저소성 실트의 비배수 전단거동 특성과 예측

국문 초록 (Abstract)

본 연구는 저소성 실트의 비배수 전단거동특성을 파악하기 위해서 낙동강 중류에서 채취한 저소성 실트를 이용하여 비배수 삼축압축시험을 수행하였다. 시험 결과 축차응력은 항복응력에 도달한 후 사질토의 거동인 경화현상이 나타났으며, 간극수압은 최대값 이후 감소하여 한계상태에 도달하였다. 유효응력경로에서는 압밀응력이나 과압밀비에 상관없이 사질토와 같이 한계상태선(CSL)과 상태전이선(PTL)이 존재하였다. 저소성 실트 거동에 대해 Modified Cam-Clay(MCC) 모델과 동적인공신경망 모델인 Jordan과 Elman-Jordan 모델을 적용하여 예측을 실시하였다. 예측결과, MCC model은 저소성 실트의 전반적인 거동을 예측할 수 없었으나, Jordan과 Elman-Jordan 모델은 모두 저소성 실트의 거동을 비교적 잘 예측하였다.

다국어 초록 (Multilingual Abstract)

In this study, undrained triaxial (CU) tests were performed on low-plastic silt of Nakdong River in order to investigate the undrained shear behavior of low-plastic silt. In experimental results, the deviator stress showed the hardening behavior after reaching its yield stress like the tendency of common sand, and the pore water pressure was gradually decreased to critical state after the maximum value. In the effective stress paths, regardless of consolidation stress or overconsolidation ratios, both a critical state line (CSL) and a phase transformation line (PTL) exist in the effective stress path that is similar to the case of sand. The behavior of low-plastic silt was predicted by the Modified Cam-Clay (MCC) model, the Jordan and the Elman-jordan model that is artificial neural network model. According to predicted results, the overall undrained shear behavior of low-plastic silt could not be predicted with the MCC model, but the Jordan and Elman-Jordan model showed well-matched experiment results.

참고문헌 (Reference)

1 정상섬, "체적변형 경향에 따른 실트의 거동" 13 (13): 255-260, 1993a

2 정상섬, "사질토 및 점성토와 비교한 순수 실트의 응력-변형률 거동" 9 (9): 27-35, 1993b

3 Konrad, J. M., "Undrained cyclic behavior of Beaufort Sea silt" 830-837, 1985

4 Schultze, E., "The shear strength of silt" 350-353, 1965

5 Atkinson. J. H., "The mechanics of soils" McGraw-Hill 210-233, 1978

6 Fleming, L. N., "Stress-Deformation characteristics of Alaskan silt" 116 (116): 377-393, 1990

7 Ladd, C. C., "Strength-deformation properties of Arctic Silt" 820-829, 1985

8 Lambe, T. W., "Soil mechanics. SI version" MIT/Wiley & Sons 423-494, 1969

9 Borgesson, L., "Shear strength of inorganic silty soils" 567-572, 1982

10 Penman, A. D. M., "Shear Characteristics of a Saturated Silt" 3 (3): 312-328, 1985

11 Roscoe, K. H., "On the generalized stress-strain behavior of ‘wet’ clay" Cambridge Univ. press 535-609, 1968

12 Garson, G. D., "Interpreting neural-network connection weight" 6 (6): 47-51, 1991

13 Wang, J. L., "Geotechnical properties of Alaskan OCS marine silts" 415-420, 1982

14 김영수, "Characteristics of Shear Behavior of Remolded Nak-dong River Sandy Silt" 한국지반공학회 23 (23): 41-50, 2007