Fire, thermal & diffusion

You are confronted with a fire or a freeze-thaw climatic variation? You are in the construction phase of a reinforced concrete structure? You have a problem of mechanical resistance and waterproofing of the walls?

We can accompany you and help you find the solution.

Complex structural efforts

Structures can be subject to geometric variations of thermal origin such as expansion or contraction. They can also undergo drying (desiccation of concrete) or creep problems. This often leads to the degradation of mechanical properties such as fire resistance.

These efforts are complex subjects not always handled by engineers. Moreover, the calculation software treats these phenomena in a simplified way.

These phenomena are important and can impact both new designs and the re-evaluation of existing projects.


Two types of studies for each situation

Simplified studies that are carried out in the feasibility phase or preliminary opinion.

Detailed studies are carried out with multiphysical modelling to meet a wide range of requirements.

  • Evaluation of the duration of fire stability and prediction of the failure mode
  • Verification of the watertightness of a tank or containment with consideration of the creep and desiccation shrinkage of pre-stressed reinforced concrete
  • Taking into consideration the thermal load of climatic origin in the dimensioning of the structural elements of a building: facade, acroterion, thermal bridge breakers
  • Development of a cooling device for a solid concrete structure to avoid excessive heating of the concrete with the risk of cracking after thermal shrinkage or activation of the ASR (alkali sulfate reaction)

At Sixense necs, our solutions are practical and certified

We master the physical models that describe these phenomena and their interactions.

We exploit all the regulatory possibilities such as Eurocodes or Code Model.

Each methodology used is calibrated and validated by current regulations and experimental tests.

We are modeling these phenomena using the finite element method.

Our references

They trusted us

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