• Title/Summary/Keyword: slurry method

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Prediction of Wear Depth Distribution by Slurry on a Pump Impeller

  • Sugiyama, Kenichi;Nagasaka, Hiroshi;Enomoto, Takeshi;Hattori, Shuji
    • International Journal of Fluid Machinery and Systems
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    • v.2 no.1
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    • pp.21-30
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    • 2009
  • Slurry wear with sand particles in rivers is a serious problem for pump operation. Therefore, a technique to predict wear volume loss is required for selecting wear resistant materials and determining specifications for the maintenance period. This paper reports a method for predicting the wear depth distribution on the blade of an impeller. Slurry wear tests of an aluminum pump impeller were conducted. Prediction results of wear depth distribution approximately correspond with the results of slurry wear tests. This technique is useful for industrial application.

A Study on Ice Slurry Production by Water Spray

  • Kim, Byeong-Sun;Lee, Yoon-Pyo;Yoon, Seong-Young;Lee, Jin-Ho
    • International Journal of Air-Conditioning and Refrigeration
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    • v.6
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    • pp.45-55
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    • 1998
  • A theoretical and experimental study is performed to investigate the characteristics of ice slurry product. By diffusion-controlled evaporation model the possibility of ice slurry is theoretically anticipated. The water vapor evaporated from the surface of droplets is extracted continuously from the chamber by a vacuum pump. The droplet diameter is measured by silicon immersion method. The ice slurry is obtained by spraying droplets of ethylene glycol aqueous solution in the chamber where pressure is maintained under the triple point of water. The droplet with the diameter of 300 $\mu\textrm{m}$and the initial temperature of 2$0^{\circ}C$ was changed into ice particle within the chamber of 1.33m in height.

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A Study on the Compression of Construction Period by the Improvement of Trench Excavation for Slurry Wall Method (지하연속벽 시공 시 트렌치 굴착방법 개선을 통한 공기단축에 관한 연구: 현장적용사례를 중심으로)

  • Lee, Young Soo;Park, Hyung-Keun;Kang, Kyubyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.5D
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    • pp.499-505
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    • 2012
  • As the excavation depths during excavation works in urban sites are getting deeper and bigger, It is necessary to study for the improvements to solve the problems in the excavation processes. This research deals with the excavation method that can not only minimize the effect on the surrounding constructions, but also shorten the construction period of the excavation work. For this research, there have been an extensive literature review of the bibliographic data about Slurry Wall Method, which is recognized around the world, and the analysis of the major problems in the existing ineffective construction step. These efforts led to the technical improvements. Accordingly, a new construction method applied with the new technical factors has been suggested, and it was possible to compare Slurry Wall Method with the construction method and analyze them on the base of the examples using the suggested method. This new method decreased the excavation period by 15 days. It took only 33days to finish the excavation work, as compared to 48 days that can be seen on the pre-modification schedule. Furthermore, the suggested method in this research is safer, more economically feasible, and better for the environment than Slurry Wall Method. It will contribute to shortening the construction period of Slurry Wall Method in the end.

Field Performance Evaluation of Micro-surfacing Method and Polymer Slurry Seal Method Used in National Highway (일반국도에 적용한 마이크로서페이싱공법과 폴리머슬러리실공법에 대한 현장 공용성 평가)

  • Son, Hyeon Jang;Kim, Yong Joo;Baek, Jong Eun;Lim, Jae Kyu;Kim, Boo Il
    • International Journal of Highway Engineering
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    • v.17 no.1
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    • pp.17-24
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    • 2015
  • PURPOSES : Recently, crack, rutting, and stripping problems from the surface of asphalt pavements in National highway are observed and they affect the drivers to feel uncomfortable on the road. Surface treatments are recommended to use in distressed pavements due to cost-effective, and improvement of surface performance. The purpose of this study is to evaluate the performance of micro-surfacing and polymer slurry seal treatments for distressed asphalt pavements. METHODS : Surface conditions and friction resistance are evaluated for asphalt pavements treated with micro-surfacing and polymer slurry seal mixes in National highway 30 line and 34 line. Visual observation is conducted and surface performance is measured by PES (Performance Evaluation Surveyor) in terms of crack ratio, rutting and IRI(International Roughness Index). BPN(British Pendulum Number) is measured by BPT(British Pendulum Tester) to evaluate the friction resistance in the field. RESULTS : The surface evaluation results are presented for asphalt pavement treated with micro-surfacing and polymer slurry seal treatments in National highway 30 line and 34 line. Based on the visual observation, micro-surfacing and polymer slurry seal treatments show better improvements in terms of cracks and stripping. Based on the surface conditions measured by PES vehicle, the surface performance of micro-surfacing treatments improves from 53.3% to 54.2% and the surface performance of polymer slurry seal treatments improves from 21.6% to 59.7%. However, the friction resistance of both micro-surfacing and polymer slurry seal treatments decreases from 2.5% to 6.7%. Further, it should be verified to produce the surface exposed with aggregates during the construction process of both treatment methods in the field. CONCLUSIONS : Based on the performance evaluation results in the filed, the surface performance of asphalt pavement treated with micro-surfacing and polymer slurry seal treatments improves from 21.6% to 59.7%. While, the friction resistance of asphalt pavement treated with micro-surfacing and polymer slurry seal treatments does not improve. It can be concluded that current micro-surfacing and polymer slurry seal treatments would improve surface performance but would not improve the friction resistance.

Shear Resistance Performance of Vertical Construction Joints in Slurry Walls Using Concrete Shear Keys (콘크리트 전단키에 의한 지하연속벽 수직시공이음부의 전단저항 성능)

  • Lee, Jeong-Young;Kim, Seung-Weon;Kim, Doo-Kie
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.399-400
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    • 2023
  • Current building structural standards require the shear strength and rigidity in the design of vertical construction joints in a slurry wall. This paper proposes a shear key resistance method for shear connection of vertical construction joints, and compares its structural performance with the currently prevalent method of shear friction rebar. The study found the structural performance of the shear key resistance method was significantly better than that of the shear friction rebar method.

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Holdup Characteristics of Small Bubbles in a Viscous Slurry Bubble Column (점성슬러리 기포탑에서 작은 기포의 체류량 특성)

  • Jin, Hae-Ryong;Song, Yang-Ho;Kang, Yong;Jung, Heon;Lee, Ho-Tae
    • Korean Chemical Engineering Research
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    • v.49 no.1
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    • pp.83-88
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    • 2011
  • Holdup characteristics of small bubbles were investigated in a viscous slurry bubble column. The phase holdup of small bubbles was obtained from the knowledge of total bubble(gas) holdup and large bubble holdup, which were measured by mean of static pressure drop method and dual resistivity probe method, respectively. Effects of gas velocity, viscosity of continuous liquid phase and solid fraction in the slurry phase on the small bubble holdup as well as holdups of total bubble(gas) and large bubble in a viscous slurry bubble column. The small bubble holdup increased with increasing gas velocity but decreased with increasing liquid viscosity or solid fraction in the slurry phase. In addition the fraction of small bubble in the total bubble(gas) holdup increased with increasing gas velocity but decreased with increasing liquid viscosity or solid fraction in the slurry phase. It was revealed that the rising velocity of large bubble did not related to the holdup of small bubble in a viscous slurry bubble column.

Rapid and Simultaneous Determination of Volatile Fatty Acids and Indoles in Pig Slurry and Dog Excrement by Solid-Phase Micro-Extraction Method with Gas Chromatography

  • Kim, Hyun-Jung;Yu, Mee-Seon;Yang, Sung-Bong
    • Journal of Environmental Science International
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    • v.23 no.10
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    • pp.1693-1701
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    • 2014
  • A rapid and simple method for the quantitative determination of volatile fatty acids (VFAs; propionic acid, n-butyric acid, i-valeric acid and n-valeric acid) and indoles (phenol, p-cresol, 4-ethyl phenol, indole and skatole) in pig slurry and dog excrement using solid-phase micro-extraction (SPME) coupled to gas chromatography was evaluated. $50/30{\mu}m$ DVB/CAR/PDMS (Divinylbenzene/Carboxen/Polydimethylsiloxane) fiber was used to extract the target compounds in aqueous media. Sample amount and adsorption time was standardized for the routine analysis. Detection limits were from 0.11 to $0.15{\mu}gL$ for VFAs and from 0.12 to $0.28{\mu}gL$ for indoles and the correlations observed ($R^2$) were 0.975~1.000. This method was applied to the pig slurry, fertilizer, compost and dog excrement. In nearly all cases, the indoles were detected in concentrations of higher than their limits of detection (DOLs). But the VFAs in swine manure were below their DOLs.

Design Considerations and Method for Vertical Construction Joints of Slurry Walls Used as Permanent Basement Walls (영구벽체로 사용하는 지하연속벽 수직시공이음부의 설계방법)

  • Lee, Jeong-Young;Kim, Seung-Weon;Kim, Doo-Kie
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.395-396
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    • 2023
  • The current building structural standards present design requirements for the vertical construction joint of a slurry wall when it is used as a permanent wall. This paper proposes design methods and considerations according to the requirements of the relevant standards.

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Force-Displacement Relationship Diagram for Shear Connections in Vertical Construction Joints of Slurry Walls (지하연속벽 수직시공이음부의 전단접합부에 대한 힘-변위 상관도)

  • Lee, Jeong-Young;Kim, Seung-Weon;Kim, Doo-Kie
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.397-398
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    • 2023
  • To design the shear connections for vertical construction joints of slurry walls, it is necessary to create a force-displacement curve that represents the structural performance of the shear connections. This paper proposes a method for preparing the force-displacement curve of the shear connections including major considerations.

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Constructability Evaluation of Seismic Mechanical Splice for Slurry Wall Joint Consisting of Steel Tube and Headed Bars (슬러리월의 내진설계를 위한 강재각관과 확대머리 철근으로 구성된 기계적 이음의 시공성 평가)

  • Park, Soon-Jeon;Kim, Dae-Young;Lim, In-Sik
    • Journal of the Korea Institute of Building Construction
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    • v.23 no.3
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    • pp.295-303
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    • 2023
  • South Korea has recently witnessed an increasing number of seismic events, leading to a surge in studies focusing on seismic earth pressures, as well as the attributes of geological layers and ground where foundations are established. Consequently, earthquake-resistant design has become imperative to ensure the safety of subterranean structures. The slurry wall method, due to its superior wall rigidity, excellent water resistance, and minimal noise and vibration, is often employed in constructing high-rise buildings in urban areas. However, given the separation between panels that constitute the wall, slurry walls possess limited resistance to seismic loads in the longitudinal direction. As a solution, several studies have probed into the possibility of interconnecting slurry wall panels to augment their seismic performance. In this research, we developed and evaluated a method for linking slurry wall panels using mechanical joints, including concrete-confined steel pipes and headed bars, through mock-up tests. We also assessed the constructability of the suggested method and compared it with other analogous methods. Any challenges identified during the mock-up test were discussed to guide future research in resolving them. The results of this study aid in enhancing the seismic performance of slurry walls through the development of an interconnected panel method. Further research can build on these findings to address the identified issues and improve the efficacy and reliability of the proposed method.