• 제목/요약/키워드: cohesion test

검색결과 302건 처리시간 0.025초

가족구성원 1인과 2인의 가족적응력 및 결속력평가척도(FACES III) 응답 이용 시 신뢰도 및 타당도 분석 (Reliability and Validity of FACES III When Applied to One and Two of the Family Members)

  • 김정희;박영숙
    • 대한간호학회지
    • /
    • 제32권5호
    • /
    • pp.599-608
    • /
    • 2002
  • Purpose: The purposes of this study were to test the validity and reliability of FACES III when applied to the only one and two family members, and to use more appropriately in the nursing practice. Method: Data were collected from 105 college students and 105 of their parents in two local nursing colleges. The original questionnaire, which was originally developed by Olson(1989), was modified by based on literature review and analyzed by correlation coefficient, Cronbach's α, Guttmans split coefficients and factor analysis. Result: Cronbach's αof the adaptability and cohesion were .77, .73(Guttmans split coefficient were .76, .71) when applied to the only one family member, and were .81, .77 (Guttmans split coefficient were .81, .77) when applied to two. The Pearson's correlation coefficient of the adaptability and cohesion between two family members were .38, .35. The total-item correlations of the other items except for items 5, 7, 13 were significant. The correlation coefficients between adaptability and cohesion when applied to only one and two were .30, .38(p < .01). When the data was analyzed by principle component analysis and Varimax rotation with the number of factors fixed to two, two factors explained 37.2% of total variance in the case of one member, and 42.2% of total variance in two. Conclusion: These results suggested that the concept and the construction validity of cohesion needed to be more clarified. Also It is required that the reliability and validity of FACES III should be tested in two more family members.

풍화잔적토의 함수비 변화에 따른 전단거동특성 (Shear Behavioral Characteristics of Weathered Residual Soil for the Change Water Content)

  • 유남재;김영길;이종호
    • 산업기술연구
    • /
    • 제17권
    • /
    • pp.119-124
    • /
    • 1997
  • This thesis is an experimental research of shear behavioral characteristics and shear behavioral coefficient of weathered residual soil which is mostly contained in soil of Korea. Using the weathered residual soil from mountain near Kangwon National University, this experimental research were contained the physical properties of sample in term of the basic test method such as specific gravity, plastic and liquid limit, grain-size distribution, density and water content. Experimental results obtained from direct shear test sand triaxial compression tests show that according to step loading, linear strain and linear stress increase continually and angle of internal friction decreases just little according to incresing of water content in case of ignoring the cohesion, and angle of internal friction appears the maximum angle near a optimum moisture content in case of considering the cohesion.

  • PDF

하프 PC판과 후타설콘크리트 접합면의 면내전단강도에 관한 실험적 연구 (An Experimental Study on In-Plane Shear Strength of the Interface between Half PC Plate and Cast-in-Place Concrete Plate)

  • 신동원;고만영;이동우;김용부
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
    • /
    • pp.513-518
    • /
    • 1998
  • In Half Precast Concrete Method, such as composite slab and composite wall, Interface between half PC plate and cast-in-place concrete is occurred. And this interface endure lastly in-plane shear which is occurred by external force. Therefore, test was executed to study in-plane shear strength of interface between half PC plate and cast-in-place concrete. In this test, Experimental parameters are finishing condition of the interface, cohesion of concrete, existence and nonexistence of re-bar truss, and angle and direction of lattice of re-bar truss. Comparing and analyzing experimental results, conclusions are obtained as follows. (1) In-plane shear strength of wide interface in composite plate is more affected by the roughness of interface than re-bar truss. And cohesion of concrete contribute to increasing in-plane shear strength. Therefore it seems that the interface should be roughen and kept clean to improve in-plane shear strength. (2) It seems that shear friction equation in ACI code can be sagely available for design of in-plane shear of composite plate.

  • PDF

Bond Analysis of Ribbed Reinforcing Bars

  • Park, Oan-Chul
    • KCI Concrete Journal
    • /
    • 제13권2호
    • /
    • pp.19-25
    • /
    • 2001
  • A simple expression to predict bond strength of reinforcing bars with rib deformation to the surrounding is derived for the case of splitting bond failure. Finite element analysis is used to model the confining behavior of concrete cover. The roles of the interfacial properties, specifically, the friction coefficient, cohesion, the relative rib area and the rib face angle are examined. Values of bond strength obtained using the analytical model are in good agreement with the bond test results from the previous studies. The analytical model provides insight into interfacial bond mechanisms and the effects of the key variables on the bond strength of deformed bars to concrete. Based on the comparison between the analytical results and the test results, the values of cohesion, coefficient of friction, and the effective rib face angle are proposed.

  • PDF

가족 기능성과 대인관계 성향과의 관계 - 경기남부지역 고등학생을 중심으로 - (The Relations between the Family Functioning and Interpersonal Relation Disposition - Focused High School Students in Gyeonggi South Area -)

  • 최규련
    • 한국지역사회생활과학회지
    • /
    • 제15권2호
    • /
    • pp.123-135
    • /
    • 2004
  • The purpose of this study was to examine the relations between family functioning and the interpersonal relation disposition of high school students in southern Gyeonggi province. The subjects of this study were 360 high school students. The scale of family functioning was measured using the Family Adaptability Cohesion Evaluation Scale(FACES Ⅲ) developed by Olson, et al.(1985). To measure the interpersonal relation disposition, Ahn's Interpersonal Relation Disposition Scale(IRDS) was used. The data was analyzed by using t-test, ANOVA, and multiple comparison(Duncan test). The major findings were as follows: There were significant differences in student's family functioning and interpersonal relation disposition according to school department and family economy level. There were significant differences in the interpersonal relation disposition according to gender. Where family functioning was higher, the students' interpersonal relation dispositions were more sympathetic, accepting and socially friendly, while being less rebellious and distrustful. As a result of this study, it is found that family functioning has effects on high school students' interpersonal relation disposition.

  • PDF

유류로 오염된 점성토의 지반공학적 특성 분석 (Geotechnical Characteristics Analysis of Oil Contaminated Clayey Soil)

  • 권무남;김현기
    • 한국농공학회논문집
    • /
    • 제47권1호
    • /
    • pp.43-50
    • /
    • 2005
  • This test was performed to evaluate the change of the unconfined compressive strength, strength parame¡?ters which resulted from direct shear test and oil residue percents analyzed by GC-MS as time lapse, oil addition. Unconfined compression strength of $10\%$ kerosene added by weight of dry soil recovered as time passed. In the case of $5\%$ kerosene added, the strength recovered as much as clean clayey soil after about 50 days passing. For the case of diesel added, the recovery of unconfined compressive strength was not shown even though about 60 days passed. The strength parameters (c, $\psi$) of kerosene added not changed but for diesel added, the cohesion was very decreased as diesel addition increased. Residual percent of kerosene in the soil was less than that of diesel as time passed.

충전절리면의 미끄러짐특성에 관한 연구 (A Study on the Sliding Characteristics of Infilling-joint Surface)

  • 이정엽;박영목;김재석;구호본;백용
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2003년도 봄 학술발표회 논문집
    • /
    • pp.499-502
    • /
    • 2003
  • The purpose of this study is to understand the sliding characteristics of the infilling-joint surface using the new devised shear test apparatus with changeable slope for the original infilling materials and the infilling materials experienced cyclic freezing-thawing processes. Three types of the mother rock classified as the igneous rock, the metamorphic rock and the sedimentary rock and the infilling materials were collected for laboratory test. The cohesion according to the slope change of the rock joint shows large variation within ${\pm}$5 degrees but the internal friction angle shows appears the linear decreasing tendency. It is confirmed that the affecting factor of slope change of rock joint at the behavior of rock mass is larger than that of the infilling thickness. Test results show that the cohesion and the internal friction angle in 100 times of cyclic freezing-thawing processes are decreased about 50 percent compared with original one. A further study using various infillings materials would lead to a better understanding of the failure mechanism of rock mass by slope change of rock joint.

  • PDF

최신 화상 재료의 소개 -마이크로 캡슐 토너- (Introduction of the Advanced Imaging Materials -Micro-encapsulating Treatment of Toner-)

  • 이용규;정경모;코세키 켄이치
    • 펄프종이기술
    • /
    • 제44권6호
    • /
    • pp.79-86
    • /
    • 2012
  • The aim of this general remarks is to introduce the results concerning the thermo physical, charging, developing and fusing characteristics of micro-encapsulated (MC) model toners in order to apply to the toner of electrophotographic system at the condition of a low temperature. In order to clarify the fusing mechanism of MC toner, rheological analysis of the toner was chosen. It was suggested that MC toner had a different fusing mechanism compared with non-MC toner. Some kinds of MC model toners showed a good result on adhesion test as well as cohesion test. Also, it was possible to get the good charging and development characteristic of MC toner for printing test with laser printer.

Mechanism of shear strength deterioration of loess during freeze-thaw cycling

  • Xu, Jian;Wang, Zhangquan;Ren, Jianwei;Yuan, Jun
    • Geomechanics and Engineering
    • /
    • 제14권4호
    • /
    • pp.307-314
    • /
    • 2018
  • Strength of loess that experienced cyclic freeze and thaw is of great significance for evaluating stability of slopes and foundations in loess regions. This paper takes the frequently encountered loess in the Northwestern China as the study object and carried out three kinds of laboratory tests including freeze-thaw test, direct shear test and SEM test to investigate the strength behaviors of loess after cyclic freeze and thaw, and the correlation with meso-level changes in soil structure. Results show that for loess specimens at four dry densities, the cohesion decreases with freeze-thaw cycles until a residual value is reached and thus an exponential equation is proposed. Besides, little change in the angle of internal friction was observed as freeze-thaw proceeds. This may depend on the varying of soil structure, based on which a clue can be found from the surface morphology and mesoscopic scanning of loess specimens. Clearly we observed significant changes in surface morphology of loess and it tends to aggravate at higher water contents or more cycles of freeze and thaw. Moreover, freeze-thaw cycling leads to obvious changes in the meso-structure of loess including lowering the particle aggregates and increasing both the proportion of fine particles and porosity area ratio. A damage variable dependent on the ratio of porosity area is introduced based on the continuum damage mechanics and its correlation with cohesion is discussed.

Mechanical properties of expanded polystyrene beads stabilized lightweight soil

  • Li, Mingdong;Wen, Kejun;Li, Lin;Tian, Anguo
    • Geomechanics and Engineering
    • /
    • 제13권3호
    • /
    • pp.459-474
    • /
    • 2017
  • To investigate the mechanical properties of Expanded Polystyrene (EPS) Beads Stabilized Lightweight Soil (EBSLS), Laboratory studies were conducted. Totally 20 sets of specimens according to the complete test design were prepared and tested with unconfined compressive test and consolidated drained triaxial test. Results showed that dry density of EBSLS ($0.67-1.62g/cm^3$) decreases dramatically with the increase of EPS beads volumetric content, while increase slightly with the increase of cement content. Unconfined compressive strength (10-2580 kPa) increases dramatically in parabolic relationship with the increase of cement content, while decreases with the increase of EPS beads volumetric content in hyperbolic relationship. Cohesion (31.1-257.5 kPa) increases with the increase of cement content because it is mainly caused by the bonding function of hydration products of cement. The more EPS beads volumetric content is, the less dramatically the increase is, which is a result of the cohesion between hydration products of cement and EPS beads is less than that between hydration products of cement and sand particles. Friction angle ($14.92-47.42^{\circ}$) decreases with the increase of EPS beads volumetric content, which is caused by the smoother surfaces of EPS beads than sand grains. The stress strain curves of EBSLS tend to be more softening with the increase of EPS beads content or the decrease of cement content. The shear contraction of EBSLS increases with the increase of $c_e$ or the decrease of $c_c$. The results provided quantitative relationships between physico-mechanical properties of EBSLS and material proportion, and design process for engineering application of EBSLS.