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:
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Trolley
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Rails
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Wheels
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Girder beams
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End truck beams
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Runway beams
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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.
Exercices
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:
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Exercice 1 - Siffness of the load cell block A
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Exercice 2 - Runway beam 1
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Exercice 3 - Crane bridge mock-up
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Exercice 4 - Wheel/Rail interface
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Exercice 5 - Friction coefficient and damping ratio
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Exercice 6 - Local shocks parameters
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Exercice 7 - High level calibration
For instance, the exercice 2 is given:
Run #
Analyse Type
Input
Required Results
Exercice #2
Runway beam 1
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Modal analysis
Free-free condition
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Eigenfrequencies:
first four;
Eigenmodes:
(.png & vectors);
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Modal analysis
Fixed condition
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Eigenfrequencies:
first four;
Eigenmodes:
(.png & vectors);
17 (White noise signal)
Transient analysis
Axtab1
Acceleration: AxProule1H2;
Force:
Fx at supports A and B;
18 (White noise signal)
Transient analysis
Aytab1
Acceleration: AyProule1H2;
Force:
Fy at supports A and B;
19 (White noise signal)
Transient analysis
Aztab1
Acceleration: AzProule1H2;
Force:
Fz at supports A and B;
Girder beams
Girder beams are supporting the trolley. The provided
caracteristics are:
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Rectangular hollow section
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Length
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Distance between their central axes
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Young’s modulus
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Mass density
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Poisson’s ratio
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Yield stress

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:
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Intermediate plates of a load cell block : 6
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Base plates of the runway beams : 8
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Runway beam 1 : 8
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Runway beam 2 : 3
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End truck beams : 2
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Girder beam 1 and 2 : 6
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Trolley : 1
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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
AxProule1H0
AyProule1H0
AzProule1H0
AxProule1H4
AyProule1H4
AzProule1H4
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
