Betonarme Binalarda Zemin-Yapı Etkileşiminin Sismik Tasarım Parametrelerine Etkileri

Year 2022, Volume: 9 Issue: 2, 507 - 521, 31.05.2022

Mehmet Özgür , Kanat Burak Bozdoğan

https://doi.org/10.31202/ecjse.966259

Cited By: 1

Abstract

Yapıların deprem davranışı birbirlerine bağlı olan zemin, temel ve yapı alt-sistemleri arasındaki etkileşim nedeniyle değişebilmektedir. Genellikle temel, yapının bir bölümü olarak kabul edilir ve bu etkileşim zemin-yapı etkileşimi (ZYE) olarak anılır. ZYE, rijit (ankastre) temel yaklaşımından farklı olarak esnek zemin-temel sistemi, temel sönümü ve yapıya iletilen yer hareketinin filtrelenmesi gibi faktörleri kapsar. Esnek zemin-temel sistemi ve temel sönümüne bağlı olarak sırasıyla ortak sistem periyodunun uzaması ve sönüm oranının artması eylemsizlik etkileşiminin sonuçlarıdır. Öte yandan, serbest saha hareketinin temel girdi hareketinden farklılaşması kinematik etkileşim olarak değerlendirilir. Bu çalışmanın amacı esnek zemin-temel sistemi nedeniyle bina periyodunda gerçekleşen uzamayı farklı yapı sistemlerine sahip binalar ve yerel zemin sınıflarında ortaya koymaktır. Ayrıca periyoda bağlı olan spektral ivme ve deplasman, taban kesme kuvveti ve tepe deplasmanı gibi bazı sismik tasarım parametrelerinin değişimi de gösterilmiştir. ZYE ile elde edilen sismik parametreler, ZYE etkilerinin zayıf zeminler üzerinde yer alan rijit binalar için daha belirgin olduğunu ortaya koymaktadır.

Keywords

Zemin-yapı etkileşimi, zemin sınıfı, periyot uzaması

Effects of Soil-Structure Interaction on Seismic Design Parameters of Reinforced Concrete Buildings

Abstract

The earthquake response of structures can alter due to the interactions between the linked subsystems; soil, foundation and structure. Generally, the foundation is assumed as a part of the structure and the related interaction is then called as soil-structure interaction (SSI). In contrast to approach of rigid (fixed) foundation, SSI comprises factors such as flexible soil-foundation system, foundation damping and filtering the ground motion transmitted to the structure. The period elongation and the increase in the damping ratio of the overall system due to the flexible soil-foundation system and the foundation damping, respectively, are referred as the inertial interaction effects. On the other hand, the difference between the free-field ground motion and the foundation input motion is stated as the kinematic interaction effect. The aim of this study is to determine the period elongation due to the flexible soil-foundation system for buildings with different structural systems resting on soils with different local soil classes. Seismic design parameters related with the period such as spectral acceleration and displacement, base shear force and top displacement are also determined. Seismic parameters obtained with SSI approach point out that the effects of SSI becomes more significant for rigid buildings on weak soils.

Keywords

Soil-structure interaction, soil class, period elongation

References

• Steward, J. P., Seed, R. B., Fenves, G. L., “Emprical Evaluation of Inertial Soil-Structure Interaction Effects”, Pacific Earthquake Engineering Research Center, PEER 1998/07, California, 1998.
• Chopra, A. K., Gutierrez, J. A., “Earthquake response analysis of multistory buildings including foundation interaction” Earthquake Engineering Structural Dynamics, 1974, (3): 65–77.
• Bielak, J., “Modal analysis for building-soil interaction”, Journal of the Engineering Mechanics Division ASCE, 1976, 102(5): 771–786.
• Iguchi, M., “Dynamic interaction of soil–structure with elastic rectangular foundation”, 5. Japanese Earthquake Engineering Symposium, Tokyo, Japan, 457–464, 1978.
• TBDY18, “Türkiye Bina Deprem Yönetmeliği”, 2018.
• FEMA P–2091, “A Practical Guide to Soil-Structure Interaction”, 2020.
• Steward, J. P., Seed, R. B., Fenves, G. L., “Seismic soil-structure interaction in buildings. II: Empirical Findings”, Journal of Geotechnical and Geoenvironmental Engineering, 1999, 125(1): 38–48.
• Dutta, S. C., Bhattacharya, K., Roy, R., “Response of low-rise buildings under seismic ground excitation incorporating soil–structure interaction”, Soil Dynamics and Earthquake Engineering, 2004, 24(12), 893–914.
• Behnamfar, F., Banizadeh, M., “Effects of soil–structure interaction on distribution of seismic vulnerability in RC structures”, Soil Dynamics and Earthquake Engineering, 2016, (80): 73–86.
• ASCE/SEI 7–16, “Minimum Design Loads and Associated Criteria for Buildings and Other Structures”, 2016.
• Nguyen, H. D., Shin, M., “Effects of soil–structure interaction on seismic performance of a low-rise R/C moment frame considering material uncertainties”, Journal of Building Engineering, 2021, (44): 102713.
• Asadi-Ghoozhdi, H., Attarnejad, R., “A Winkler-based model for inelastic response of soil–structure systems with embedded foundation considering kinematic and inertial interaction effects”, Structures, 2020, (28): 589–603.
• Kara, D., Bozdoğan, K. B., Keskin, E., “Çerçeve sistemlerin yapı zemin etkileşimli serbest titreşim analizi”, Politeknik Dergisi, 2020, 23(4): 1347–1355.
• Miranda, E., Reyes, C. J., “Approximate lateral drift demands in multistory buildings with nonuniform stiffness”, Journal of Structural Engineering, 2002, 128(7): 840–849.
• CSI, “SAP2000 Integrated Software for Structural Analysis and Design”, Computers and Structures Inc., Berkeley, California.
• NIST GCR 12-917-21, “Soil-Structure Interaction for Building Structures”, 2012.
• Pais, A., Kausel, E., “Approximate formulas for dynamic stiffnesses of rigid foundations”, Soil Dynamics and Earthquake Engineering, 1988, 7(4): 213–227.