Seismic Analysis of Non-Proportionate Eccentric Buildings

Abstract:

A simple procedure is presented for estimating frequencies and the peak values of base resultant forces of eccentric non-proportionate buildings due to earthquake ground motions. Multi-story buildings composed by a number of bents with different stiffness matrices do not belong to the special class of proportionate buildings, which can be analyzed by a simple methodology developed in the past. This paper extends this methodology to all types of medium height buildings and is shown that their maximum response can be derived from the analysis of two single-story modal systems. The accuracy of the proposed method is illustrated in mixed-bent-type example structures and comparisons are made with the accurate results obtained by response spectrum analyses using the SAP2000 computer program.

• Periodical: Advanced Materials Research (Volumes 450-451)
• Pages: 1482-1488
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.450-451.1482
• Online since: January 2012
• Authors: George Georgoussis
• Keywords: Centre of Rigidity, Eccentric Structures, Modal Analysis, Optimum Torsion

References

[1] Kan CL, Chopra AK. Elastic Earthquake Analysis of a Class of Torsionally Coupled Buildings. J. Struct. Div. ASCE, 1977, 103(4), 821-838.

DOI: 10.1061/jsdeag.0004609

[2] Hejal R, Chopra AK. Earthquake Analysis of a Class of Torsionally-Coupled Buildings. Earthquake Engng. Struct. Dyn., 1989, 18: 305-323.

DOI: 10.1002/eqe.4290180302

[3] Athanatopoulou AM, Makarios T and Anastassiadis K. Earthquake Analysis of Isotropic Asymmetric Multistory Buildings. Struct. Design Tall Spec. Build. 2006, 15: 417-443.

DOI: 10.1002/tal.304

[4] Kan CL, Chopra AK. Elastic Earthquake Analysis of Torsionally Coupled Multistorey Buildings Earthquake Engng. Struct. Dyn. 1977, 5: 395-412.

DOI: 10.1002/eqe.4290050406

[5] Georgoussis G.K. Optimum Design of Multi-story Uniform Structures with Simple Eccentricity. Struct. Design Tall Spec. Build. 2008, 17(3): 719-738.

DOI: 10.1002/tal.376

[6] Georgoussis G.K. An Alternative Approach for Assessing Eccentricities in Asymmetric Multistory Structures, 1: Elastic Systems. Struct. Design Tall Spec. Build. 2009, 18(2):181-202.

DOI: 10.1002/tal.401

[7] Georgoussis G.K. Simplified Dynamic Analysis of Eccentric Buildings with a Setback. 1: The Effect of mass Irregularity. Struct. Design Tall Spec. Build. 2009, Early view, TAL567.

DOI: 10.1002/tal.567

[8] Heidebrecht, A.C. and Raina R.K. Frequency Analysis of Thin-walled Shear Walls. J. Engrg. Mech. Div. ASCE, 1971, 97(2), 239-252.

DOI: 10.1061/jmcea3.0001361

[9] Newmark, N.M. and Rosenblueth, E. Fundamentals of Earthquake Engineering. Prentice-Hall, Inc. 1971.

[10] Kan CL, Chopra AK. Effects of Torsional Coupling on Earthquake Forces in Buildings. J. Struct. Div. ASCE, 1977, 103(4), 805-820.

DOI: 10.1061/jsdeag.0004608

[11] Hejal R, Chopra AK. Earthquake Response of Torsionally Coupled, Frame Buildings. J. Struct. Engng ASCE, 1989, 115(4), 834-851.

DOI: 10.1061/(asce)0733-9445(1989)115:4(834)

[12] Hejal R, Chopra AK. Lateral-Torsional Coupling in Earthquake Response of Frame Buildings. J. Struct. Engng ASCE, 1989, 115(4), 852-867.

DOI: 10.1061/(asce)0733-9445(1989)115:4(852)