Seismic Reliability of Steel Frames Systems Equipped with Viscose Dampers

Document Type : Articles

Authors

Faculty of Engineering, Kharazmi University, Tehran, Iran

Abstract

Structures may undergo unexpected changes during the construction and assembly of materials and their sections, or may be affected by earthquakes of various magnitudes and mechanisms during their life time. Each of these changes may affect the possibility of structural failure. These variable parameters are examined as reliability. By the theory of reliability, uncertainties of the structural and non-structural parameters such as material properties, geometrical dimensions, and seismic inputs, etc. are taken into account. The theory of reliability with fragility curves shows which part of the model is more affected by uncertainties. These curves show the probability of passing a certain level of damage against seismic parameters.
This paper presents a reliability analysis of the steel moment resistance structure equipped with viscous dampers applied by uncertainties in seismic input and structural properties such as ductility and fragility of beam and column, damping coefficient of dampers by obtaining fragility curves. Given the intensity and frequency of near-field earthquakes that cause large displacements in the structure and it is possible that the braces on which the dampers are mounted enter the nonlinear domain before activating or collapse of viscous damper, the analysis are examined only on the basis of far field earthquakes. Nonlinear incremental dynamic analysis (IDA) is applied to the 5 and 10-story frames modeled in OpenSees software under a set of 22 pairs of acceleration records. Also, to reduce the time and number of analyzes, the response level method has been used in this study. The number of scenarios required for the response level method is obtained from the box-Wilson method. According to the results obtained from the analyzes (mean and deviation from the failure level criterion), a second-degree surface procedure for mean and standard deviation has been internalized. The Monte Carlo method also simulated 10,000 fragility curves to determine the final fragility curve. The results show that increasing structural story has a significant effect on the uncertainty in the response of structures. Based on the results, considering uncertainties in 5 and 10-story structure reduce failure spectral acceleration (Sa) by 7.1% and 9.3% respectively. Besides, in spectral values corresponding to the first mode of 5 and 10-story structures, with considering the uncertainty, probability of failure increase about 52.4% and 74.7%, respectively. The results showed that considering the uncertainty in some parameters increases and others reduce the capacity of the structure; however, by considering uncertainty in all mentioned parameters simultaneously, it will reduce the capacity and increase the probability of collapse.

Keywords


1.    Moehle, J. and Deierlein, G.G. (2004) A framework methodology for performance-based earthquake engineering. 13th World Conference on Earthquake Engineering, 679.
2.    Rahimi, S. and Nemati, M. (2015) Introduction to Reliability Methods and its Applications in Structural Engineering. First National Conference on Applied Research in Civil Engineering (in Persian).
3.    Rezaei, F., Gerami, M., and Naderpour, H. (2017) Evaluation of seismic reliability of steel moment resisting frames rehabilitated by concentric braces with probabilistic models. Journal of Structural and Construction Engineering (JSCE), 4(2), 5-18 (in Persian).
4.    Liel, A.B., Haselton, C.B., Deierlein, G.G., and Baker, J.W. (2009) Incorporating modeling uncertainties in the assessment of seismic collapse risk of buildings. Structural Safety, 31(2), 197-211.
5.    Altieri, D., Tubaldi, E., Patelli, E., and Dall’ Asta, A. (2017) Assessment of optimal design methods    of viscous dampers. Procedia Engineering, 199, 1152-1157.
6.    Guo, A., Xu, Y., and Wu, B. (2002) Seismic reliability analysis of hysteretic structure with viscoelastic dampers. Engineering Structures, 24(3), 373-383.
7.    Mahsuli, M. (2012) Probabilistic Models, Methods, and Software for Evaluating Risk to Civil Infrastructure. University of British Columbia.
8.    Mahsuli, M. and Haukaas, T. (2013) The Computer Program Rt. (The University of British columbia) Retrieved: http://terje.civil.ubc.ca/the-computer-program-rt/.
9.    Mahsuli, M. and Haukaas, T. (2012) Computer program for multimodel reliability and optimization analysis. Journal of Computing in Civil Engineering, 27(1), 87-98.
10.    Dall’Asta, A., Scozzese, F., Ragni, L., and Tubaldi, E. (2017) Effect of the damper property variability on the seismic reliability of linear systems equipped with viscous dampers. Bulletin of Earthquake Engineering, 15(11), 5025-5053.
11.    Agency, F.E. (2009) Quantification of Building Seismic Performance Factors. FEMA P695.
12.    Maniei, S., Sarvoghad moghaddam, A., and Ghafouri ashtiani, M. (2016) Probabilistic Assessment of the Asymmetric Collapsing Short Buildings in the Plan. Bulletin of Earthquake Science and Engineering, 3(2), 47-69, (in Persian).
13.    Karavasilis, T.L. (2016) Assessment of capacity design of columns in steel moment resisting frames with viscous dampers. Soil Dynamics and Earthquake Engineering, 88, 215-222.
14.    Karavasilis, T. and Konstantinos, K. (2019) Limits for the interstorey drift sensitivity coefficient θ of steel MRFs with viscous dampers designed according to Eurocode 8. Dynamics and Earthquake Engineering, 117, 203-215.
15.    Agency, F.E. (2003) HAZUS-MH MR4 Technical Manual. National Institute of Building Sciences and Federal Emergency Management Agency (NIBS and FEMA), 213.
16.    Agency, F.E. (2000) Recommended Seismic Design Criteria for New Steel Moment-Frame Buildings. FEMA350, 196.
17.    Vamvatsikos, D. and Cornell, C.A. (2004) Applied incremental dynamic analysis. Earthquake Spectra, 20(2), 523-553.‏
18.    Bucher, C.G. and Bourgund, U. (1990) A fast and efficient response surface approach for structural reliability problems. Structural Safety, 7(1), 57-66.
19.    Myers, R.H. and Carter, W.H. (1973) Response surface techniques for dual response systems. Technometrics, 15(2), 301-317.
20.    Zhang, Z.Y., Huang, W.B., Zhou, Y.F., and Song, T.S. (2012) Seismic reliability analysis of complex structure. Advanced Materials Research, 446, 2321-2325. Trans Tech Publ.
21.    Lignos, D.G. and Krawinkler, H. (2011) Deterioration modeling of steel components in support of collapse prediction of steel moment frames under earthquake loading. Journal of Structural Engineering, 137(11), 1291-1302.
22.    Wolfe, R., Yun, H.B., Masri, S., Tasbihgoo, F., and Benzoni, G. (2008) Fidelity of reduced‐order models for large‐scale nonlinear orifice viscous dampers. Structural Control and Health Monitoring: The Official Journal of the International Association for Structural Control and Monitoring and of the European Association for the Control of Structures, 15(8), 1143-1163.