ARTeMIS User Training Course - Limited Seats Left!

This 2-days' course is for the new as well as experienced users that want to be updated on Operational Modal Analysis technology as well as the latest features of ARTeMIS Operational Modal Analysis software.

 

Venue

The course will be held on October 7-8, 2013 at Structural Vibration Solutions A/S, NOVI Science Park, Niels Jernes Vej 10, 9220 Aalborg East, Denmark. Both days we start at 9.00 and end at 16.00. There will be lunch and coffee breaks during the day and free WiFi internet access. The course instructor is Dr. Palle Andersen, CEO and senior developer of the ARTeMIS software.

 

 

Programme

On day 1 you will get a comprehensive introduction to Operational Modal Analysis technology in general. During this introduction, the differences to the well-known input/output modal analysis will be described. Also the procedures for acquiring high quality measurements will be discussed in detail. The introduction is followed by a presentation of the user-friendly Frequency Domain Decomposition (FDD) technique, and we will analyze some example data as hands-on exercises. Finally, the two other FDD related techniques of ARTeMIS (Enhanced Frequency Domain Decomposition and Curve-fit Frequency Domain Decomposition) are introduced, and we will continue with hands-on exercises using these techniques. The example data will both be from ambient excited structures and mechanical structures subjected to sinusoidal (harmonic) excitation. We end day 1 at a restaurant in the old downtown of Aalborg.

 

On day 2 you will be introduced to Stochastic Subspace Identification (SSI) and all the latest features being available in ARTeMIS.

 

You will get a binder with the course material as well as a 1-month free demo version of ARTeMIS Modal Pro, that we invite you to install on your own laptop for use during the hands-on exercises of the course.

 

Price

Attending the course will cost 895 EUR per person, and of course we give a 50% student discount. Book Now - Only Limited Seats Left!

 

Sign Up

Please download the registration form and send it by email to Structural Vibration Solutions at mo@svibs.com. We need your registration no later than September 23, 2013.

 

- Do you have an old version of the ARTeMIS Extractor? 

- Has your software maintenance expired?

Upgrade to the ARTeMIS Modal today - and get a Unique Campaign Offer!


Some of the new features with the ARTeMIS Modal:

• New ease-of-use and intuitive user interface that dramatically will shorten the learning curve
• Easier and faster signal processing and modal estimation
• New modal validation features
• Report generation through seamless integration with Microsoft Office products

Contact sales@svibs.com for further information.

 

 

Case Study: Austrian S101 Highway Bridge - Chapter 1

The information described in this case study is by courtesy of the European research projects “Integrated European Industrial Risk Reduction System (IRIS)” and “Internet based Structural Monitoring System (ISMS)”. Special thanks to H. Wenzel (VCE), M. Döhler (Inria), L. Mevel (Inria) and C.E. Ventura (UBC).

 

Objective

This case study demonstrates the use of the powerful Crystal Clear SSI of the ARTeMIS Modal Pro version. The measurements used are from the S101 highway overpass bridge located in Reibersdorf, Austria. The bridge crossed the national highway A1 Westautobahn Austria. It is a post-tensioned concrete bridge with a main span of 32 m, side spans of 12 m, and a width of 6.6 m. The deck is continuous over the piers and is built into the abutments. The bridge, built in 1960, had to be demolished due to some structural problems and to allow some space for additional lanes of the highway underneath.

 

     
 

Within the IRIS project, the bridge was artificially damaged in various ways. The damaging processes were accompanied by a permanent measurement of the static and dynamic behavior of the structure. Within the IRIS and the ISMS project, the acquired dynamic measurements have been used to validate the developed damage detection and damage localization techniques.

The objective of this first chapter is to describe the Operational Modal Analysis made in the reference state measurement performed before any damages were introduced. In the next chapter we will look at the results of the damage detection.

Measurement Campaign

The measurements were carried out by VCE and the University of Tokyo on December 10-13, 2008. The data acquisition system had 45 channels. The record length used in the present analysis was 1,815,009 samples acquired at 500 Hz. Total measurement time used in the analysis is as such just above one hour. All accelerometers were placed on the girder. Below the measurement setup can be viewed. The input configuration file was prepared by Prof. C.E. Ventura, UBC.

 

Signal Processing

The measurements were decimated from the original Nyquist frequency of 250 Hz to 25 Hz. The Automatic Projection Channel option was used, and it found 4 projection channels that in the following diagrams are highlighted in a magenta color. The Singular Values of the spectral densities reveal several distinct modes as seen below:

 

Modal Analysis

A quick analysis using the Enhanced Frequency Domain Decomposition method was used to get a "feeling" of what the measurements contained. It showed at least 5 distinct modes. After this the wokhorse of ARTeMIS Modal Pro - Crystal Clear SSI - was used with automatic settings. The Crystal Clear SSI was developed in 2010 in cooperation with the I4S Team at Inria. The stabilization diagram as well as the 6 modes the method found can be seen below:

 

Additional modes were identified, but were discarted due to too high Modal Complexity and unrealistic high damping.

 

The six modes of Crystal Clear SSI were validated against each other, and as seen below the Modal Assurance Criterion as well as the Modal Complexity show low correlation and low complexity:

 

 

The results were also validated by looking at the Cross Modal Assurance Criterion between Enhanced Frequency Domain Decomposition (EFDD) and Crystal Clear SSI (SSI-UPC). Here the superiority of SSI-UPC is revealed as EFDD is unable to find the first transverse mode and, in general, has a higher complexity for the high order modes. The cross validation is seen below:

 

 

 

The complete analysis, from data upload started to results were ready, took approx. 1 hour. The six modes are shown below and can be downloaded here in Universal File Format.

 

 

 

 

The modes will be used for updating of a FE Model of the structure. The updated model will then be used for damage localization later.

 

Related Information:

• M. Döhler, P. Andersen and L. Mevel: Operational Modal Analysis using a Fast Stochastic Subspace Identification Method
Proceedings of the 30th International Modal Analysis Conference (IMAC) Jacksonville, Florida USA, 2012.

• Wenzel, H. et al.: FP7-NMP-2007-LARGE-1 (IRIS) WP3 Demonstration Report, 2009

M. Döhler and L. Mevel. Fast multi-order computation of system matrices in subspace-based system identification. Control Engineering Practice, 20(9):882-894, 2012.

• M. Döhler, F. Hille, X.B. Lam, L. Mevel, W. Rücker
Confidence Intervals of Modal Parameters During Progressive Damage Test
Proceedings of the 29th International Modal Analysis Conference (IMAC) Jacksonville, Florida USA, 2011.

 


   


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