• Journal of the Korean Geotechnical Society
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• v.16 no.3
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• pp.163-172
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• 2000

최종침하 예측기법들은 분석상 간단명료하고 경제적인 기법이라 현장에서 널리 이용되고 있지만, 현장계측상의 문제들이 다분히 있는 실측치에 크게 의존함으로써 설계단계에서 침하량예측에 분석가의 주관적 판단이 큰 변수로 작용할 수 있으므로 객관성이 결여되는 결점을 안고 있다. 그 중 쌍곡선법(Hypervolic Method)이 가장 널리 쓰이고 있지만, 현장 계측치에 따라 가정 기본식의 선형성이 다소 뚜렷하지 않아 분석가에 따라 해석결과가 다르게 나타날 수 있으므로, 기술 적용상의 어려움과 경제적 비용을 더욱 가중시키는 결과를 초래할 수 있다. 따라서, 본 연구에서는 현장 계측자료 분석에 있어서 대표적으로 널리 적용되고 있는 쌍곡선법의 기본 가정식의 선형성 문제에 주안점을 두어 기본 가정식의 선형성을 확보하고, 그 선형구간을 확장한 새로운 침하예측기법을 제안하였다. 성토완료 직후의 현장 자료를 배수재가 설치된 지역과 배수재가 설치되지 않은 지역으로 구분하여 최종 1차 압밀침하량, 수직압밀계수 등을 기존예측기법 및 현장계측자료와 비교 검토하여 제안된 침하예측기법의 적용성을 검증하였다.

• Geotechnical Engineering
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• v.13 no.6
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• pp.5-12
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• 1997

Predictions of settlements under preloading for the improvement of soft soil is a very important element of construction management. Due to the non uniformity, difficulty of estimating resonable soil properties, predictions of settlements and settlement velocities at the design stage seldom agree with the actual future settlements. To overcome this problem, the prediction methods based on the settlement observation of initial preloading stage such as hyperbolic method and Asaoka method have been employed frequently. However the estimating method for the reliability of these predictions at the time of prediction has not been suggested. In this study, comparisons of predicted settlements by hyperbolic met hed and observed settlements are explored through case studies. And a stratagem of estimating reliability of settlement predictions by hyperbolic method is suggested as the result of investigation on the relationship between the initial observed time and error of settlement prediction by hyperbolic method.

• Journal of Industrial Technology
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• v.28 no.A
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• pp.11-17
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• 2008

Applicability of hyperbolic settlement prediction method to consolidation settlement in the dredged and reclaimed ground was assessed by analyzing results of centrifuge tests modelling self-weight consolidation of soft marine clay. From literature review about self-weight consolidation of soft marine clays located in southern coast in Korea, constitutive relationships of void ratio - effective stress - permeability and typical self-weight consolidation curves with time were obtained by analyzing centrifuge model experiments. For the condition of surcharge loading, exact solution of consolidation settlement curve obtained by using Terzaghi's consolidation theory was compared with results predicted by the hyperbolic method. It was found to have its own inherent error to predict final consolidation settlement. From results of analyzing thc self-weight consolidation with time by using this method, it predicted relatively well in error range of 0.04~18% for the case of showing the linearity in the relationship between T vs T/S in the stage of consolidation degree of 60~90 %. However, it overestimated the final settlement with large errors if those relation curves were nonlinear.

• Journal of the Korean Geotechnical Society
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• v.21 no.3
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• pp.141-148
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• 2005

The settlement measured in the field shows a considerable difference from the predicted settlement due to various factors such as nonhomogeneous soft layers, sampling disturbance, erroneous selection of soil parameters and deficiency of consolidation theories among others. Therefore, analysis of actual settlement behavior based on the instrumentation and measurement data during consolidation period is a very useful procedure in evaluating the rates of consolidation settlement. This paper introduces a new practical method of analyzing consolidation settlement behavior, which is generalized and formulated from the existing analysis methods such as Hyperbolic method, Hoshino method and $\sqr{s}$ method. Through case studies, it is shown that the proposed method is a superior technique in reflecting the measured settlement behavior.