• 제목/요약/키워드: Strength Property

검색결과 2,661건 처리시간 0.023초

표면강도 향상제 내첨에 따른 수초지 특성 변화 (Handsheet Property Changes by Internal Addition of Surface Strength Agent)

  • 임종혁;정철헌;채희재;박창순;박종문
    • 펄프종이기술
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    • 제42권2호
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    • pp.41-45
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    • 2010
  • This study was performed to evaluate the effect of paper property changes by internal addition of surface strength agent on printability. Advances in printing technique has required the development of paper qualities in many aspects. Basically paper structure is composed of hydrogen bonds which induce many problems in high speed printing machine because of weak bonding strength. One of the important printing problems is surface picking when mechanical pulp or recycled pulp are used. It was caused by the ink-stained blanket in printing process because accumulations of pollutant in white water and other elements which are bonded weakly or do not have hydrogen bonds. Debris at paper surface adheres to blanket which deteriorates printing efficiency and causes various problems. To complement these problems, Pennocel 5137 of polysaccharide structure was used as an agent to improve paper's surface property, strength and printability. Paper surface picking was analyzed by RI-1 test. As the dosage amount increased tensile strength, fiber bonding strength and ZDT strength were improved. Further more formation, smoothness and surface picking resistance were improved. It was confirmed that when adding polysaccharide structure polymers to improve surface strength such as surface picking resistance, it was also possible to improve tensile strength, fiber bonding strength, formation and smoothness.

콘크리트의 공극 특성에 관한 실험적 연구 (An Experimental Study on the Concrete Pore Structure Property)

  • 이문환;정미경;오세출;서치호
    • 한국구조물진단유지관리공학회 논문집
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    • 제3권4호
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    • pp.179-189
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    • 1999
  • This study attempts to propose an evaluation considering the property of concrete pore which affects the deterioration of neutralization and the rebar resistance of concrete. Understanding pore property of concrete in using extent, for practical using of concrete manufacturing condition. basic quality property and durability estimation etc, the results of the experiment are as follows. 1) The result of analysis pore property of every specimen with the method of area ratio, in limitation of $10^{-6}{\sim}10^{-5}m$, the pore distribution ratio was maximum. It was high value as W/C was increased and the unit cement content was decreased. 2) In case of using admixture. the volume of pores was some increased as variation of mixing content. In high W/C range, it was very increased compared with plain concrete. 3) Concerned with compressive strength and volume of pores in hardened concrete, it is possible compressive strength estimation using the property of concrete pores. 4) Direct measurement of concrete pore property is difficult. the valuation of the dynamic modulus of elasticity using ultrasonic wave velocity was available. 5) Quantitatively evaluation of concrete structure durability by past result of pore distribution estimation, and it can be estimative scale of property study on the concrete materials.

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소성볏짚을 혼입한 모르타르의 압축강도 특성에 관한 연구 (A Study on the Compressive Strength Property of Mortar using Rice Straw Ash)

  • 정의창;신상엽;김영수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 추계 학술논문 발표대회
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    • pp.265-266
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    • 2012
  • The purpose of this study was to investigate the compressive strength property into mortar using rice straw ash. In an effort to evaluate the effects of rice straw ash firing temperatures on compressive strength properties of mortar, a change in the components of rice straw ash was observed according to firing temperatures, and compressive strength of mortar and X.R.F was measured. As a results, As the mortar with a mixture ratio of rice straw ash up to 15% was found to have a compressive strength superior to that of plain mortar.

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Mortar Characteristics for Reinforcement of Ancient Tomb Murals Using Oyster Shells

  • Lee, Hwa Soo;Yu, Yeong Gyeong;Han, Kyeong Soon
    • 보존과학회지
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    • 제34권4호
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    • pp.295-303
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    • 2018
  • The application of reinforcing agents with hydraulic property and strength development characteristics was studied under conditions similar to those of mural-painting mortar made with oyster shell powder. Reinforcement mortar made with oyster shell powder showed hydraulic properties and strength to supplement the weaknesses of natural hydraulic lime(NHL); this confirmed its possibility as a wall-reinforcing material with enough strength for preserving mural paintings. Reinforcement mortar 1 showed hydraulic property and general characteristics of lime mortar, such as consistency and viscosity, as well as lower strength and higher whiteness compared to an NHL product. For Reinforcement mortar 2, the original wall sample characteristics were reflected by mixing more shell produced through calcination; and it showed similar strength to that of Reinforcement mortar 1 as well as high whiteness. In measuring the contraction ratio of reinforcement mortar samples, Reinforcement mortar 1 and 2 showed more stability in property change compared to the NHL Group.

Constitutive property behavior of an ultra-high-performance concrete with and without steel fibers

  • Williams, E.M.;Graham, S.S.;Akers, S.A.;Reed, P.A.;Rushing, T.S.
    • Computers and Concrete
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    • 제7권2호
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    • pp.191-202
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    • 2010
  • A laboratory investigation was conducted to characterize the constitutive property behavior of Cor-Tuf, an ultra-high-performance composite concrete. Mechanical property tests (hydrostatic compression, unconfined compression (UC), triaxial compression (TXC), unconfined direct pull (DP), uniaxial strain, and uniaxial-strain-load/constant-volumetric-strain tests) were performed on specimens prepared from concrete mixtures with and without steel fibers. From the UC and TXC test results, compression failure surfaces were developed for both sets of specimens. Both failure surfaces exhibited a continuous increase in maximum principal stress difference with increasing confining stress. The DP tests results determined the unconfined tensile strengths of the two mixtures. The tensile strength of each mixture was less than the generally assumed tensile strength for conventional strength concrete, which is 10 percent of the unconfined compressive strength. Both concretes behaved similarly, but Cor-Tuf with steel fibers exhibited slightly greater strength with increased confining pressure, and Cor-Tuf without steel fibers displayed slightly greater compressibility.

일렉트로 가스 용접부의 기계적 성질에 미치는 Mn 및 입열량의 영향 (Effects of Mn and Heat-input on the Mechanical Properties of EGW Welds)

  • 김남인;정상훈;이정수;강성원;김명현
    • 대한금속재료학회지
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    • 제47권3호
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    • pp.195-201
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    • 2009
  • This paper is concerned with effects of Mn and heat-input on the mechanical properties of EGW welds. Four different kinds of welding consumables were fabricated by varying Mn contents such as 1.3, 1.5, 1.7, 2.0%Mn and each consumable was welded for EGW on four heat-input conditions between 190 and 340 KJ/Cm. Mn contents were decreased as heat-input increases and alloy elements (C, Si, Ti, B, Al) to deoxidize easily also revealed similar tendency to Mn. Their microstructure, Charpy impact property and strength were investigated, and it is found that Charpy impact property and strength exhibit a strong dependence on change of microstructure by Mn contents and heat-input. The increase of Mn contents or the decrease of heat-input made the microstructure fine and increase volume fraction of acicular ferrite, thereby leading to the great improvement of Charpy impact property and strength. In case of single EGW, optimum Mn contents are over 1.7% for the toughness and strength.

0.19C - 1.17Cr 강의 냉간인발조직과 기계적 성질 (The Microstructure and Mechanical Property of 0.19C-1.17Cr Steel with Cold Drawing)

  • 신정호;장병록
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 제4회 압출 및 인발가공 심포지엄
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    • pp.85-90
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    • 2001
  • The microstructure and mechanical property of 0.19C-1.17Cr steel were investigated with cold drawing. This commercial steel has the microstructure that is consist of ferrite and pearlite. The tensile and yield strength are increased as the reduction ratio of cold drawing is increased. It was clear that mechanical properties could be improved by combination of the heat treatments and reduction ratio. Yield strength. tensile strength, and impact value were formulated as a constitutive function of cold drawing ratio, respectively.

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고강도 콘크리트를 이용한 CFT 기둥의 충전성 연구 (A study on the Packing ability of Concrete Filled in Steel Tube Column by High Strength Concrete)

  • 강용학;조상영;정근호;백민수;김진호;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.991-996
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    • 2002
  • In this study, there are kind of property experiments like fluidity, compressive strength, bleeding measurement, concrete sink for CFT use high fluidity concrete. The property difference between before transmit and after transmit concrete in the mock up test with ready mixed concrete equipment is examined. The variable factors in mock up are diaphragm existence and nonexistence, diaphragm placing hole sizes. To investigate the concrete property under diaphragm, concrete packing ability tests is peformed. High fluidity and strength concrete which satisfied with mix criteria could apply to building construction field. It it is quality managed with use of packing ability analysis.

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Full-Grain 피혁용 수용성 아크릴 Base coat 수지의 합성 및 물성측정 연구 (A Study of Synthesis and Mechanical property measurement for Waterborne Acrylic Base coat Resin in Full-Grain Leather)

  • 이주엽;김기준
    • 한국응용과학기술학회지
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    • 제28권3호
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    • pp.359-366
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    • 2011
  • In this study we experimented that how polyurethane effect to acrylic-polyurethane resin in Full-Grain leather coatings. First of all, we consummated waterborne acrylic emulsion and waterborne polyurethane resin, Than we prepared F.G leathers which were coated by acrylic resin and acrylic-polyurethane resins. According to measured data for solvent resistance, acrylic resin and acrylic-polyurethane resins had good property. Sample a(WAC) had most low strength($2.10kg_f/mm^2$) and sample d(WAC 93 : WPU 7) had most high strength($3.41kg_f/mm^2$). Also we knew that most good property of abrasion is d(47.4 mg). In elongation case, a(WAC) had most good result(645 %) in this experiment.

Fundamental Investigation of Functional Property of Concrete Mixed with Functional Materials

  • Lee, Jong-Chan;Lee, Moon-Hwan;Lee, Sae-Hyun;Park, Young-Sin;Park, Jae-Myung
    • International Journal of Concrete Structures and Materials
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    • 제18권3E호
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    • pp.165-171
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    • 2006
  • Environment-friendly materials are increasingly used as building construction materials nowadays, and the market share of those is growing. Accordingly, the research and developments in terms of environmental value are progressing steadily now. The main characteristics of environmental products are far-infrared radiation, negative-ion emission, electromagnetic wave shielding, and antimicrobial property. These products are often used in mortar and as spray on the finishing material. Nevertheless, there are hardly any research on the functional properties of concrete, the main material in construction field. Thus, we evaluated such basic properties of concrete as slump, compressive strength and air content while using such functional materials as sericite, wood-pattern sandstone, carbon black and nano-metric silver solution to focus on their functional properties like far-infrared radiation, negative ion emission, electro magnetic wave shielding, and antimicrobial activity in this research. The results indicated that the most useful material in the functional materials was carbon black. Sericite and nano-metric silver solution had a little effect on the functional property. Moreover, although wood-pattern sandstone had very high functional property, it exhibited too low compressive strength to be applied, to concrete as a factory product. Antimicrobial property of nano-metric silver solution in the concrete was not clear demonstrated, but if these specimens were to be aged in $CO_2$ gas for a long time, it might be apparent.