초록

벤더엘리먼트 시험은 시험시편의 전단파속도를 직접 측정함으로써 최대전단탄성계수를 평가하기 위한 시험법으로, 다양한 실내시험장비에 간단히 부착되어 다양한 시험조건에서 시편의 최대전단탄성계수를 평가할 수 있는 유용한 시험기법으로 현재 널리 이용되고 있는 추세다. 본 연구에서는 포화가 가능하도록 개조된 Stokoe식 공진주/비틂전단 시험장비에 벤더엘리먼트 시험장비를 부착하여 동일한 시험시편에 대하여 다양한 조건에서 벤더엘리먼트 시험, 공진주 시험, 비틂전단 시험의 세 가지 시험을 동시에 수행함으로써 각 시험법에 의하여 평가되는 최대전단탄성계수를 비교하였으며, 벤더엘리먼트 시험기법을 검증해보고자 하였다. 또한 포화조건에서 Biot의 이론을 적용하여 각 시험기법의 하중주파수를 고려함으로써 보다 타당한 비교를 수행할 수 있었다.

Abstract

The bender element method is an experimental technique to determine very small strain ($<10^{-3}\%$), elastic shear modulus of a soil, $G_{max}$ by measuring the velocity of shear wave propagation through a sample. Bender elements have been applied as versatile transducers to measure small strain modulus of wet or dry soils in various laboratory apparatus. In this paper, bender element (BE), resonant column (RC) and torsional shear (TS) tests were performed on Toyoura sand at various testing conditions using the modified Stokoe type RC/TS testing equipment capable of performing BE test. Based on the results, applicabilities of the testing method using bender element were evaluated by comparing the values of $G_{max}$ obtained from RC/TS and BE testing methods. For more dependable evaluation, the loading frequency of each testing method was considered for the results obtained for samples in saturated condition by adapting Biot's theory.

주제어

#Bender element testing   #Resonant-column testing   #Shear wave   #Small strain stiffness   #Torsional shear testing  

저자의 다른 논문

참고문헌 (10)

1. 김동수, 추연욱 (2004), '간극수압증가와 동적변형특성 변회에근거한 사질토 지반의 반복한계 전단변형률', 대한토목학회논문집, Vol.24, No.3C, pp.193-203 
2. Arulnathan, R., Boulanger, R. W., and Riemer (1998), M. F., 'Analysis of Bender Element Tests', Geotechnical Testing Journal, GTJODJ, Vol.21, No.2, pp.120-131 
3. Biot. M. (1956b), 'Theory of propagation of elastic waves in fluid-saturated porous solid. II. High frequency range', Journal of the Acoustical Society of America, 28, 179-191 
4. Viggiani, G. and Atkinson, J. H. (1995), 'Interpretation of Bender Element Tests', Geotechnique, Vol.45, No.1, pp.149-154 
5. Dyvik, R. and Madshus, C. (1985), 'Laboratory Measurements of Gmax using Bender Elements', Engrs Convention, Detroit. New York: Ameriean Society of Civil Engineers. pp.186-196 
6. Biot. M. (1956a), 'Theory of propagation of elastic waves in fluid-saturated porous solid. I. Low frequeney range', Journal of the Acoustical Society of America, 28, 168-178 
7. Stoll, R. D. (1979), 'Experimental Studies of Attenuation in Sediments', Acoustical Society of America, Vol.66, pp.1152-1160 
8. Berryman, J. G. (1981), 'Elastic Wave Propagation in Fluid-saturated Porous Media', J. Acoust. Soc. Am., Vol.69, pp.416-424 
9. Santamarina, J. C., Klein, K. A., and Fam, M. A. (2001), Soils and Waves, John Wiley & Sons, LTD, pp.238-282 
10. Kamon, M., Endo, K., Kawabata, J., Inui, T., and Katsumi, T. (2004), 'Two-dimensional DNAPL migration affected by groundwater flow in unconfined aquifer', Journal of Hazardous Materials, Vol.110, No.1, pp.1-12 

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1. Lee, Sei-Hyun ; Choo, Yun-Wook ; Youn, Jun-Ung ; Kim, Dong-Soo 2007. "Determinations of P, S-Wave Velocities and Pore Water Pressure Buildup with B-value for Nearly Saturated Sands" 韓國地盤工學會論文集 = Journal of the Korean geotechnical society, 23(2): 71~83  원문보기 상세보기
2. Jang, In-Sung ; Kwon, O-Soon ; Kim, Byoung-Il ; Lee, Seung-Hyun 2008. "Parametric Studies for Measurements of Dynamic Properties of Soils Using Inhole type CPTu" 한국해안·해양공학회논문집 = Journal of Korean Society of Coastal and Ocean Engineers, 20(6): 523~531  원문보기 상세보기
3. Lee, Sei-Hyun ; Seo, Won-Seok ; Choo, Yun-Wook ; Kim, Dong-Soo 2008. "Development of VPPE-BE Testing System to Evaluate Modulus under Post-Compaction Variation in Matric Suction for Unsaturated Compacted Soils" 韓國地盤工學會論文集 = Journal of the Korean geotechnical society, 24(5): 117~127  원문보기 상세보기
4. Hong, Sung-Jin ; Yoon, Hyung-Ko ; Lee, Jong-Sub ; Lee, Woo-Jin 2009. "The Prediction Method of the Small Strain Shear Modulus for Busan Clay Using CPT and DMT" 韓國地盤工學會論文集 = Journal of the Korean geotechnical society, 25(6): 5~16  원문보기 상세보기
5. Cho, Wan-Jei 2010. "Influence of Sampling and Preparation Method on Stress-Strain Behavior of Weathered Granite Soils" 한국안전학회지 = Journal of the Korean Society of Safety, 25(2): 55~64  원문보기 상세보기