Continuous ambient vibration measurements: experimental setup and first results on an arch dam


• Regarding intraday behaviour, the effect of the sunshine is clearly seen during summer and additional analyses should be carried out to evaluate the interest of such behaviour.


• Looking at the evolution of the frequencies for 1 year (Figure 12), there is clearly a change of behaviour during wintertime from mid-November to the end of April with much more instability of the frequencies


compared to the rest of the year. While frequency variation is generally in line with temperature variation during the rest of the year, this relation becomes the opposite in winter.


Additional measurements in winter 2024-2025 along with daily remote monitoring of the pendulums should allow to better understand this behaviour.


REFERENCES


[1] Oliveira, S. et al. (2024). Cahora Bassa vibrations monitoring between 2010-2022. Analysis of frequencies using HST statistical models for effects separation, Journal of Physics: Conference Series 2647.


[2] Darbre, G. et al. (2002). Continuous ambient-vibration monitoring of the arch dam of mauvoisin, Earthquake Engng Struct. Dyn. 31:pp.475-480.


[3] Ueshima T. et al. (2017) Structural health monitoring of an aged arch dam using long term contiuous observation of ambient vibration /seismic motion, 16th WCEE Santiago Chile


[4] Bukenya, P., Moyo P et al., Long term integrity monitoring of a concrete arch dam using continuous dynamic measurements and a multiple linear regression model, International symposium of SANCOLD, Johannesburg, 2016


[5] Humbert, N. & Robbe E. (2023). Ambient Vibration: Feedbacks from Measurements on 20 Concrete Dams and Comparisons with Finite-Element Analyses.Focus on One Year of Recording on an Arch, Proceedings EVACES 2023.


[6] Martin, N. et al. (2021). Automated machine health monitoring at an expert level, Acoustics Australia, Special issue on Machine condition monitoring.


[7] Van der Auweraer, H., Peeters, B. et al. (2001). “PolyMAX: A Revolution in Operational Modal Analysis.” Presented at the IMAC Conference on Structural Dynamics.


[8] Peeters, B. et al. (2004). “A New Procedure for Modal Parameter Estimation” International, Leuven, Belgium


[9] Balmes, E. “Frequency domain identification of structural dynamics using the pole/residue parametrization.” International Modal Analysis Conference, Dearborn, 1996


[10] Balmes, E. “New results on the identification of normal modes from experimental complex modes” - Mechanical Systems and Signal Processing, 1997.


Vol XXXIII Issue 3 | Dam Engineering | 155


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100