• Geomechanics and Engineering
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• 제37권4호
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• pp.419-429
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• 2024

The primary goal was to assess how the addition of cement dust, a byproduct known to be harmful, could be used to stabilize clay. Various percentages of cement dust were added to soil samples, which were then subjected to triaxial testing at different rates of strain using an unconsolidated undrained triaxial machine. Six different rates of strain were applied to analyze the response of the clay under different conditions, resulting in 216 triaxial sample tests. As the percentage of cement dust in the clay samples increased, there was a noticeable increase in the strength properties of the clay, indicating a positive effect of cement dust on the clay's strength characteristics. Higher rates of strain during testing led to increased strength properties of the clay. Varying cement dust content influenced the impact of increasing the rate of strain on the clay's strength properties. Higher cement dust content reduced the sensitivity of the clay to changes in strain rate, indicating that the clay became less responsive to changes in strain rate as cement dust content increased. Potential for Clay Stabilization Cement dust proved the potential to enhance the strength properties of clay, indicating its potential utility in clay stabilization applications. Both higher percentages of cement dust and higher rates of strain were found to increase the clay's strength. It's essential to consider both the percentage of cement dust and the rate of strain when assessing the strength properties of clay in practical applications.

• 환경위생공학
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• 제18권4호
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• pp.36-44
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• 2003

The cement-based system among S/S(Solidification/Stabilization) is widely used to treat hazardous wastes. In this study, tannery sludge was solidified to evaluate the stabilization effects of using admixtures in the cement-based S/S. Fly ash as substitute also used to increase the strength of the S/S of hazardous waste. The compressive strength measurement and leaching experiment of chromium metal of solidified mortar were carried out to compare and evaluate the physical and chemical characteristics of solidified hazardous waste sludge. From the result of this study, there was increased of compressive strength by using AEW-3(early-hardening AE water reducing agent), and leaching concentration of chromium became low enough to satisfy the regulatory criteria. The successful solidification for the organic contaminant and heavy metal in hazardous waste should enable to treat by cement-based system using early-hardening AE water reducing admixture and fly ash as substituted cement.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.289-294
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• 2001

This study concerns the cement-solidification/stabilization of the waste with high concentration heavy metals. Compressive strength and leaching test of heavy metals were evaluated for ing types of cements and the effect of the additives of Hauyne clinker and slag were also cussed. Using ordinary portland cement, rapid hardening portland cement and the cement with additives solidification materials, it shows that the strength and stability of concrete is satisfactory and superiority is in the order of rapid hardening portland cement > the cement with additives > nary portland cements.

• Advances in environmental research
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• 제3권4호
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• pp.337-353
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• 2014

The determination of the effectiveness of the immobilization of blasting dust (waste generated in galvanic activities) in cement matrix, as well of mechanical, physical and microstructural properties of concrete paving blocks produced with partial replacement of cement was the objective of this work. The results showed that blasting dust has high percentage of silica in the composition and very fine particle size, characteristics that qualify it for replacement of cement in manufacturing concrete blocks. The replacement of Portland cement by up to 5% residues did not cause a significant loss in compressive strength nor increase in water absorption of the blocks. Chemical tests indicated that there is no problem of leaching or solubilization of contaminants to the environment during the useful life of the concrete blocks, since the solidification/stabilization process led to the immobilization of waste in the cement mass. Therefore, the use of blasting dust in the manufacture of concrete paving blocks is promising, thus being not only an alternative for proper disposal of such waste as well as a possibility of saving raw materials used in the construction industry.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회 논문집(II)
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• pp.1199-1204
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• 2000

This study concerns the cement-solidification/stabilization of the municipal waste incineration fly-ash. Compressive strength and leaching test of heavy metals were evaluated for varying types and ratios of cements and the effects of some additives of Hauyne clinker and slag were also discussed. In the cases of using cement binders more than 10%, the compressive strength after 3 days showed the values over $20kgf/cm^2$. Type III cement and Hauyne clinker improved the compressive strength, especially early strength. And the values of leaching test showed that cement-solidification is effective method to stabilize heavy metals especialy when using type III cement and adding Hauyne clinker and slag,.

• Computers and Concrete
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• 제20권2호
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• pp.145-154
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• 2017

In geological engineering, grouting with Portland cement is a common technique for ground improvement, during which micro-fine cement is applied as a slurry, such that it intrudes into soil voids and decreases soil porosity. To determine the utility and behavior of cements with different Blaine values (index of cement particle fineness) for stabilization of fine sand, non-destructive and destructive tests were employed, such as laser-ray determination of grain size distribution, and sedimentation, permeability, and compressive strength tests. The results of the experimental study demonstrated a suitable mix design for the upper and lower regions of the cement-grading curve that are important for grouting and stabilization. Increasing the fineness of the cement decreased the permeability and increased the compressive strength of grouted sand samples considerably after two weeks. Moreover, relative to finer (higher Blaine value) or coarser (lower Blaine value) cements, cement with a Blaine value of $5,100cm^2/g$ was optimal for void reduction in a grouted soil mass. Overall, study results indicate that cement with an optimum Blaine value can be used to satisfy the designed geotechnical criteria.

• 대한환경공학회지
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• 제30권10호
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• pp.1034-1038
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• 2008

분해성 고형화/안정화(DS/S, degradative solidification/stabilization)는 전통적인 고형화/안정화(S/S, Solidification/Stabilization)에 경제성과 유기 오염물질의 분해를 추가한 기술이다. 무기 오염물질은 고정되며 유기 오염물질은 DS/S시스템에 의해 분해된다. 본 연구에서는 액상폐기물 내의 클로로포름(CF)과 메틸렌클로라이드(MC) 분해를 위해 cement/slag/Fe(II)시스템을 바인더로 한 DS/S의 효율성을 평가 하였다. 초기 CF의 농도는 0.26 mM, 1.0 mM, 8.4 mM, 25 mM and 42 mM 그리고 Fe(II) 농도는 200 mM로 하였다. 실험결과 다양한 농도의 CF의 분해경향은 유사일차반응으로 표현할 수 있었으며 초기농도 0.26 mM에서 5일 이내에 95%가 분해되었다. MC의 분해를 촉진시키기 위하여 중금속 50 mg/L을 추가하였으나 분해는 거의 이루어지지 않았다. 따라서 MC의 분해를 위해서 추가적인 고찰이 필요하다고 판단되며 다른 반응 경로의 부산물에 대한 추가적인 고찰을 통해 cement/slag/Fe(II)에서 메탄 계열의 염소계유기화합물의 명확한 분해 경로와 메카니즘을 파악할 수 있을 것이다.

• Geomechanics and Engineering
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• 제23권1호
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• pp.31-38
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• 2020

Soil-cement stabilization is a type of ground improvement method which has been used to improve the engineering properties of soil. The unconfined compression test is the commonly used method to evaluate the quality of the stabilized soil due to its simplicity, reliability, rapidity and cost-effectiveness. The main objective of this study was to evaluate the effect of recovered carbon black (rCB) on the strength characteristic of cement-stabilized sand. Various rCB contents and water to cement ratios (w/c) were examined. The unconfined compression test on stabilized sand with different curing times was also conducted for a reconstituted specimen. From the test result, it was found that the compressive strength of cement-stabilized sand increased with the increase of the rCB content up to 3% and the curing time and with the decrease of the w/c ratio, showing that the optimum rCB concentration of the tested stabilized sand was around 3%. In addition, a prediction equation was suggested in this study for cement-stabilized sand with rCB as a function of the w/c ratio and rCB concentration at 14 and 28 days of curing.

• 한국환경농학회지
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• 제29권1호
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• pp.47-53
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• 2010

본 연구에서 비소로 오염된 토양에 함유된 비소를 안정화시키기 위하여 4종류의 안정화제를 이용 처리하여 다음과 같은 결론을 얻었다. 안정화 처리에 사용된 오염토는 약알칼리성을 띄고 있으며, 입도분포 결과 사토계열이였고 57.5%의 비소가 무정형 및 비결정형 철/알루미늄 수산화물형태로 존재했다. 안정화 실험 결과 소석회/포틀랜드시멘트 혼합 안정화처리가 모든 안정화 처리와 비교 했을 때 현저한 우의를 보였으며 총 함량 30%로 토양오염 우려기준 20 mg/kg('나'지역)을 통과 하였다. 소석회/$FeCl_3{\cdot}6H_2O$ 혼합 이용시 효율적인 비소 저감효과룹 기대할 수 없었으며 소석회/NaOH는 효과적이었으나 소석회/포틀랜드시멘트 보다는 효율성이 제한적 이였다. 소석회/포틀랜드시멘트 혼합 안정화 처리 후 연속추출결과는 처리 전 오염토와 비교했을 때 특이적 흡착과 잔류대의 증가를 보였다. 특히 25wt%+10wt% 처리 시료에서 잔류태의 증가는 2배가 넘어 (16%에서 35.7%) 매우 안정적인 비소 존재 형태를 보여 비소 용출농도 저감에 현저하게 기여한 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.233-236
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• 2002

다양한 산업활동에 의하여 발생하는 6가 크롬 (Cr(Ⅵ))은 대표적인 토양 및 지하수 오염물질이다. Cr(Ⅵ)은 3가크롬(Cr(III))로의 환원에 의한 침전반응으로 이동성이 저하된다고 알려져 있다. 본 연구에서는 기존의 고형화/안정화 공정에 환원.분해 반응을 추가한 2가철 기반 분해성 고형화/안정화(Degradative Solidification/Stabilization)공정에 의한 Cr(Ⅵ) 처리 특성을 고찰하였다. 회분식 실험결과 cemen/Fe(II) system내에 Cr(Ⅵ)은 환원반응 뿐만 아니라 cement에 의한 침전에 의해서도 제거됨이 밝혀졌다. Cr(Ⅵ)의 제거속도는 Fe(II)의 반응당량에 비례하는 것으로 보여진 반면, cement/solution ratio에 따른 Cr(Ⅵ) 제거동역학의 차이는 그다지 크지 않았다