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Presentation of the SOCRAT Benchmark


This page provide a brief description of the mock-up and its instrumentation, and of one of the exercices asked. As a member of the Benchmark and member of this website, you will have access to the full descrition and data needed.

Description of the overhead crane bridge mock-up


The mock-up is a simplified 1/5 scaled model of a 22.5 m long overhead crane bridge. The diferent components of the mock-up are shown below:

  • Trolley

  • Rails

  • Wheels 

  • Girder beams

  • End truck beams

  • Runway beams

  • Load cells (included in the supports between the shaking table upper plate and the crane bridge mock-up)


© CEA, Saclay, France

As a member of the site and participant of the Benchmark, you will find all the information needed for the modeling of the mock-up on the page Members>The mock-up.


Different exercices are planned in order to characterize and calibrate the participants’ models, considering low and high seismic intensities signals, as well as hamer shock and white noise signals.

​Stage 1:

  • Exercice 1 - Siffness of the load cell block A

  • Exercice 2 - Runway beam 1

  • Exercice 3 - Crane bridge mock-up

  • Exercice 4 - Wheel/Rail interface

  • Exercice 5 - Friction coefficient and damping ratio

  • Exercice 6 - Local shocks parameters

  • Exercice 7 - High level calibration

For instance, the exercice 2 is given:

Run #

Analyse Type


Required Results

Exercice #2

Runway beam 1


Modal analysis

Free-free condition



first four;


(.png & vectors);


Modal analysis

Fixed condition



first four;


(.png & vectors);

17 (White noise signal)

Transient analysis



Acceleration: AxProule1H2;


Fx at supports A and B;

18 (White noise signal)

Transient analysis



Acceleration: AyProule1H2;


Fy at supports A and B;

19 (White noise signal)

Transient analysis



Acceleration: AzProule1H2;


Fz at supports A and B;

Girder beams


Girder beams are supporting the trolley. The provided

caracteristics are:

  • Rectangular hollow section

  • Length

  • Distance between their central axes

  • Young’s modulus  

  • Mass density  

  • Poisson’s ratio  

  • Yield stress  

girder beams.png

Instrumentation of the mock-up


The instrumentation dedicated to accelerations consists of 34 tri-axial accelerometers distributed on the mock-up and 4 tri-axial accelerometers on the shaking table, as follows:

  • Intermediate plates of a load cell block : 6

  • Base plates of the runway beams : 8

  • Runway beam 1 : 8

  • Runway beam 2 : 3

  • End truck beams : 2

  • Girder beam 1 and 2 : 6

  • Trolley : 1

  • Shaking table : 4

Runway beam 1

Two tri-axial accelerometers are placed at the ends of the runway beam 1. Six tri-axial accelerometers are distributed along the runway beam 1 on its upper and lower faces, precisely on the internal side of the rail since the cheeks of the wheels are placed on the outer side of the rail.

2 Tri-axial accelerometers





First end of the runway beam 1

Second end of the runway beam 1

6 Tri-axial accelerometers

AxProule1H1   AyProule1H1   AzProule1H1
AxProule1H2   AyProule1H2   AzProule1H2
AxProule1H3   AyProule1H3   AzProule1H3

AxProule1H1   AyProule1H1   AzProule1H1
AxProule1H2   AyProule1H2   AzProule1H2
AxProule1H3   AyProule1H3   AzProule1H3

Upper face of the runway beam 1

Lower face of the runway beam 1

runway beam 1.png
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