Inferring Dynamic Characteristics of a Bridge through Numerical Simulation and and Low-Magnitude Shaking as a Global NDE Method
Conference: Publication Date: 26 August 2018
Boundary conditions of a structure affect its response to dynamic excitations. In most highway bridge designs, the dynamic soil-structure interaction is not considered, with an underlying assumption that bridge piers have fixed-ends. Foundation flexibility, and more importantly radiation damping from the foundation, whether it is a shallow or deep foundation, can significantly influence the response of substructure/superstructure system. This may lead to deviations of the actual response compared to the design assumptions, depending on soil properties and geometrical and structural characteristics of the bridge. Low-magnitude shaking can be used as the means of evaluation of actual dynamic characteristics of a bridge. Moreover, numerical simulations of the same bridge with the same low-magnitude shaking load on the bridge can be used to model the dynamic response of the bridge, with the consideration of the dynamic soils structure interaction. In this paper, a comparison between the actual response of a bridge in Hamilton Township, New Jersey, and results from numerical simulations is presented. The shaking of the bridge was done using T-Rex, a large mobile shaker from NHERI Experimental Facility at University of Texas at Austin. The test setup, and results from both numerical simulations and field-testing are presented and discussed. Experimental results confirm that the FEM model developed is adequate to infer dynamic characteristics through the eigenmode analysis.
- Catbas, F.N. and T. Kijewski-Correa, “Structural Identification of Constructed Systems: Collective Effort toward an Integrated Approach That Reduces Barriers to Adoption,” Journal of Structural Engineering, 2013, 139(10): p. 1648-1652.
- Antonellis, G. and M. Panagiotou, “Seismic Response of Bridges with Rocking Foundations Compared to Fixed-Base Bridges at a Near-Fault Site.” Journal of Bridge Engineering, 2014, 19(5).
- Nikolaos, L., S. Anastasios, and K. Oh-Sung, “Influence of frequency-dependent soil– structure interaction on the fragility of R/C bridges,” Earthquake Engineering & Structural Dynamics, 2017. 46(1): p. 139-158.
- A.G. Sextos and G.D. Manolis, “Dynamic Response of Infrastructure to Environmentally Induced Loads,” 1 ed. Lecture Notes in Civil Engineering, 2017.
- Bao, Y., Guanlin, Y., Bin, Y., and Feng, Z., “Seismic evaluation of soil– foundation– superstructure system considering geometry and material nonlinearities of both soils and structures,” Soils and Foundations, 2012. 52(2): p. 257-278.
- Brownjohn, J.M.W., M., Boccioloneb, A.,Curamib, M.,Falcob, and A., Zassob., “Humber bridge full-scale measurement campaigns 1990– 1991”, Journal of Wind Engineering and Industrial Aerodynamics, 1994. 52: p. 185-218.
- Yarnold, M.T. and F.L. Moon, “Temperature-based structural health monitoring baseline for long-span bridges. Engineering Structures”, Engineering Structures, 2015. 86: p. 157-167.
- Moon, F.L. and A.E. Aktan, “Impacts of Epistemic (Bias) Uncertainty on Structural Identification of Constructed (Civil) Systems,” The Shock and Vibration Digest, 2006. 38(5): p. 399-420.
- Menq, F.Y., K. H Stokoe, K. I. Park, B. Rosenblad, and B. R.Cox, “Performance of Mobile Hydraulic Shakers at NEES@UTexas for Earthquake Studies,” presented at the 14th World Conference on Earthquake Engineering, Beijing, China, 2008.
- Stokoe, K., B. Cox, P.Clayton, and F.Y. Menq, “NHERI@UTexas Experimental Facility: Large-Scale Mobile Shakers for Natural-Hazards Field Studies,” presented at the 16th World Conference on Earthquake Engineering, Santiago, Chile, 2017.
- Gazetas, G., “Formulas and Charts for Impedances of Surface and Embedded Foundations," Journal of Geotechnical Engineering, 1991. 117(9): p. 1363-1381.
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