Using Refined Simplified Model for Damage Detection in Offshore Jacket Structures

Authors

1 PHD candidate, Civil Engineering Department, University of Tabriz

2 Associate professor, Civil Engineering Department, University of Tabriz

3 Professor, Civil Engineering Department, University of Tabriz

Abstract

This work introduces a structural integrity assessment strategy for Jacket structures based on the finite element model updating and a novel simplified method. Hereof, model reducing and model updating procedure is established based on a optimization technique. Since the number of measured degrees of freedom is most of the time restricted in practice, this paper represents a methodology using the cross model cross mode method (CMCM) in combination with an iterative procedure which uses limited, spatially incomplete modal information. This research is an empirical study on a laboratory model of a jacket structure with the aim of establishing Refined Simplified FE Model (RSM) to conduct damage detection. In addition to elimination of uncertainty effects in the damage detection results, RSM technique is employed because of practical considerations and also this technique provides a fast damage zone diagnosis procedure. Also, improved reduction scheme is utilized based on static reduction scheme to carry out damage detection in jacket structure.

Keywords


[1] Asgarian, B., Aghaeidoost, V., Shokrgozar, H.R., “Damage detection of jacket type offshore platforms using rate of signal energy using wavelet packet transform”, Marine Structure, Vol. 45, pp. 1-21, 2016. [2] Wang, S.H., “Damage detection in offshore platform structures from limited modal data”, Applied Ocean Research, Vol. 41, pp. 48-56, 2013. [3] Caines, S., Khan, F., Shirokoff, J., Qiu, W., “Experimental design to study corrosion under insulation in harsh marine environments”, Loss Prevention in the Process Industries, Vol. 33, pp. 39-51, 2015. [4] Tang, Y., Qing, Z.H., Zhu, L., Zhang, R., “Study on the structural monitoring and early warning conditions of aging jacket platforms”, Ocean Engineering, Vol. 101, pp. 152-160, 2015. [5] Kuang, K.S.C., “Distributed damage detection of offshore steel structures using plastic optical fibre sensors”, Sensors and Actuators, Vol. 229, pp. 59-67, 2015. [6] Ji, C.Y., Xue, H.Z., Shi, X.H., Gaidai, O., “Experimental and numerical study on collapse of aged jacket platforms caused by corrosion or fatigue cracking”, Engineering Structures, Vol. 112, pp. 14-22, 2016. [7] Ren, W.X., Sun, Z.S., Xia, Y., Hao, H., Deeks, A.J., “Vibration-based damage identification of shear connectors in bridge decks: laboratory test study”, Journal of Structural Engineering, Vol. 134, pp. 832-841, 2008. [8] Chakraborty, S., Sen, A., “Adaptive response surface based efficient finite element model updating”, Finite Elements in Analysis and Design, Vol. 80, pp. 33-40, 2014. [9] Yuan, X.Z., Yu, K.P., “Finite element model updating of damped structures using vibration test data under base excitation”, Journal of Sound and Vibration, Vol. 340, pp. 303-316, 2015. [10] Kianian, M., Golafshani, A.A., Ghodrati, E., “Damage detection of offshore jacket structures using frequency domain selective measurements”, Marine Science and Application, Vol. 12, pp. 193-199, 2013. [11] Kaveh, A., Zolghadr, A., “An improved CSS for damage detection of truss structures using changes in natural frequencies and mode shapes”, Advances in Engineering Software, Vol. 80, pp. 93-100, 2015. [12] Kuang, K.S.C., “Distributed damage detection of offshore steel structures using plastic optical fibre sensors”, Sensors and Actuators, Vol. 229, pp. 59-67, 2015. [13] Farrar, C.R., Worden, K., “An introduction to structural health monitoring”, Phil. Trans. R. Soc. A, Vol. 365, pp. 303-315, 2007. (doi:10.1098/rsta.2006.1928) [14] Marwala, T., “Finite-element-model updating using computional intelligence techniques: Applications to structural dynamics”, Springer London Dordrecht Heidelberg New York., 2010. (DOI 10.1007/ 978-1-84996-323-7) [15] Farrar, C.R., Worden, K., “An introduction to structural health monitoring”, Phil. Trans. R. Soc. A, Vol. 365, pp. 303-315, 2007. (doi:10.1098/rsta.2006.1928) [16] Park, M., Koo, W., Kawano, K., “Dynamic response analysis of an offshore platform due to seismic motions”, Engineering Structures, Vol. 33, pp. 1607-1616, 2011. [17] Zhou, B., Han, X., Tan, S.K., “A simpliļ¬ed computational method for random seismic responses of a jacket platform”, Ocean Engineering, Vol. 82, pp. 85-90, 2014. [18] Hu, S.L.J., Li, H., Wang, S.H., “Cross-model cross-mode method for model updating”, Mechanical Systems and Signal Processing, Vol. 21, pp. 1690-1703, 2007. [19] Guyan, R.J., “Reduction of stiffness and mass matrices”, AIAA Journal, Vol. 3(2), p. 380, 1965. [20] Friswell, M.I., Mottershead, J.E., “Finite element model updating in structural dynamics”, Kluwer Academic Publishers, 1995. [21] Barltrop, N.D.P., Adams, A.J., “Dynamics of fixed marine structures”, Butterworth-Heinemann, Oxford, Third edition, 1991. [22] PULSE. Analyzers and solutions, release 11.2., “Denmark: Bruel & Kjaer”, Sound and Vibration Measurement A/S. Key code: 232072F0, 2006.