it on its foundations to prevent it from lifting in an earthquake (3) Making adjacent structures monolithic to improve their overall resilience.
  • Strengthening concrete structures
  • Connecting the superstructure to the substructure
  • Making adjacent buildings monolithic

Dry shotcrete

Dry shotcrete reinforcement can be used to improve the strength or resilience of structural elements by increasing their reinforced concrete section.
  • Strengthening of beams
  • Shear wall reinforcement
  • Columns jacketing

Steel bracings

Bracing complements the existing bracing of the structure, usually a building, to better distribute the lateral actions experienced by the structure during an earthquake and increase its resilience. By combining seismic dampers with bracing, it is possible to dissipate a significant amount of energy even over very short strokes.
  • Improving the lateral bracing system
  • Strengthening the structure
  • Increasing energy dissipation

Additional prestressing

This strengthening technique is well suited to the seismic strengthening of structures and can serve multiple purposes: (1) Strengthening of concrete structural elements by introducing compressive stresses (2) Stabilising a structure by pre-stressing it on its foundations to prevent it from lifting in an earthquake (3) Making adjacent structures monolithic to improve their overall resilience.
  • Strengthening concrete structures
  • Connecting the superstructure to the substructure
  • Making adjacent buildings monolithic

Dry shotcrete

Dry shotcrete reinforcement can be used to improve the strength or resilience of structural elements by increasing their reinforced concrete section.
  • Strengthening of beams
  • Shear wall reinforcement
  • Columns jacketing

Steel bracings

Bracing complements the existing bracing of the structure, usually a building, to better distribute the lateral actions experienced by the structure during an earthquake and increase its resilience. By combining seismic dampers with bracing, it is possible to dissipate a significant amount of energy even over very short strokes.
  • Improving the lateral bracing system
  • Strengthening the structure
  • Increasing energy dissipation
2. Increasing the ductility of the structure

Increasing ductility means making the structure more deformable before failure, without increasing the forces to which it is subjected, so as to distribute the seismic action over the whole structure and make better use of its resilience. For example, the containment of plastic hinge zones in reinforced concrete elements can be achieved by a carbon fibre reinforced polymer composite.

Composite reinforcements

Carbon fibre composite reinforcement is a proven solution to improve the resilience of reinforced concrete or masonry elements under earthquake conditions without adding mass and with only minor stiffening of the structure: (i) jacketing of beams and columns (ii) strengthening of walls in shear and flexure.
  • Strengthening beam-column joints
  • Confining plastic hinge zones
  • Column jacketing

Composite reinforcements

Carbon fibre composite reinforcement is a proven solution to improve the resilience of reinforced concrete or masonry elements under earthquake conditions without adding mass and with only minor stiffening of the structure: (i) jacketing of beams and columns (ii) strengthening of walls in shear and flexure.
  • Strengthening beam-column joints
  • Confining plastic hinge zones
  • Column jacketing
3. Isolating the superstructure from its substructure

The reduction of seismic action on a building can be achieved by dynamic isolation of its foundation structure. The isolator creates a frequency shift that works in the horizontal direction like a relatively low frequency oscillator.

Even after strong earthquakes, damage is limited and structures remain operational.

Seismic isolation

In the case of existing buildings, the insertion of seismic isolators requires disconnecting the superstructure from the substructure. The most common practice is to unload a column, cut it to insert an isolator, and then re-load it.
  • High damping rubber isolators
  • Rubber isolators combined with
    external damping devices
  • Pendulum bearings

Seismic isolation

In the case of existing buildings, the insertion of seismic isolators requires disconnecting the superstructure from the substructure. The most common practice is to unload a column, cut it to insert an isolator, and then re-load it.
  • High damping rubber isolators
  • Rubber isolators combined with
    external damping devices
  • Pendulum bearings

Discover our seismic retrofitting references

Repair
Philippines

Ayala bridge seismic protection upgrading

Significant savings in programme and budget were delivered when Freyssinet proposed an innovative rehabilitation scheme as an alternative to replacing this historic city-centre bridge in Manila.
Repair
Romania

Bucharest City Hall seismic protection

Bearings and dampers designed for seismic protection of an historic building in the city of Bucharest were so large they had to be shipped to a specialist laboratory in the USA to be tested.
Repair
Turkey

Marmara Hospital base isolation

Design and installation of base isolation measures for a hospital in Turkey had to address the fact that the building was made up of sixteen blocks, all of varying heights and dimensions.

Seismic retrofit for buildings -Download the brochure

Documentation
Documentation

Discover our ISOSISM range

Seismic protection

Pioneer in the development of earthquake protection devices, Freyssinet offers a complete range of dedicated products and associated services marketed under the well-known ISOSISM® brand.

Seismic protection

Pioneer in the development of earthquake protection devices, Freyssinet offers a complete range of dedicated products and associated services marketed under the well-known ISOSISM® brand.

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Our local experts will help you achieve your project thanks to our large range of solutions.
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You have a project?

Our local experts will help you achieve your project thanks to our large range of solutions.
Find your local contact

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