3DVISION MOTION CAPTURE SYSTEM AND THE DYSCO "VIRTUAL LABORATORY" FOR SEISMIC AND VIBRATION TESTS

Transcription

1 ATTIVITÀ IN CAMPO SISMICO RECENTI STUDI E SVILUPPI FUTURI Attività in campo sismico. 3DVISION MOTION CAPTURE SYSTEM AND THE DYSCO "VIRTUAL LABORATORY" FOR SEISMIC AND VIBRATION TESTS Gerardo De Canio,, Ivan Roselli

2 SUMMARY Introduction Seismic and vibration tests at UTT MAT-QUAL laboratory Data acquisition by 3DVision system DySCo virtual laboratory Real-time remote experimentation sharing Numerical simulation and computation Case Study: The Dome-Drum System of San Nicolò L Arena (CT) Conclusions

3 INTRODUCTION In the age of ICT, new technologies are becoming more and more available to keep remote engineers, researchers and students in contact for exchanging information on their scientific activities. A new Virtual Lab named DySCo (Structural Dynamics, numerical Simulation, Qualification tests and vibration Control) has been developing as a collaborative tool at UTT MAT-QUAL. DySCo can arise at a national level taking into account the collaboration between ENEA UTT MAT-QUAL and the Italian Network of University Laboratories of Seismic Engineering (ReLUIS). The web-based DySCo is intended to allow remote authorized partners in research projects (such as universities, research institutes, public and private bodies etc.) to attend seismic and vibration experiments conducted at ENEA UTTMAT-QUAL in real time.

4 SEISMIC AND VIBRATION TESTS AT ENEA ENEA UTT MAT-QUAL laboratory Shake tables and electrodynamic shakers: technical specification

5 DATA ACQUISITION BY 3DVISION SYSTEM Besides traditional sensors (accelerometers, LVDT) data acquisition is performed by 3DVision system which is able to track the dynamic displacement of several selected points (markers) of the structures during dynamic tests induced by shaking table. This innovative monitoring technique measures 3 axial absolute displacements with easy and fast test set-up, high accuracy. The 3D-motion time histories of the tracked markers can be linked with CAD drawings of the structure. The FE models can be validated in real time experimental data assimilation. The measure of the displacements is a crucial task for the numerical and experimental studies in structural dynamics, especially within the displacement based approach in seismic design and calculations.

6 DATA ACQUISITION BY 3DVISION SYSTEM Displacement measurement: 3DVision system NIR cameras configuration 3D reconstruction Geometrical triangulation of NIR cameras 3D reconstruction of markers complete motion 3D overlay of synchronized movies

7 DATA ACQUISITION BY 3DVISION SYSTEM Displacement measurement: 3DVision system 3D motion capture system, based on a constellation of 9 Near InfraRed (NIR) cameras Retro-reflecting markers are located on the measurement points of the mockup structure

8 DATA ACQUISITION BY 3DVISION SYSTEM Step 1: marker location Step 2: seismic tests Step 3: collapse

9 DYSCO VIRTUAL LABORATORY The possibility to synchronize visible and infrared cameras allows the remote participation to the shaking table tests in a networking configuration of distributed experiments within the virtual laboratory DySCo Home page: Authorized access to: Live lab tests Archived data and documents SW and computational tools

10 DYSCO VIRTUAL LABORATORY Definition of a virtual area where : All project partners can share Experimental Results in real time via Internet As the experimentation goes on, remote users interact step by step with the experts of DYSCO laboratory, to discuss and eventually modify the experimental test planning. Experimental data are saved and stored for future use in ENEA-DYSCO-Project database. Experimental data are available and editable according to different permissions (by different user s privileges). Definition of an educational area for University students where tutorials, documentation, papers, reports, 3DVison images and films are available

11 DYSCO VIRTUAL LABORATORY Connection to the ENEA-DYSCO laboratory is provided by: CRESCO (Computational RESearch on COmplex system connection) facilities via ENEA-GRID ENEA-Grid AFS File sharing system : AFS makes easy for projects partners to work together on the same files Partners always identify a file by the same pathname, and AFS finds the correct file automatically AFS does not compromise the security of the shared files Each project partner has his own afs account Different accounts could be located in the same project directory (folder) with different privileges (different editing/writing/reading permissions) ENEA-GRID and CRESCO facilities give the remote user the capabilities of parallel computation and the opportunity to run structural analysis of heavy finite element models.

12 DYSCO VIRTUAL LABORATORY Technical specifications High Performance Computing (HPC) infrastructures of CRESCO is provided with a cluster subdivided into several sections Computational resources: up to 28 Tflops Graphic section: 12 workstations or nodes (68 cores) Storage system: direct access to the AFS and to the General Parallel File Systems (GPFS) with High speed storage 2 GByte/s and 160 TByte. Also, the storage system is provided with a centralized backup system Internet connection: is performed through the Italian Academic & Research Network (GARR) by two lines of 1000 Mbits

13 REAL-TIME REMOTE EXPERIMENTATION SHARING AFS (Andrew File System) AFS is a distributed file system that joins together the file systems of multiple file servers. A distributed file system has two main advantages over a conventional centralized file system: Increased availability: copies of files can be stored on many file servers. User requests for the file or application are routed to accessible servers Increased efficiency: the workload is distributed over many smaller computers, which can be more fully utilized than the larger, and usually more expensive, file storage computer of a centralized file system AFS identifies users as authenticated users by a username and password. AFS uses an Access Control List (ACL) to determine who can access an AFS directory and what actions they can perform on its files.

14 REAL-TIME REMOTE EXPERIMENTATION SHARING

15 REAL-TIME REMOTE EXPERIMENTATION SHARING

16 NUMERICAL SIMULATION AND COMPUTATION FARO functionalities: Search for required applications Selection of data Export of data Direct access to the grid resources ENEA-GRID job submission Data Security is assured by ssh tunnel (safe access to the resources even from outside the ENEA network) Data flow and quality/compression rate are optimized depending on the band available at the request time, consequently theoretically from any access point of the network.

17 NUMERICAL SIMULATION AND COMPUTATION

18 NUMERICAL SIMULATION AND COMPUTATION FE codes available in ENEA GRID for structural analysis: ABAQUS, MARC: especially used for non-linear analysis ANSYS, NASTRAN: general purpose codes especially used for linear, non linear, thermal, acoustic, mechanical analysis. FLUENT, STARCD, MpCCI: fluid dynamic code GAMBIT, MENTAT, PATRAN: pre-post processors MENTAT: pre-post processor DYTRAN: explicit code for impact simulation. MDDAM: for Dynamic Response Spectrum and Shock Analysis. MDLINEARCONCTAT: especially used to simulate permanent glue contact MDACUSTIC: for acoustic application

19 CASE STUDY: THE DOME-DRUM SYSTEM OF SAN NICOLÒ L ARENA(CT) Shaking table tests was conducted on a 1:6 scaled mock-up representing the dome-drum system. The mock-up is in typical ashlar tuff masonry with a roof and a footing in R.C. The stress-strain distribution resulting from FEA allowed to identify the most adequate positions for the markers of 3DVision system. The Umbria-Marche earthquake registered in Colfiorito in September 1997 (Sabetta et al. 1999) was considered as reference for the scaled input time history. Material properties were preliminary evaluated by literature and updated by non destructive sonic tests.

20 CASE STUDY: THE DOME-DRM SYSTEM OF SAN NICOLÒ L ARENA (CT) Finite Element Modeling and Analysis Pre-post processing: Patran 3D Model: 2648 elm Hexa 8 Analysis Solver: Nastran Static and dynamic and linear transient analysis Distributed mass: 88 KN (on the top of the model)

21 CASE STUDY: THE DOME-DRUM SYSTEM OF SAN NICOLÒ L ARENA(CT) FEA resonance frequencies and modal shapes Shear type mechanism Twisting mechanism I-II Mode: 3.8 Hz III Mode: 6.9 Hz

22 CASE STUDY: THE DOME-RUM SYSTEM OF SAN NICOLÒ L ARENA (CT) Stress-Strain FE distribution 3D-Vision markers

23 CASE STUDY: THE DOME-DRUM SYSTEM OF SAN NICOLÒ L ARENA(CT) 3DVision results and model updating 3D-Vision D1S marker = FEA 4841 node Colfiorito Input time-history

24 CASE SUDY: THE DOME-DRUM SYSTEM OF SAN NICOLÒ L ARENA (CT) Comparison between FEA and 3D-Vision: absolute displacements results The displacement increase from the bottom to the top of the model agrees with experimental tests. Elastic-cracking behavior with limited tensile strength of the masonry and with the path of the fractures proceeding also from the bottom to the top of the mock-up New dissipative elements inserted on the damaged structure to improve the seismic behaviour and experimental tests re-executed Experimental results shared in real time via Internet

25 CASE SUDY: THE DOME-DRUM SYSTEM OF SAN NICOLÒ L ARENA (CT) Comparison between FEA and 3D-Vision: FEM node = 3DVision marker

26 REAL-TIME REMOTE EXPERIMENTATION SHARING control console

27 CONCLUSIONS DySCo virtual lab allows immediate fruition of experimental tests via the Internet from remote sites. 3D-Vision system proved to be very effective in sharing UTT MAT-QUAL experimentation tests Research cooperation and dissemination are optimized Cost reduction of experimental campaign on the part of remote partners. Archived data can be processed and FE analysis can be performed by ENEA-CRESCO facilities for numerical computation. UTTMAT-QUAL security and safety policy is to let control of laboratory instrumentation under local staff only. DySCo is the result of the collaboration between two ENEA different work-teams: UTT MAT-QUAL and UT-ICT-HPC

28 Thank you for your kind attention!