• 한국해안해양공학회지
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• 제13권4호
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• pp.282-289
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• 2001

본 연구는 경남해안지역 연약점토의 토질특성과 압축지수와의 관계를 알아보기 위해 김해지역 82개소, 진해지역 18개소, 거제지역 27개소의 불교란 상태의 시료를 채취하여 물성실험 및 역학실험을 실시하였다. 그 결과, 경남해안지역 연약점토의 압축지수는 Terzaghi & Peck이 제안한 경험식을 적용할 수 없음을 알 수 있었다. 경남 해안지역 연약점토의 압축지수는 자연함수비, 액성한계, 초기간극비와 상관성이 있었으며, 이들 중 압축지수는 초 기간극비와 상관성이 가장 컸다. (1) 경남해안지역 연약점토의 압축지수는 $C_c=0.74(e_o-0.7$로 나타낼 수 있다. (2) 경남해안지역 연약점토의 압축지수와 팽창지수와의 관계는 $C_s=(1/8-1/15)C_c$이다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1081-1089
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• 2008

Highly plastic clays in their normally consolidated state are not linear but are concave upwards. Thus their compression index deceases with the increase in consolidation pressure. Likeness the e - log ${\sigma}\;_{\upsilon}\;'$ curves of the silts are not linear but are convex upwards. In this paper, conducted consolidation test with four undisturbed field soil and found that their e - log ${\sigma}\;_{\upsilon}\;'$ plots are not linear. And analyzed difference of settlement between computed value with compression index($C_c$) and computed value with improved compression index($\mathbb{C}$).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 가을 학술발표회 논문집
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• pp.537-544
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• 2002

Deformations of clays continue beyond the end of primary consolidation: this is secondary consolidation. Mesri(1973) have shown that C $\_$a/' is related to the natural water content W$\_$n/. For clays, C $\_$a/' is approximately equal to 0.01 W $\_$n/. And the ratio C $\_$ae// C $\_$c/ is approximately equal to 0.04. In this study, coefficient of secondary compression was analyzed by the consolidation tests datas in the 3 sites. In conclusion, coefficient of secondary compression was similar to Mesri's suggestions.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.376-381
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• 1998

The large scaled field test by prefabricated vertical drains was performed to evaluate the superiority of vertical discharge capacity for drain materials through compare and analyze the time-settlement behavior with drain spacing and the compression index and consolidation coefficient obtained by laboratory experiments and field monitoring system 1. The relation of measurement settlement( $S_{m}$) versus design settlement( $S_{t}$) and measurement consolidation ratio( $U_{m}$) versus design consolidation ratio( $U_{t}$) were shown $S_{m}$=(1.0~l.1) $S_{t}$, $U_{m}$=(1.13~l.17) $U_{t}$, at 1.0m drain spacing and $S_{m}$=(0.7~0.8) $S_{t}$, $U_{m}$=(0.92~0.99) $U_{t}$ at 1.5m drain spacing, respectively. 2. The relation of field compression index( $C_{cfield}$) and virgin compression index( $V_{cclab}$) was shown $C_{cfield}$=(1.0~1.2) $V_{cclab}$, But it was nearly same value when considered the error with determination method of virgin compression index and prediction method of total settlement. 3. field consolidation coefficient was larger than laboratory consolidation coefficient, and the consolidation coefficient ratio( $C_{h}$/ $C_{v}$) were $C_{h}$=(2.4 ~ 3.0) $C_{v}$. $C_{h}$=(3.5 ~ 4.3) $C_{v}$ at 1.0m and 1.5m drain spacing and increased with increasing of drain spacingngasing of drain spacingng spacingng

• 한국지반공학회논문집
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• 제31권4호
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• pp.13-18
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• 2015

하중이 가해지면 수십 cm에서 수 m까지 침하가 발생하는 준설매립지반의 압축특성 파악은 매우 중요하다고 할 수 있으나, 고 합수비와 낮은 전단강도로 인해 불교란 시료채취가 불가능하고 압밀시험 또한 불가능한 실정이다. 이러한 문제를 해결하기 위해 본 논문에서는 N. Keith Tovey의 omega point와 점토의 물리적 특성변화에 대한 기본적인 가정을 이용하여 원지반과 준설매립점토 사이에는 $C_{c(d)}=F(e_d,C_c)$ 관계를 가진다는 것을 수학적으로 증명하였으며, 제안식의 신뢰성을 검증하기 위해 준설매립을 통해 지반이 조성된 국내 1개 현장에서 수행된 계측결과에 대한 분석결과, 매우 양호한 상관관계를 보이는 것으로 나타났다.

• Geomechanics and Engineering
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• 제37권4호
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• pp.371-382
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• 2024

Measurement or prediction of compression index (C_c) of soils is essential for assessment of total and differential settlement of structures. It is a well-known fact that this parameter is controlled by several index identifiers of soil including initial void ratio, Atterberg limits, overconsolidation ratio, specific gravity, etc. Many studies in the past proposed relationships for prediction of C_c based on different index properties. Therefore, this study aims to present a comparison of previously proposed equations for estimation of C_c. Data from literature was compiled, and a total of 90 and 623 test results on remolded and undisturbed specimens were used to question the validity of previously proposed equations. Nevertheless, the modeling ability of 7 and 12 equations for estimation of C_c of remolded and undisturbed soils were questioned by use of compiled data. Moreover, new empirical relationships based on initial void ratio and toughness limit for prediction of C_c was proposed by use of nonlinear multivariable regression and evolutionary based regression analyses. The results are promising-the performances of models established are quite acceptable, which are verified by statistical analyses.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.171-174
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• 2003

The relationships between compression index, $C_c$, which is the slope of the e-log p curve from consolidation test, and other physical properties of remolded and undisturbed clays were examined. After examined, it is clarified that the $C_c$-initial porosity, $n_0$, relationship is better correlation than the $C_c$-other factors relationship, and a new $C_c$ equations using $n_0$ for remolded and undisturbed clays were suggested.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.317-320
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• 2002

The compression index, $C'_c$ and the swelling index, $C'_s$ which are obtained from the e-log p curve of the consolidation test, are used to calculate the consolidation settlement. In this research, $C'_c$ and the two new methods of $C'_s$ i.e. $C'_{s1}$, $C'_{sm}$ for remolded clays were examined with the $({\omega}_0-{\omega}_p)$ and $(e_0-e_p)$ which are satisfied with the condition and the type of soil. Moreover, the relationships of $C'_{s1}$, and $C'_{sm}$ versus $C'_c$ were obtained.

• Geomechanics and Engineering
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• 제16권2호
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• pp.125-140
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• 2018

Tianjin, which is located on the west shore of the Bohai Sea, is part of China's Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early $21^{st}$ century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, $C_c$, coefficient of consolidation, $C_v$, and hydraulic conductivity change index, $C_{kv}$, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, $C_a$, is also investigated, and the results show that the ratio of $C_a/C_c$ for Tianjin marine clay can be used to calculate $C_a$ in secondary consolidation settlement predictions.

• 한국관개배수논문집
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• 제5권1호
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• pp.75-82
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• 1998

A multivariate regression analysis for compression index and com- pressibility ratio of clayey soils in regard to some soil indices, i.e natural water content, Atterberg limits, and in-situ void ratio, was presented to estimate the primary consolidation s