Evaluation of Static and Dynamic Behavior of Rigid Columns

Yıl 2018, Cilt: 2 Sayı: 1, 17 - 26, 10.07.2018

Ayse Bengu Sunbul , Hüseyin Mungan Fatih Sünbül

Öz

Construction on soft soils
often requires utilization of ground improvement techniques in order to solve
the problems associated with bearing capacity and stability. These techniques,
in addition to traditional preloading techniques, include various applications
to the ground based on rigid columns. Today, rigid columns can be modelled on a
computer using the finite element method (FEM) prior to the implementation in
the ground and complex ground-structure interaction mechanisms associated with
the applicability of a suitable soil improvement technique can be investigated.
In this study, rigid columns including rammed aggregate piers (RAP), jet
grouting (JG) and bored pile (BP), are tested in realistic finite element
models for both static and dynamic cases. Here, we consider 17 m uniformly distributed
load foundation in FEM modelling. Long term consolidation analysis is performed
in the numerical models to compute stress and deformation variations for static
case. The performance of  rigid columns
in the numeric model is also computed using real earthquake data. In the static
analysis, the settlement values prior to the ground improvement, was around
52.55 cm. After installation, the settlement values has dropped dramatically.
Following the RAP installation, the value has decreased to 26.04 cm. We have
also observed a decrease in other two installations where the settlement values
are 19.11 cm and 7.3 cm for the JG and the BP installations, respectively. Our
dynamic analysis also shows an improvement in the settlement values regardless
of any rigid inclusion ground improvement. It is worthy of note that these
installations considerably enhance building performance in the FEM models

Anahtar Kelimeler

FEM, Ground improvement techniques, Static -dynamic analysis

Kaynakça

• Brinkgreve, F. Plaxis 2D, ISBN-10: 9058095088, Taylor and Francis Group, USA.
• Coulter, S. and Martin, C. D. 2006. Effect of Jet-grouting on Surface Settlements Above the Aeschertunnel, Switzerland, Tunnelling and Underground Space Technology 21 (5), 542–553.
• Durgunoğlu, H. T., Kulaç, F., İkiz, S. and Karadayılar, T. 1992. An Application on Soil Rehabilitation with Stone Columns, 4. National Congress of Soil Mechanics and Basic Engineering, Istanbul Technical University, Turkey.
• Kanmaz, H. 2014. Rijit Kolonların Farklı Zemin Ortamlarındaki Performansları, MSc Thesis, Civil Engineering Department, Graduate School of Natural and Applied Sciences, Istanbul Kültür University, Istanbul, Turkey.
• Karstunen, M. and Leoni, M. 2009. Geotechnics of Soft Soils. ISBN:978-0-415-47591-4, Taylor&Francis Group, London, UK.
• Mitchell, J.K. and Katti, R.K. 1981. Soil Improvement-State-of-the-Art Report, Proceedings of 10th International Conference on Soil Mechanics and Foundation Engineering, California, USA.
• Mungan, H. 2016. Zeminin Kırmataş Kolonları ile İyileştirilmesi, MSc Thesis, Civil Engineering Department, Graduate School of Natural and Applied Sciences, Istanbul Kültür University, Istanbul, Turkey.
• Önalp, A. and Sert S., 2010. Geoteknik Bilgisi 3 Bina Temelleri, Birsen Yayıncılık, ISBN: 978-975-511-465-1, Istanbul, Turkey.
• Parlak, S. 2017. Temel Altı Zemin İyileştirme Yöntemi olan Jet-grout Yöntemi İle İyileştirilen Zeminlerin Sonlu Elemanlar Yöntemi İle Sayısal Analizi, MSc Thesis, Civil Engineering Department, Graduate School of Natural and Applied Sciences, Bulent Ecevit University, Zonguldak, Turkey.
• Peng, F.L., Wang, H.L., Tan, Y., Xu, Z.L., Li, Y.L. 2011. Field Measurements and FEM Simulation of a Tunnel Shaft Constructed by Pneumatic Caisson Method in Shanghai Soft Ground, Journal of Geotechnical and Geoenvironmental Engineering 137 (5), 516–524
• Selçuk, L. 2009. Zemin Sıvılaşmasına Karşı Optimum Taşkolon Tasarımının Sonlu Elemanlar Yöntemiyle Modellenmesi, PhD Thesis, Geological Engineering Department, Graduate School of Natural and Applied Sciences, Ankara University, Ankara, Turkey.
• Toğrol, E. ve Tan, O. 2009. Kazıklı Temeller, Birsen Yayıncılık, ISBN 978-975-511-327-4, Istanbul, Turkey.
• Shen, S., Wang, Z., Horpibulsuk, S. and Kim, Y. 2013. Jet-grouting with a Newly Developed Technology:The Twin-jet Method, Engineering Geology, 152, 87-95.
• Wood, D. 2004. Geotechnical Modelling, ISBN: 9780419237303, Taylor and Francis Group, USA.
• Xanthakos, P., Abramson, L. and Donald, B. 1994. Ground Control and Improvement. ISBN-10:0471552313, New York, USA.