27 VCE_EuropaBrücke
Transcript
27 VCE_EuropaBrücke
SAMCO Final Report 2006 F04 Case Studies Europabrücke - Austria Project Description: Bridges are ageing and traffic is growing, which creates a demand for accurate fatigue life assessment. The Europabrücke – a well known Austrian steel bridge near Innsbruck, opened in 1963 - is one of the main alpine north-south routes for urban and freight traffic. A long-term preoccupation of VCE with BRIMOS (BRIdge MOnitoring System) on the Europabrücke (since 1997) and the assessed prevailing vibration intensities with regard to fatigue problems and possible damage led to the installation of a permanent measuring system in 2003. Today’s monitoring abilities enable us to measure performance precisely. High-precision sensor data of accelerations, velocities, displacements in dependence of separately registered wind and temperature data and their implementation into analytical calculation provide the possibility to realize lifetime considerations, which are of eminent importance for bridge operators. Europabrücke, Innsbruck, Austria Description of Structure & Monitoring System Previous measurements at the Europabrücke matched very well with the comparative analytical calculations, but they also exhibited the remarkable loading impact. Currently the bridge is stressed by more than 30000 motor vehicles per day (approximately 20% freight traffic). The superstructure is represented by a steel box girder (width = 10m; variable height along the bridge-length 4,70 – 7,70 m) and an orthotropic deck and bottom plate. This motorway bridge with six spans differing in their length (longest span 198m, supported by piers with an elevation of 190m) and a total length of 657 m comprises six lanes, three for each direction distributed on a width of almost 25 meters. www.samco.org Page 1 of 6 SAMCO Final Report 2006 F04 Case Studies Quick Facts: • Name and Location: Europabrücke, Innsbruck, Austria • Operator: ASAG (Alpenstrassen AG), Austria • Structure category: large span bridge • Spans: 6 spans: 81/ 108/ 198/ 108/ 81/ 81 m • Structural system: Steel box girder with orthotropic deck and concrete columns • Start of SHM: May, 1998 • Number of sensors installed: 24 • Instrumentation design by: VCE, Vienna Consulting Engineers, Austria The monitoring system itself consists of 24 measuring channels (sampling rate 100 Hz) representing the main span’s, the pier’s and the cantilever’s accelerations, the abutment’s dilatation, wind speed and direction, and temperatures at several locations. WL PATSCH WL SCHÖNBERG Purpose of Inspection: The superior goal is to determine the relation between the randomly induced traffic loads (vehicles per day) and the fatigue-relevant, dynamic response of the structure. As life-time predictions in modern standards depend on lots of assumptions, the emphasis is to replace all these guesstimates by measurements. In that context it is going to be focused on three ranges: • • • Global behavior in dependence of all relevant loading cases Cross-sectional behavior under special consideration of the cantilever regions Local systems analyzing the interaction between tires and the beam-slab connections www.samco.org Page 2 of 6 SAMCO Final Report 2006 F04 Case Studies In each of these levels of analysis the consumption of the structure’s overall-capacity per year is to be determined. Additionally to fatigue assessment, new compensation methods for assessment & compensation of environmental conditions (temperature, additional mass loading,…) in frequency analyses are developed. This opens new possibilities for structural management and lifetime prediction as well as for more accurate damage detection. Sensor Details: Type of sensors Number Location Displacement sensors 2 at both abutments 1D-acceleration transducers 3 at the cross section’s cantilevers 3D-acceleration transducers 3 orthotropic bottom plate Wind sensors 1 5m above the road surface Temperature sensors 7 inside & outside the box girder Measurement Equipment and Data Management: Type of system PC & remote access - based measuring system Data Management automatic report generating at the end of each week Storage in a long term data base on site More detailed analysis (statistics, frequency analysis…) and graphical presentation and documentation in office notification via modem about the successful operation of the measuring system Data Analysis Procedures: Type of analysis Ambient vibration monitoring, Fatigue assessment based on rainflow analysis & statistics, assessment & compensation of environmental conditions, damage detection and lifetime calculations www.samco.org Software Additional features Self made software, RFEM no expert system Page 3 of 6 SAMCO Final Report 2006 F04 Case Studies Examples of Outcomes - Assessment & Compensation of Environmental Conditions 1. Eigenfrequency Temperature 00:00:00 00:00:00 Time 22:00:00 22:00:00 20:00:00 20:00:00 18:00:00 18:00:00 16:00:00 16:00:00 14:00:00 14:00:00 12:00:00 12:00:00 10:00:00 10:00:00 08:00:00 08:00:00 06:00:00 06:00:00 04:00:00 04:00:00 02:00:00 Time 02:00:00 [°C] [Hz] 00:00:00 00:00:00 0,710 0,720 0,730 0,740 0,750 0,760 0,770 0,0 5,0 10,0 15,0 20,0 25,0 Pattern of the main span’s stiffness and its obvious dependency on temperature (daily cycle) Temperature - Base Point - box girder (from 07-03-2003 until 20-05-2005) [°C] 38 33 28 23 18 13 8 3 -2 -7 Max = +36,25 °C Min = -15,58 °C -12 (04-08-2003) (01-03-2005) 25.04.2005 26.03.2005 24.02.2005 25.01.2005 26.12.2004 26.11.2004 27.10.2004 27.09.2004 28.08.2004 29.07.2004 29.06.2004 30.05.2004 30.04.2004 31.03.2004 01.03.2004 31.01.2004 01.01.2004 02.12.2003 02.11.2003 03.10.2003 03.09.2003 04.08.2003 05.07.2003 05.06.2003 06.05.2003 06.04.2003 07.03.2003 -17 Pattern of temperature at the bridge’s basing point (assessment period 2 ½ years) mm Vergleich der gemessenen und rechnerischen Verschiebung ∆u an der DMA1 Europabrücke vom 05.03.2004 - 20.05.2005 100,00 40 30 50,00 20 0,00 10 -50,00 0 -100,00 -10 ∆u gem. korr. Hüllkurve unten Hüllkurve oben Temperatur Hohlkasten -20 05.03.2004 12.03.2004 19.03.2004 26.03.2004 02.04.2004 09.04.2004 16.04.2004 23.04.2004 30.04.2004 07.05.2004 14.05.2004 21.05.2004 28.05.2004 04.06.2004 11.06.2004 18.06.2004 25.06.2004 02.07.2004 09.07.2004 16.07.2004 23.07.2004 30.07.2004 06.08.2004 13.08.2004 20.08.2004 27.08.2004 03.09.2004 10.09.2004 17.09.2004 24.09.2004 01.10.2004 08.10.2004 15.10.2004 22.10.2004 29.10.2004 05.11.2004 12.11.2004 19.11.2004 26.11.2004 03.12.2004 10.12.2004 17.12.2004 24.12.2004 31.12.2004 07.01.2005 14.01.2005 21.01.2005 28.01.2005 04.02.2005 11.02.2005 18.02.2005 25.02.2005 04.03.2005 11.03.2005 18.03.2005 25.03.2005 01.04.2005 08.04.2005 15.04.2005 22.04.2005 29.04.2005 06.05.2005 13.05.2005 20.05.2005 -150,00 Comparison of assessed & expected horizontal bridge deformations in dependence of temperature www.samco.org Page 4 of 6 SAMCO Final Report 2006 F04 Case Studies Wind velocity-analysis for a certain month In each of the already described levels of fatigue analysis performed by means of Rainflow-Counting, damage-accumulation, global and local Finite Element Analysis & statistical consideration. The detailed knowledge about the progression of the prevailing traffic from the very beginning up to these days and the implementation of published future trend studies for the next ten years can be used for an extrapolation of the measured impact for the whole lifetime. mm 17.52 27161 10000 Ereignisse (logarithmisch) 27161 10000 1000 1000 Min 100 0 10 1 17.52 -17.52 mm mm 0 0 Min Max -17.52 17.52 -17.52 17.52 1 8 2 2 5 2 1 2 + 50 + 39 + 24 + 20 + 17 + 9 + 8 + 6 + 5 + 3 + 1 3 + 5 + 4 + 4 1 100 + + + + + + + + + + + + + + + + + + + + + 9478 66 90 + + + 2720 21 19 + + + + 1812 2 8 28 + + + + 4 1 4 4 5 + + + 9678 3 3 2 2 15 + + 7859 60 2 1 1 2 + 66 6551 2923 1 1 18 + + + 8755 50 10 1 0 -17.52 Max mm Rainflow Matrices for counting of recurring fatigue-relavant impact cycles Damage assessment via implementation of measurements into Finite Element-Models www.samco.org Page 5 of 6 SAMCO Final Report 2006 F04 Case Studies References 1. Wenzel, H., and D. Pichler. 2005. “Ambient Vibration Monitoring,” J. Wiley and Sons Ltd., Chichester - England, ISBN 0470024305 2. Veit R., H. Wenzel and J. Fink. 2005. “Measurement data based lifetimeestimation of the Europabrücke due to traffic loading - a three level approach”, In International Conference of the International Institute of Welding. Prague. 3. H. Wenzel, R. Veit, H. Tanaka.: “Damage detection after condition compensation in frequency analyses” in “Proceedings of the 5th International Workshop on Structural Health Monitoring”, Stanford, September 2005 Submitted by: Vienna Consulting Engineers (VCE) A-1140 Vienna, Austria 60 Hadikgasse Phone: +43(1) 8975339-1420 Fax: +43(1) 8975339-2420 Email: [email protected] www.samco.org Page 6 of 6