• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1378-1382
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• 2009

This study is conducted to investigate the possibility of the utilization of the mixed soil formed by mixing stone sludge, bentonite, and residual soil as a soil sealant sustaining both stability and capacity in the barrier system. And the mixed soil formed by mixing stone sludge, river sand is conducted to investigate the possibility of recycle. A series of tests were performed on the mixed soil(stone sludge, bentonite, Cement and residual soil) to evaluate basic properties such as compaction, compressive strength, permeability of these materials. and the stone sludge-river sand mixed soil were performed the discharge capacity tests.

• Computers and Concrete
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• 제12권6호
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• pp.785-802
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• 2013

Ready-mixed soil material, known as a kind of controlled low-strength material, is a new way of soil cement combination. It can be used as backfill materials. In this paper, artificial neural network and nonlinear regression approach were applied to predict the compressive strength of ready-mixed soil material containing Portland cement, slag, sand, and soil in mixture. The data used for analyzing were obtained from our testing program. In the experiment, we carried out a mix design with three proportions of sand to soil (e.g., 6:4, 5:5, and 4:6). In addition, blast furnace slag partially replaced cement to improve workability, whereas the water-to-binder ratio was fixed. Testing was conducted on samples to estimate its engineering properties as per ASTM such as flowability, strength, and pulse velocity. Based on testing data, the empirical pulse velocity-strength correlation was established by regression method. Next, three topologies of neural network were developed to predict the strength, namely ANN-I, ANN-II, and ANN-III. The first two models are back-propagation feed-forward networks, and the other one is radial basis neural network. The results show that the compressive strength of ready-mixed soil material can be well-predicted from neural networks. Among all currently proposed neural network models, the ANN-I gives the best prediction because it is closest to the actual strength. Moreover, considering combination of pulse velocity and other factors, viz. curing time, and material contents in mixture, the proposed neural networks offer better evaluation than interpolated from pulse velocity only.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.137-145
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• 2004

Limestone zone in korea have been distributed to diagonal line so that it is wide from the Gangwondo to the Jeonlanamdo. The limestone cavity and fractured zone were formed by chemical weathering. Limestone cavity and fractured zone was reinforced with cemented milk(w/c=60%)by high pressure jet grouting by tripple -pipe to establish bridge foundation on the ground condition like limestone cavity. To analyze property of limestone and solid of cement milk(w/c=65%), mixed solid of cement, core NX size in the limestone cavity and fractured zone and compressive strength. Seismic tomograpy exploration was pcrforn1cd to analyze deformation modulus of limestone. The analysis suggests that deformation modulus of limestone has effect on uniaxial compressive strength, seismic velocity, seismic elasticity modulus. Average static elasticity modulus of limestone is $5.08{\times}10^5kgf/cm^2$, cement and coal mixed solid is $0.25{\times}10^5kgf/cm^2$, $0.095{\times}10^5kgf/cm^2$. Average seismic velocity of limestone is 5.240m/sec, cement and coal mixed solid is 2,211.3m/sec, 1,447.5m/sec. Average uniaxial compressive strength of limestone was $1,221.3kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $125.22kgf/cm^2$, $35kgf/cm^2$ each other. Average friction angle of limestone was $49.14^{\circ}$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $38.39^{\circ}, 25.83^{\circ}$ each other. Average cohesion of limestone was $137.7kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $23.5kgf/cm^2$, $15.5kgf/cm^2$ each other. Average deformation modulus of limestone was $2.84{\times}10^5kgf/cm^2$ and limestone specimen mixed with cement milk and solid of cement milk mixed with coal were $0.4{\times}10^5kgf/cm^2, 0.12{\times}10^5kgf/cm^2$ each other. It was analyzed that the elasticity and uniaxial compressive strength, seismic velocity of solid of cement milk mixed limestone pieces and coal had an highly interrelation regardless of existence of limestones pieces and coal but it had shown that limestones had an lower interrelation. In case of field seismic velocity and deformation of limestone, SIC solid of cement milk mixed with coal and limestone pieces had an highly interrelation.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권1호
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• pp.35-42
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• 2019

In installation of groundwater wells, grouting materials are injected between the groundwater borehole and the inner casing in order to prevent infiltration of contaminated groundwater from the top soil layers into wells. The injection device of grouting materials is commonly composed of an inlet head device with an expansion packer, a cylinder capable of storing the grouting materials, and an air cylinder. In this work, two types of common grouting materials, silicon and cement materials, were tested for their performances as grouting media. For silicon. silicon was mixed with clay or calcite, and tested for their tensile strength and underwater reactivity. Both silicon-clay and silicon-calcite mixtures had adequate flow and adhesiveness. For cement material, general cement, ultra-rapid harding cement, and natural cement were respectively mixed with three different soil types including coarse-grained granite, fine-grained granite, and gneiss, and direct shearing tests were conducted after hardening. Under grouting depth condition of 30 m, the minimum adhesive strength was greater for weathered gneiss than non-weathered gneiss with its maximum values obtained from the mixtures of ultra rapid-harding cement.

• 한국농공학회지
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• 제44권6호
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• pp.115-123
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• 2002

This study was performed to provide basic data for development and construction of reinforced soil wall that mixed with reinforcements such as calcium carbonate, monofilament fiber. In order to determine proper moisture content and mixing ratio by weight of reinforcement, Poisson's ratio and compressive strength tests for sandy soil had been conducted. Model tests for long-term behavior of reinforced soil wall were carried out to investigate the effect of reinforcement during loads and under static loads. The results of creep and model tests for sandy soil compared with clayey soil. Reinforced sandy soil mixed with calcium carbonate and cement showed brittle rupture by shear but that of mixed with monofilament fiber showed ductile rupture due to the tension force of fiber. It was shown that when age increased, creep strain of reinforced soil under sustained load approached constant values.

• 한국지반환경공학회 논문집
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• 제9권7호
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• pp.37-43
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• 2008

알루미늄 제조 시 발생하는 산업부산물인 Red mud가 첨가된 흙-시멘트 포장 재료를 개발하기 위하여 일축압축강도시험을 수행하였으며 Red mud 함유율, 시멘트 함유율, Fly ash 대체 비율 및 모래의 대체 비율이 일축압축강도에 미치는 영향을 검토하기 위하여 양생기간 7일, 14일 및 21일에 대한 공시체를 제작하였다. 시험결과, Red mud와 Fly ash 함유량이 감소할수록 시멘트 함유량이 증가할수록 일축압축강도는 증가하였고, 화강풍화잔류토를 사용할 경우 모래의 대체 비율에 따른 일축압축강도에 미치는 영향은 없는 것으로 나타났다.

• 한국농공학회논문집
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• 제54권6호
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• pp.159-167
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• 2012

In the present study, an investigation has been made on the application of cement-bentonite soil mixtures as the countermeasure against leachate produced by buried animal carcasses. For this purpose, the strength characteristics of the cement-bentonite soil mixtures mixed with geotextile and metakaolin. After the mixtures with different contents of the cement (0 %, 10 %), bentonite (0 %, 5 %, 10 %, 15 %, 20 %), and weathered soil (100 %, 95 %, 90 %, 85 %, 80 %) were prepared, metakaolin and geotextile were added with different contents (metakaolin : 0 %, 5 %, 10 %, 15 %, 20 % of the cement weight; geotextile : 0 %, 0.5 %, 1 %, 1.5 %, 2 %). Experimental results suggested that the early strength of the mixture increases due to the pore filling, the hydration acceleration, and the pozzolan reaction when metakaolin of 5~10 % of the cement weight was added. In addition, the compressive strength increase when 0.5~1 % geotextile contents were added, and the above these contents, the rate of strength increase was gradually decreased because of the fibrous tangles.

• 한국지반환경공학회 논문집
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• 제13권6호
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• pp.19-26
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• 2012

본 연구에서는 산업부산물 중 고로슬래그를 기본 재료로 바이패스 더스트(Bypass dust), 플라이애쉬와 인산석고를 자극제로 활용하고 원료들 간의 화학적 상호작용을 이용하여 개발된 지반 고화제의 개량효과를 판단하기 위하여 화강풍화토 및 준설된 해성점토에 다양한 혼합비로 혼합하여 기본 물성실험과 일축압축실험을 실시하였다. 화강풍화토와 혼합하여 실험한 결과, 인산석고를 자극제로 활용한 B-2고화제가 바이패스 더스트를 자극제로 활용한 B-1고화제에 비해 우수한 강도를 발현하였다. 화강풍화토에 5~7%의 무게비로 혼합된 B-1 및 B-2고화제는 일반 포트랜트 시멘트(OPC)에 비해 44%~60%의 강도를 발현시키나 원료가 산업부산물이므로 특별히 높은 강도를 요구하지 않는 지반구조물에 사용된다면 시멘트뿐 아니라 현재 국내에서 판매되는 고화제에 비해 경제적인 것으로 판단된다. 또한 해성준설토에 5~14%로 혼합하여 실험한 결과, 양생일 및 혼합비 증가에 따라 혼합토의 강도는 증가하며 B-1 고화제의 경우 양생일에 대해 선형적으로 증가하여 14% 혼합비에서 28일 양생일의 일축압축강도가 OPC혼합토에 비해 40%의 강도를 보이나 B-2는 양생일에 대해 비선형적으로 증가하여 OPC 혼합토 대비 133%로 매우 큰 강도를 발현하였다. 한편 B-1혼합토와 B-2혼합토의 변형계수는 $E_{50}=(20{\sim}47)_{qu,28}$ 범위인 것으로 나타나 OPC 혼합 준설토의 하한계 값에 가까운 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.537-540
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• 2004

Recently, for industrial development period, concrete structures in domestics have been increased. They were deteriorated by attack of carbonation, freeze-thaw and corrosion etc. In hence they were demolished and reconstructed, resulted in waste concrete particles. In this paper, waste concrete particles (WCP) by product from different crushing and selecting process were used in soil cement-based pavement in the various recycling. For using WCP in soil cement-based pavement, the Qualities, physical and chemical properties, of WCP should be researched. In the first step, the specified compressive strength of mortar for two types of clay sand soil and clay soil respectively was experimented to be 15 Mpa and then optimum mixing ratio of chemical solidification agent were decided in the range of $1.5\~3.0\%$ in the replacement with cement weight content. In the second step, based on the prior experimental results, recycling possibility of WCP in soil cement-based pavement was studied. In the result of experiment the mixing ratio of WCP were 5, 10, 15 and $20\%$ in the replacement with soil weight and the compressive strength of mortar was somewhat decreased according to the increase of the mixing ratio of WCP.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.388-394
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• 1998

In this study, the influence of soil contaminant on the cement solidification treatment was considered. Unconfined compression strength(UCS) test was carried out for solidificated specimen, Setting time was measured for cement slurry that was mixed with leachate and wastewater. It was appeared that treatment effect were affected by the the kind of soil, organic content, component of pore water and its concentration. And UCS of samples which were cured in the leachate were decrease about l/5. Especially for the marine clay, UCS of samples which were cured in leachate during 180 days were smaller than 90 days cured samples in the case of cement mixing ratio 5%, 10%.