EFFECT OF IRREGULAR TIME-HISTORY ON THE CYCLIC RESISTANCE OF SAND

Yıl 2019, Cilt: 20 Sayı: 4, 532 - 543, 30.12.2019

Murat Türköz , Kamil Bekir Afacan

https://doi.org/10.18038/estubtda.614690

Öz

The liquefaction behaviors of sandy soils are
generally investigated using stress or strain controlled dynamic tests in the
laboratory.  In terms of ease and
applicability of analysis, uniform loading patterns are usually preferred.
However, irregular wave forms with different amplitudes and frequencies are
generated throughout the soil layers during seismic excitations. In this study,
a comprehensive series of cyclic tests have been performed on clean sand samples.
Conventional uniform loading and ground-motion records scaled to different
cyclic stress ratios were applied to identically prepared specimens. The pore
pressure build-up and accumulated strain effects are investigated regarding the
effect of the loading type and cyclic stress ratio. The outcome of test series
aimed to provide further improvement on dynamic strength approaches for
liquefaction assessment, in order to expand its use in current engineering
practice.

Anahtar Kelimeler

Dynamic Triaxial Test, Irregular Loading, Sand Particles, Excess Pore Water Pressure

Kaynakça

• [1] Finn WDL. State-of-the-art of geotechnical earthquake engineering practice. Soil Dyn Earthquake Eng 20(1):1–15 (2000).
• [2] Kramer SL.: Geotechnical earthquake engineering. Upper Saddle River, NJ: Prentice-Hall(1996).
• [3] Idriss RW, Boulanger W. Semi-empirical procedures for evaluating liquefaction potential during earthquakes. Soil Dyn Earthquake Eng 26: 115–130 (2006).
• [4] Giretti D, Fioravante V. A correlation to evaluate cyclic resistance from CPT applied to a case history. Bulletin of Earthquake Engineering (2016).
• [5] Kwan WS, Sideras S, El Mohtar, C, Kramer S.:Pore pressure generatıon under different transient loadıng hıstories. Tenth U.S. National Conference on Earthquake Engineering Frontiers of Earthquake Engineering July 21-25, Anchorage, Alaska. (2014)
• [6] Seed HB, Idriss IM.: Soil moduli and damping factors for dynamic response analyses. Report no. EERC 70–10, Earthquake Engineering Research Centre, University of California, Berkeley (1970)
• [7] Iwasaki T, Tatsuoka F, Takagi Y. Shear modulus of sands under torsional shear loading. Soils and Foundations 18(1):39–56 (1978).
• [8] Ishibashi I, Zhang X. Unified dynamic shear moduli and damping ratios of sand and clay. Soils and Foundations, 33(1):182–191 (1993).
• [9] Bol E, Önalp A, Arel E, Sert S, and Ozocak A. Liquefaction of silts: the Adapazari criteria. Bulletin of Earthquake Eng. 8: 859 (2010)
• [10] Seed HB, Lee KL. Liquefaction of saturated sands during cyclic loading. J Soil Mech Found Div ASCE, 92(6):105–134 (1996)
• [11] Ishihara K, Yasuda S.: Soil liquefaction under random earthquake loading condition. Proceedings of 5th world conference earthquake engineering. ASCE, Rome, pp 329–338 (1973).
• [12] Kirar B, Maheshwari BK.: Effects of silt content on dynamic properties of Solani sand. Seventh international conference on case histories in geotechnical engineering, Chicago (2013) [13] Kumar SS, Dey A, Krishna AM. Response of saturated cohesionless soil subjected to irregular seismic excitations. Natural Hazards 93: 509-529 (2018).
• [14] Kumar S, Krishna AM, Dey A. Evaluation of dynamic properties of sandy soil at high cyclic strains. Soil Dyn Earthq Eng 99:157–167 (2017).
• [15] ASTM D2487. Standard practice for classification of soils for engineering purposes (unified soil classification system). ASTM International, West Conshohocken (2006)
• [16] ASTM D5311. Test method for load controlled cyclic triaxial strength of soil. Annual book of ASTM standards. ASTM International, West Conshohocken (2011).
• [17] Ladd RS. Specimen preparation and cyclic stability of sands. Journal of the Geotechnical Engineering Division, ASCE 103: 535–547 (1977).
• [18] Yang Z X, Li XS, and Yang J. Quantifying and modelling fabric anisotropy of granular soils. Geotechnique 58(4): 237–248 (2008).
• [19] Sze HY, Yang J. Failure Modes of Sand in Undrained Cyclic Loading:Impact of Sample Preparation. Journal Of Geotechnical And Geoenvironmental Engineering ASCE, 140:152-169 (2014).