• 한국지반환경공학회 논문집
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• 제13권3호
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• pp.53-58
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• 2012

일반적으로 연약지반인 점성토 지반이나 느슨한 사질토 지반을 개량하기 위하여 모래다짐말뚝(SCP)공법 또는 쇄석다짐말뚝(GCP)공법이 쓰여지고 있다. 하지만 모래다짐공법은 모래의 수급부족과 모래채취로 인한 환경파괴와 같은 문제점이 있으며, 쇄석다짐공법은 쇄석다짐재료의 클로깅으로 인하여 배수재의 투수계수가 저하되는 문제점이 있다. 최근, 모래와 공학적 성질이 유사한 화력발전소 부산물인 저회를 모래의 대체 재료로 활용하기 위한 연구가 이루어지고 있다. 본 연구에서는 저회혼합다짐말뚝에 대한 기초적 연구로써 조립재료 및 치환율에 따른 조립재료 혼합다짐말뚝의 거동특성을 수치해석적으로 규명하였다. 특히, 말뚝중심부로부터 거리에 따른 침하저감비(SRR)를 산정하였다. 연구 결과는 다음과 같았다. 조립재료에 따른 혼합다짐말뚝의 침하저감비 변화값은 유사한 형태를 보였으며 치환율에 따라 복합지반의 강성이 증대하여 침하저감비는 감소하는 형태를 보였다. 특히, 치환율 20~40%의 범위에서는 일반적으로 침하저감비의 증가가 큰 것으로 나타났고, 치환율 40% 이상에서는 증가치가 서서히 감소하는것으로 나타났다. 본 연구에서 적용한 연약지반과 유사한 지반에 혼합다짐말뚝 적용 시 경제성을 고려하였을 때, 30~40%의 치환율이 적절할 것으로 사료된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.705-712
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• 2005

Among soft ground treatment methods with granular soil used in domestic, the sand compaction pile method has been utilized greatly, but, as a result of exhaustion of sand and increase of unit cost, a necessity of an alternative method is suggested. In this study, the static load tests for group crushed-stone compaction piles which were constructed at in-situ site were performed. Pile diameter was 700mm and area of loading plates were changed. The static load tests of single and group piles were performed for area replacement ratio of 20, 30 and 40%. Based on test results, bearing capacity of group crushed-stone compaction pile were estimated. The more both single pile and group pile increase, the more yield bearing capacity tended to increase. Also, the yield bearing capacity of a group pile is about 50% less than the yield bearing capacity of a single pile. If the ground reinforced with the crushed-stone compaction pile is replacement ratio of $20{\sim}40%$, RIYB of both single pile and group pile increases qualitative tendency of linear more than original ground

• 한국농공학회지
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• 제31권1호
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• pp.82-95
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• 1989

This study was carried out for the stability analysis of earth dam by the variation of compaction density. The test samples were taken from five kinds of soil used for banking material and the degree of compaction for this samples were chosen 100, 95, 90, 85, and 80 percent. The stability problems were analysed by the settlement and camber( extra banking) of dam, strength parameter and dam slope, and coefficient of permeability and seapage flow through dam body. The results of the stability analysis of earth dam are as follows. 1. The more the fine particle increases and lower the compaction degree becomes, the lower the preconsolidation load becomes but the compression index becomes higher. 2. Sixty to eighty percent of settlement of dam occurs during the construction period and the settlement ratio after completion of dam is inversly proportional to the degree of compaction. 3. The camber of dam has heigher value in condition that it has more fine particle(N) and heigher dam height(H) with the relation of H= e(aN-bH-e). 4. The cohesion(C) decreases in proportion to compaction degree(D) and fine particle(N) with the relation of C= aD+ bN-c, but the internal friction angle is almost constant regardless of change of degree of compaction. 5. In fine soil, strength parameter from triaxial compression test is smaller than that from direct shear test but, they are almost same in coarse soil regardless of the test method. 6. The safety factor of the dam slope generally decreases in proportion to cohesion and degree of compaction but, in case of coarse soil, it is less related to the degree of compaction and is mainly afected by internal friction angle. 7. Soil permeability(K) decreases by the increases of the degree of compaction and fine particle with relation of K=e(a-bl)-cN) 8. The more compaction thickness is, the less vertical permeability (Kv) is but the more h6rzontal permeability (KH) is, and ratio of Kv versus KH is largest in range from 85 to 90 percent of degree of corn paction. 9. With the compaction more than 85 percent and coefficient of permeability less than ${\alpha}$X 10-$^3$cm/sec, the earth dam is generally safe from the piping action.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.269-276
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• 2000

Granular compaction piled raft systems have been effectively used in soft ground foundation to improve not only settlement but also bearing capacity. In the present study, to examine the behavior characteristics and bulging failure zone on granular compaction piled raft system, carbon rod tests have been performed. The test results are compared with the zone of bulging failure and the effects of pile-pile interaction obtained from the analytical approaches. In addition, parametric studies are peformed with considering pile slenderness ratio, Poisson's ratio and load sharing ratio.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.596-599
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• 2004

The purpose of this study is to investigate properties of porous concrete according to rheological properties of binder and compaction factor. The results of this study, the rheological property of binder is stabilized when a mixing time is over 240 seconds in case of target flow values are $175\%\;and\;200\%$. The void ratio of specimen has a very near value by target void ratio on the whole according as the rheological properties of binder and compaction energy are changed when target flow value is $200\%$, compaction energy is $75kN{\cdot}m/m^2$. The specimen has the excellent compressive strength when compaction energy and target flow value are $100kN{\cdot}m/m^2$ and $200\%$ respectively.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 가을 학술논문 발표대회
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• pp.161-162
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• 2022

The purpose of this study is to determine the viscosity of the polymer-cement composites(PCCs) for crack repair of RC structures and to investigate its compaction. According to the study on the viscosity and compaction property of PCCs for crack repair, the viscosity of PCCs varies greatly depending on the polymer type and polymer cement ratio, and by mixing silica fume into PCCs, appropriate viscosity and excellent flow can be controlled without separation of cement and water. As a result of this study, basic data on the viscosity, fluidity, and compaction properties of PCCs for crack repair of RC structure can be obtained.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1170-1180
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• 2009

Recently this country has carried out the coast reclamation centering on the west and south coast for effective practical use of a country, considering purchase of materials and environmental problem, most reclaiming work is processing to spoil reclamation which is easy to secure the amount of materials. In case of weak ground that is formed by spoil reclamation like this, initial moisture content is high, as slurry state that is rarely revealed ground strength, compressibility and water permeability have been shown nonlinear change by compaction progress. Analysis of weak ground is unreasonable because the existing Terzaghi compaction theory analyzes compaction fixed number to regular invariable number for prediction of compaction state. This study computes the relation with void ratio-effective pressure and void ratio-finite transformation which is the most basic matter to predict finite strain compaction state of the south coast spoil, and analyze the basic feature to predict compaction feature of the south coast spoil reclaimed ground.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.343-348
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• 2005

In this study, construction modulus, void ratio and settlement characteristics of 38 CFRD in domestic and foreign countries was investigated from monitoring data and the effect of field dry density and void ratio to dam body was analyzed. The standard void ratio of CFRD that can be easily used for dam designer and field engineer was proposed from the monitoring data. It was conformed that we can get the degree of compaction needed for reasonable compaction of dam body by calculating the field dry density from inverse operation of the standard void ratio. It was thought that the standard void ratio of CFRD is 0.2 as shape factor is under 4 and is 0.28 as shape factor is over 4.

• 한국지반공학회지:지반
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• 제10권4호
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• pp.5-16
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• 1994

포항지역의 이암풍화토에 관한 공학적특성에 대하여 연구하였다. 토립자의 파쇄는 토립자의 표면적비로 나타냈다. 다짐시 함수비와 다짐에너지의 변화가 입도, CBR, 팽창성, 간극비 그리고 투수성에 미치는 영향에 대하여 연구하였으며, 그 결과는 다음과 같다. 1. 일반적으로 이암풍화토의 비중은 매우 작으며, 최적함수비는 크고 최대건조밀도는 작다. 2. CBR값은 다짐에너지의 증가에 따라 증가하나, D-2다짐(26kg.cm/cm3)이상에서는 오히려 감소하는 경향을 나타냈다. 팽창비는 다짐에너지 20.6kg.cm/cm3에서 최대가 되며 그 이상의 다짐 에너지에서는 감소하는 경향을 나타냈다. 3. 다짐에너지가 작을수록 함수비에 따른 투수성의 변화가 크다. 그리고 최소투수계수와 최적 함수비일때의 투수계수는 차이가 컸으나 다짐에너지가 증가할수록 그 차이는 거의 없었다. 4. 다짐에너지의 증가에 따른 입자의 파쇄는 간극비의 감소 그리고 표면적비의 증가와 그에 따른 투수계수의 감소가 나타났다. 특히 다짐에너지가 작을수록 표면적 비와 투수계수의 변화폭은 컸다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.66-73
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• 2004

Prototype crushed-stone compaction pile(${\Phi}=700mm$) were constructed on specific test site. Static loading tests for crushed-stone compaction piles were performed. Based on the static loading test results, finite element analysis was performed using software PENTAGON 3D. Numerical analysis were done for the area replacement ratio($a_s$) of $20{\sim}70%$ and $a_s$ was varied as a step of 10%. In the single crushed-stone compaction pile, settlement was decreased as $a_s$ was increased. In the group pile, this tendency was similar. In the in-sit test and numerical analysis, as $a_s$ increased, the stress concentration ratio was increased. But $a_s$ in the numerical analysis were more than that of in-situ test, greatly.