• Title/Summary/Keyword: ratio and proportion

Search Result 1,764, Processing Time 0.032 seconds

An Experimental Study on the Properties of Concrete according to G/S ratio classified by Maximum Size of Coarse Aggregate (굵은골재 최대치수별 굵은골재/잔골재 용적비에 따른 콘크리트의 특성에 관한 실험적 연구)

  • Kim, Duk-Hyun;Lee, Sang-Soo;Song, Ha-Young;Kim, Eul-Yong
    • Journal of the Korea Institute of Building Construction
    • /
    • v.4 no.2
    • /
    • pp.97-103
    • /
    • 2004
  • In this study, the experiment was carried out to investigate and analyze the influence of coarse aggregate's mix ratio and maximum size on the properties of concrete. The main experimental variables were water/cement ratio 45% and 65%, coarse aggregate/fine aggregate ratio 90%, 130% and 170%, maximum size of coarse aggregate 15mm, 25mm and 40mm. According to the test results, the principal conclusions are summarized as follows. 1) The slump and flow of fresh concrete were found to be higher in the order of G/S ratio 170%, 130%, 90%, also in the order of maximum size 40mm, 25mm, 15mm. 2) The compressive strength of hardened concrete were found to be higher in the order of G/S ratio 170%, 130%, 90%, also in the order of maximum size 15mm, 25mm, 40mm.

A Fundamental Study on the Mix Proportion of Base Concrete Influencing on the Workability and Engineering Properties of Flowing Concrete (유동화 콘크리트의 시공성 및 공화적 특성에 미치는 베이스콘크리트의 조합조건에 관한 기초적 연구)

  • 김무한;송하영
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1991.04a
    • /
    • pp.29-32
    • /
    • 1991
  • This is the study on the performance of workability and engneering properties of flowing concrete using the superplasticizers, which are being used for control of the consistency of fresh concrete without modifying the properties of the hardened concrete and for production of high quality concrete at a low water-cement ratio. It is the aim of this study to analyze and investigate workability and engineering properties of flowing concrete according to the addition rate in poor and rich mix proportions of base concrete. Base on this fundamental investigation for the development of flowing concrete mix design, it could be drawn that the workability and engineering properties of flowing concreteare influenced greatly by mix proportion and dosage of superplasticizers.

  • PDF

Quality Characteristics of Pound Cake with Added Rubus coreanus Miquel Concentrate (복분자 농축액을 첨가한 파운드케이크의 품질 특성)

  • Ji, Joung-Lan;Jeong, Hyun-Chul
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.23 no.3
    • /
    • pp.341-348
    • /
    • 2013
  • The Rubus coreanus Miquel concentrate was added in 0 (control), 10, 20, 30, and 40% substitution ratios by weight per sugar. The specific gravity and water content in pound cake batter tended to increase specific gravity according to the added Rubus coreanus Miquel concentrate. The volume, weight, and specific loaf volume in pound cake tended to decrease by according to the addition Rubus coreanus Miquel concentrate. Moisture contents in pound cake tended to increase long the addition Rubus coreanus Miquel concentrate. Brix and pH also decreased. 'L' and 'b' along with the increase in 'a' values were followed in proportion to the substitution ratio. Typical textural parameters like hardness, gumminess, and chewiness were increased in proportion to the substitution ratios, but springiness decreased. Adhesiveness and cohesiveness did not show any considerable differences between the pound cakes. The sensory evaluation showed a high preference for pound cake made with 30% Rubus coreanus Miquel concentrate.

Optimum Mixture Proportion of Self-Compacting Concrete Considering Packing Factor of Aggregate and Fine Aggregate Volume Ratio (골재 채움율과 잔골재 용적비를 고려한 자기충전형 콘크리트의 최적배합)

  • 최연왕;정문영;정지승;문대중;안성일
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2002.10a
    • /
    • pp.549-554
    • /
    • 2002
  • In Powder System, SCC demands high dosage of superplasticizer and a lage amout of powder for suitable fluidity and viscosity. Okamura's method of most representative mixing design method in SCC of Powder-System is unfavorable economically because of using a large amount of powder. In addition, many ready-mixed concrete plants do not use his mix design method and procedure due to complexity for practical application. Therefore, Nan Su proposed more simple mix design method than Okamura's. It had an advantage in simplicity in practical application and required a smaller amount of powders compared with Okamura's method. This paper proposed an optimal mixture proportion of SCC with consideration of Nan Su's method. The new and modified mix design method required a smaller amount of powder than that of Nan Su's. To check the properties of SCC, considered with the requirements specified by the Japanese Society of Civil Engineering.(JSCE)

  • PDF

A Study on Risk Selection Behavior of Japanese Households: Focusing on the relationship between income level and hyperbolic discount (日本家計のリスク選択行動に関する研究 - 所得水準と双曲性の関係を中心に -)

  • Yeom, Dong-ho
    • Analyses & Alternatives
    • /
    • v.4 no.1
    • /
    • pp.105-123
    • /
    • 2020
  • This study analyzes the risk selection behavior of Japanese households. The study approaches the view of 'the hyperbolic discount' which is used in behavioral economics based on the rise in mortgage lending by low-income households in the late 2000s. The study focuses on how households risk preferences vary by income levels. The study analyzes the relationship of attitude of household interest rate risk using Binomial Logistic and Heckman two-step estimation method assuming that there are only two types of Adjustable-Rate Mortgage and Fixed-Rate Mortgage. As a result of the empirical analysis, low-income households annual income tend to have a higher proportion of housing debt as same as higher interest rate risk preferences households in proportion to income growth and interest rate risk preferences. Those results indicate that there is possibility of a hyperbolic discount on low-income households in Japan, and support the hypothesis that low-income households are relatively higher household debt ratio because of high utility due to home purchase in the near future (short-term).

  • PDF

A Study on the Similitude of Material for Small-Scale Model Mix Proportion of Concrete Pavement. (콘크리트 포장 축소모델 배합의 재료적 상사성에 관한 연구)

  • 배주성;고영주;김재경;김평수
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1997.10a
    • /
    • pp.103-110
    • /
    • 1997
  • The objective of this study is to provide the information on the small-scale model mix proportion when the behavior of prototype concrete pavement is studied through small-scale model experiments. However it is difficult to obtain a model material to simulate the prototype concrete by scaling the individual components according to the laws of similitude. In this paper, the stress-strain behavior in uniaxial compression is used as a means to correlate materials similitude between the prototype and the model concrete. Based on th results of experiments, We compared the stress-strain curves of prototype and model concrete mixes using a nondimensional basis. In order to simulate the stress-strain curves of prototype concrete, it is important that various mix as of model concrete selected properly which are varied from aggregate grading, cement-aggregate and sand-aggregate ratio.

  • PDF

Bond Performance Test for Optimum Mixing Ratio Calculation of the Floatig Floor Method on Roof-top (옥상 뜬바닥 구조공법의 접착제 최적 배합비 산정을 위한 부착성능 실험)

  • Seo, Yu-Hyun;Park, Jun-Mo;Kim, Ok-Kyue;Jung, Il-Gi
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2016.05a
    • /
    • pp.111-112
    • /
    • 2016
  • Waterproofing methods for applying to roof-top in the building are various, but it is not enough to development, which are simplified and low-cost method for old building. Especially, these buildings have not only a low insulation, but a disadvantage for energy. A floating floor method is necessary for this. This study performs an experimentt about bonding capacity of complex panel for waterproofing and heat insulation. The bond strength experiment is based on KS F 4716, and it is considered by bond mix proportion about panel and slab.

  • PDF

Comparison of Binocular Function and Surgical Outcomes of Tenacious Proximal Fusion and High Accommodative Convergence/Accommodation Ratio Types of Intermittent Exotropia

  • Park, Jun Woo;Lee, Soo Jung
    • Korean Journal of Ophthalmology
    • /
    • v.32 no.6
    • /
    • pp.483-487
    • /
    • 2018
  • Purpose: To compare the characteristics and surgical outcomes in patients with tenacious proximal fusion (TPF) and high accommodative convergence/accommodation ratio (AC/A) types of intermittent exotropia. Methods: This study retrospectively enrolled 40 patients with intermittent exotropia, 23 with TPF and 17 with high AC/A. Binocular function was evaluated by Worth's 4-dot test. Patients underwent lateral rectus recession, and surgical outcomes were compared. Surgical success was defined as less than ${\pm}10$ prism diopters (PD) at 12 months postoperatively. Results: The proportion of diplopia at near, evaluated by Worth's 4-dot test, was significantly higher in patients with high AC/A than in those with TPF (35.3% vs. 4.3%, p = 0.029). The mean preoperative angles of deviation in TPF and high AC/A types were $28.3{\pm}4.4$ and $28.8{\pm}4.5PD$ at distances, and $14.7{\pm}4.2$ and $15.1{\pm}4.1PD$ at near. Twelve months after surgery, the mean angles of deviation in TPF and high AC/A types were $2.9{\pm}9.8$ and $1.2{\pm}9.6PD$, respectively, at distance and $1.7{\pm}7.7$ and $-1.3{\pm}11.3PD$ at near. The surgical success rates were similar in the TPF and high AC/A types (74.0% vs. 64.7%). Five (21.7%) patients with TPF and 2 (11.8%) with high AC/A type experienced recurrence, with consecutive esotropia occurring in 1 (4.3%) patient with TPF and 4 (23.5%) patients with high AC/A. Conclusions: The proportion of diplopia at near was higher in patients with high AC/A type than in those with TPF intermittent exotropia. However, the surgical success rates were not significantly different between the types.

Effect of Mix Proportion on the Flowing Characteristics of Super-flowing Concrete (초유동 콘크리트의 유동 성능에 미치는 배합요인의 영향)

  • 노재호;한정호;백명종;이보근;박기청
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1994.10a
    • /
    • pp.115-120
    • /
    • 1994
  • Recently super-flowing concrete has been developed and used in many construction sites in Japan. It is believed that super-flowing concrete will change the construction method and contribute to the durability of concrete structures. In this study the effect of mix proportion on the flowing characteristics of super-flowing concrete was investigated to establish the mix design method. From the result we have found that self-compactability of super-flowing concrete was greatly affected by the unit gravel volume and paste/gravel volume ratio. Therefore the two parameters can be used in mix design of super flowing concrete.

  • PDF

Effect of Initial pH and L-Arginine on the Composition of Fatty Acids of Streptomyces viridochromogenes

  • Oh, Choong Hun;Jung, Sang Oun;Pyee Jae Ho;Kim Jae Heon
    • Journal of Microbiology
    • /
    • v.34 no.4
    • /
    • pp.316-319
    • /
    • 1996
  • Mycelia of Streptomyces viridochromogenes grown under different pH were analysed for the fatty acid composition. The low relative proportion of 12-methyltetradecanoic acid and the high relative proportion of palmitic acid were characteristic for the young culture under slight acidic pH that caused delay of the aerial mycelium formation. The addition of L-arginine to the culture medium enabled an arginine auxotroph with bald phenotype to have the fatty acid composition similar to that of the wild type and to develop aerial mycelium. The ratio of 12-methyltetradecanoic acid to palmitic acid might be used as a parameter to explain the optimum grwoth in the respect of membrane fluidity.

  • PDF