April 2019

  • LinkedIn Social Icône
  • YouTube Social  Icon
  • Facebook Social Icon

> Rincent ND Applications, a specialist in non-destructive testing, and Rincent Alpes, have carried out non-destructive dynamic tests on existing anchoring rods on the tie beam of a cabin cableway support tower in the Mont Blanc massif.

The investigation focused on:

> the length of the elements

> the dynamic stiffness, related to the inertia   of    the    element     tested    in    its environment and to the existing tension force.

The tests implemented consist of:

> to vibrate the anchoring rod with an impact caused in the direction of its axis; this   impact   is    caused    by    a   hammer equipped with a force sensor,

> to record the vibration V of the anchoring rod   using   a   speed   sensor  fixed  on the support plate,

> to analyze the Speed / Force curve as a function     of     the      frequency     after    a mathematical treatment of these signals.

The equipment is semi-annually audited as per the test standard. The analysis of the curve focuses on:

> the frequency response,

> the value of the dynamic stiffness.

The frequency response allows the calculation of:

> the total length of the anchoring rod

> in some configurations the "free" length,

> or other singularities.


Dynamic stiffness is the modulus of a complex number which is inversely proportional to the slope at the origin of the V / F curve as a function of frequency.

The stiffness characterizes the operation of the anchoring rod.

The work   of    Rincent  Laboratoires    on   the determination of efforts in the anchoring rods from dynamic stiffness®    is   the   result  of    a theoretical research that resulted in the filing of an international patent. The tests carried out for more    than    20    years    constitute   a    strong experience  in  the  field,  however  a database is totally insufficient to interpret these tests.

Rincent BTP Services SAS

4 bis rue du Bois Briard

91080 Courcouronnes

Tél. +33 1 60 87 21 25

© 2020 Rincent Laboratoires