The Effect of Height of Structure on the Accuracy of Nonlinear Static Analysis Methods in Steel Structures with Lead Rubber Bearing (LRB) Base Isolators

Document Type : Original Article

Authors

1 Faculty of Engineering, Mahallat Institute of Higher Education, Mahallat, Iran

2 Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran

3 Faculty of Technical and Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran

Abstract

In this study, a comparative study of non-linear static methods with time history method for Chevron braced structures (with LRB seismic base isolator at the base level) is performed. To find out the effect of the building's height on seismic responses of isolated structures, in this study 3 isolated building structures by LRB isolators with 3 different number of stories of 4, 7 and 10, located in a high seismicity area have been modeled in 3D by assuming the soil type C. Pushover non-linear static analysis procedures, with target displacements according to ASCE41-13 code and using three lateral load patterns, including structure's first mode, uniform and triangular have been analyzed using spectral dynamic, PSC and the results have been compared with those of non-linear dynamic analysis subjected to selected far-field earthquakes. The results show that in the estimation of maximum displacement of LRB isolators and also the amount of base shear, ASCE41-13 has a high degree of accuracy in structures with different heights. In estimating the displacement of maximum floors, first mode methods, uniform, spectral dynamic have had enough accuracy in all discussed heights. In estimating the relative displacement of structures' floors, by increasing the height of the structure, the accuracy of the triangular load's pattern reduces significantly. In contrast with it, the PSC method has high accuracy.

Keywords

Main Subjects

References

[1] Tanwer, M. T., Kazi, T. A., & Desai, M. (2019). “A Study on Different Types of Base Isolation System over Fixed Based”, In Information and Communication Technology for Intelligent Systems, 725-734.
[2] Cancellara, D., & De Angelis, F. (2016). “A base isolation system for structures subject to extreme seismic events characterized by anomalous values of intensity and frequency”, Composite Structures, 157, 285-302 
[3] Tepes, O. F., & Ene, M. (2015). “Non-Linear Structural Analysis of Structures that Include Load-Bearing Walls Based on Performance Criteria”, Buletinul Institutului Politehnic din lasi. Sectia Constructii, Arhitectura, 61(2), 85.
[4] Providakis, C. (2008). “Effect of LRB isolators and supplemental viscous dampers on seismic isolated buildings under near-fault excitations”, Engineering Structures, 30(5), 1187-1198. 
[5] Fajfar, P. (2000). “A nonlinear analysis method for performance-based seismic design”, Earthquake spectra, 16(3), 573-592. 
[6] Providakis, C. (2008). “Pushover analysis of base-isolated steel–concrete composite structures under near-fault excitations”, Soil dynamics and earthquake Engineering, 28(4), 293-304. 
[7] Wenbin, Q. J. L. (2000). “Static Pushover Analysis-an Analytical Tool for Performance/Displacement-Based Seismic Design”, Building Structure, 6. 
[8] Kilar, V., Petrovcic, S., Koren, D., & Silih, S. (2011). “Seismic analysis of an asymmetric fixed base and base-isolated high-rack steel structure”, Engineering Structures, 33(12), 3471-3482. 
[9] Bhandari, M., et al.(2018). “Assessment of proposed lateral load patterns in pushover analysis for base-isolated frames”, Engineering Structures. 175, 531-548.
[10] Ferraioli, M., & Mandara, A. (2017). “Base isolation for seismic retrofitting of a multiple building structure: design, construction, and assessment”, Mathematical Problems in Engineering. 
[11] Sharbatdar, M. K., Vaez, S. H., Amiri, G. G., & Naderpour, H. (2011). “Seismic response of base-isolated structures with LRB and FPS under near fault ground motions”, Procedia Engineering.14, 3245-3251.
[12] Naeim, F., & Kelly, J. M. (1999). “Design of seismic isolated structures: from theory to practice” John Wiley & Sons.
[13] Bozorgnia, Y., & Bertero, V. V. (2004). “Earthquake engineering: from engineering seismology to performance-based engineering”, CRC press.
[14] FEMA-356 (2000). Pre-Standard and Commentary for the Seismic Rehabilitation of Buildings, Washington, DC.Federal Emergency Management Agency. 
[15] FEMA-273/274 (1997). Guidelines and commentary for the seismic rehabilitation of buildings, Washington, DC.Federal Emergency Management Agency. 
[16] Kilar, V., & Koren, D. (2010). “Simplified inelastic seismic analysis of base?isolated structures using the N2 method. ” Earthquake engineering & structural dynamics, 39(9), 967-989. 
[17] American Society of Civil Engineers (2010). Seismic Design Requirements for Seismically Isolated Structures; Section 17 in ASCE 7-10; Minimum Design Loads for Buildings and Other Structures ASC Reston, VA. 
[18] American Society of Civil Engineers (2014). Seismic Evaluation and Retrofit of Existing Buildings, VA.
[19] FEMA-P695 (2009). Quantification of Building Seismic Performance Factors, Washington, DC.Federal Emergency Management Agency.
Send comment about this article
CAPTCHA Image
Civil Infrastructure Researches
Volume 5, Issue 1 - Serial Number 8
September 2019
Pages 35-49

Files

Share

How to cite

Statistics