• Title, Summary, Keyword: Porous ratio

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A Fundamental Study on the Development of Porous Concrete for Planting (식재용 다공질 콘크리트의 개발에 관한 기초적 연구)

  • 윤기원;이상태;김기철;황정하;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.912-915
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    • 1998
  • As a fundamental study on the development of porous concrete for planting, this study is designed to present the properties of porous concrete by varying the kinds of cement, paste to aggregate ratio and dosage of AE admixture. As the results of experiment, the void volumes show 30~33%, 25~ 28% and 17~22% respectively, with paste to aggregate ratio of 20%, 30% and 40%. And unit weight is 1700~1900kg/㎥ while compressive strengths 40~60, 8 0~100 and 120~150kg/$\textrm{cm}^2$. pH of concrete shows a sufficient value at which the plant could grow, when the concrete is permeated in Ammonium Phosphate Dibasic for more than 1 hour. In brief, it shows a possibility of development of porous concrete if the concrete is permeated with permeating in Ammonium Phosphate Dibasic for more than 1 hour when the blast furnace slag cement is used.

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An Experimental Study on the Strength Development of Porus Concerte according to the Mixing Ratio of Aggregate. (골재의 혼합비율에 따른 포러스콘크리트의 강도 증진을 위한 실험적 연구)

  • 김재환;유범재;백용관;김규용;박정호;김무한
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.253-256
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    • 2000
  • The functions of porous concrete were influenced by continuous void, and it differ greatly from the distribution and size shape of continuous void in the same void volume. And porous concrete has been few used because the strength level of porous concrete is lower than that of ordinary concrete at the present time. So the purpose of this study is to increase the strength of porous concrete at the range of satisfying its function, analyze those effects of the mixing ratio of aggregate, affecting the development of its strength.

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Effect of Si/Si3N4 Ratio on the Microstructure and Properties of Porous Silicon Nitrilde Prepared by SHS Methode (규소/질화규소 비가 자전연소합성공정을 이용한 다공질 질화규소 세라믹스의 미세구조와 특성에 미치는 영향)

  • Kim, Dong-Baek;Park, Dong-Soo;Hahn, Byung-Dong;Jung, Yeon-Gil
    • Journal of the Korean Ceramic Society
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    • v.44 no.6
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    • pp.338-342
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    • 2007
  • Porous silicon nitride ceramics were prepared by SHS (Self-Propagating High Temperature Synthesis) from silicon powder, silicon nitride powder and pore-forming precursor. The microstructure, porosity and the flexural strength of the porous silicon nitride ceramics were varied according to the Si/Si3N4 ratio, size and amount of the pore-forming precursors. Some sample exhibited as high flexural strength as $162{\pm}24\;MPa$. The high strength is considered to result from the fine pore size and the strong bonding amoung the silicon nitride particles.

Application of hyperbolic shear deformation theory to free vibration analysis of functionally graded porous plate with piezoelectric face-sheets

  • Arefi, M.;Meskini, M.
    • Structural Engineering and Mechanics
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    • v.71 no.5
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    • pp.459-467
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    • 2019
  • In this paper, hyperbolic shear deformation theory is used for free vibration analysis of piezoelectric rectangular plate made of porous core. Various types of porosity distributions for the porous material is used. To obtain governing equations of motion, Hamilton's principle is used. The Navier's method is used to obtain numerical results of the problem in terms of significant parameters. One can conclude that free vibration responses are changed significantly with change of important parameters such as various porosities and dimensionless geometric parameters such as thickness to side length ratio and ratio of side lengths.

Facile fabrication of porous Sn-based catalysts for electrochemical CO2 reduction to HCOOH and syngas

  • Kim, Hyenki;Lee, Hyunju;Lim, Taeho;Ahn, Sang Hyun
    • Journal of Industrial and Engineering Chemistry
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    • v.66
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    • pp.248-253
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    • 2018
  • Porous Sn and Sn-based binary catalysts are facilely fabricated by an electrodeposition method. Varying conditions for Sn electrodeposition enables a control of Sn roughness, which exhibits a significant effect on catalytic performance for electrochemical $CO_2$ reduction. At a specific applied potential, the porous Sn catalyst with relative roughness factor of 56.5 demonstrates a HCOOH Faradaic efficiency of 40.7% with a $H_2/CO$ ratio of 2.2. Further improvement of the HCOOH Faradaic efficiency to 59.2% is achieved by using a porous $Sn_{0.29}In_{0.71}$ catalyst. This catalyst also achieves a $H_2/CO$ ratio of 2.2, which can be used as syngas to produce value-added hydrocarbons.

Finishing methods and compressive strength-void ratio relationships of in-situ porous concrete pavement

  • Hatanaka, Shigemitsu;Mishima, Naoki;Nakagawa, Takeshi;Morihana, Hirotomo;Chindaprasirt, Prinya
    • Computers and Concrete
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    • v.10 no.3
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    • pp.231-240
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    • 2012
  • In this paper, the effect of finishing methods on the relationships between compressive strength, permeability and void ratio of porous concrete (POC) or pervious concrete is discussed, using core specimens taken from actually constructed POC pavement. To attain reliable performance in the construction work, a newly designed finisher for POC is developed, and the performances as well as methods for controlling void ratio are examined. The POC pavements were finished with three finishing methods viz., no finishing, finishing with standard compactor and finishing with prototype compactor. The results show that the prototype POC finisher is efficient in controlling the void ratio and the quality of POC pavements. The relationships between compressive strength as well as permeability and void ratio of the in-situ POC pavements finished by the prototype machine were obtained. They are slightly different from the laboratory test results owing mainly to the mold effect and the differences in compaction modes.

Properties of Porous Concrete with Pressurized Compaction Method (가압다짐에 의한 포러스콘크리트의 특성에 관한 연구)

  • Cho, Sung-Bae;Kim, Hee-Cheul;Kwak, Byung-Hu;Ng, Ninh-Thuy;Kwon, Hyug-Moon
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.656-659
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    • 2004
  • In this research, the properties of porous concrete by pressurized compaction, such as compressive strength, coefficient of permeability, void ratio of the porous concrete are measured. These results suggest the fundamental data of porous concrete properties.

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Sound Absorbing Characteristics of Porous Concrete according to Mixing Factor (배합요인에 따른 포러스 콘크리트의 흡음특성)

  • 이준;박승범;권혁준;김경훈;장영일;김형석
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.489-492
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    • 2003
  • The results of an experiment on the sound absorption of the porous concrete and its influence on the compressive strength are reported in this paper. Two different sizes of coarse aggregate of 5~13, 13~20mm, and the design void ratio of 20, 25 and 30 percent for a given size of aggregate were used. In the compressive strength, an aggregate of the size of 5~13mm is much higher strength than that of the 13~20mm, In the sound absorption experiment, the size of aggregate of 5~l0mm is much higher sound absorption than that of the 13~20mm. The sound absorption ratio was increased as the design void ratio. As a result, Porous concrete sufficiently have the performance of sound absorption.

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Studies on the Durable Properties of Porous Concrete for Permeable Pavement using Polymer (폴리머를 혼입한 투수성 포장용 콘크리트의 내구성능에 관한 실험적 연구)

  • Park Seong Bum;Seo Dae Seuk;Lee Byung Jae;Song Jae Lib;Son Sung Woo;Cho Kwang Yeon
    • Proceedings of the Korea Concrete Institute Conference
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    • pp.703-706
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    • 2005
  • This study is analyzed mechanical properties and durability of pavement of a road permeability porous concrete to mix polymer for the enhance of porous concrete of performance and durability. As a result, void ratio showed the tendency which the mixing rate of polymer is decreased a little as increased. And, the influence of void ratio according to the kind of polymer has the difference, but void ratio showed the tendency which the mixing rate of polymer is decreased a little as increased. Compressive strength showed the tendency which the mixing rate of polymer is increased a little as increased. but, it showed the tendency to be reduced rather when above $20\%$ it mixed polymer mixing rate $10\%$ at apex.

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Effect of Reinforcing Fiber on Mechanical Properties and Chemical Resistance of Porous Concrete with Hwang-toh (황토를 포함한 다공성 식생콘크리트의 역학적 특성 및 내약품성에 미치는 보강섬유의 효과)

  • Lee, Jin-Hyung;Park, Chan-Gi;Park, Jong-Sik
    • Journal of The Korean Society of Civil Engineers
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    • v.31 no.2A
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    • pp.105-113
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    • 2011
  • This study evaluated the effects of fibers on the mechanical properties and chemical solution resistance of porous concrete with fiber type (jute, pulp, PVA and nylon fiber) and fiber volume fraction (0.0%, 0.1%, 0.2%, 0.3%). The tests that were carried out to analysis the properties of porous concrete included compressive strength, void ratio, pH value, and chemical solution exposure with varying type and volume fraction of fiber were conducted. The type and volume fraction of fiber also affected the void ratio, compressive strength, flexural strength and chemical solution exposure. Increased volume fractions of fiber resulted in improved properties of the compressive strength, flexural strength and void ratio. However, the difference between the measured pH value and chemical resistance of porous concrete with fiber type and volume fraction was not significant.