• Title/Summary/Keyword: Static Test

Search Result 3,282, Processing Time 0.028 seconds

Elevated Temperature Static Fatigue in Silicon Nitride (질화규소의 고온정피로거동)

  • Choi, Guen;Choi, Bae-Ho;Kim, Ki-Yong
    • Journal of the Korean Ceramic Society
    • /
    • v.36 no.1
    • /
    • pp.15-20
    • /
    • 1999
  • Elevated temperature static fatigue behavior of silicon has been investigated by stress intensity/life test method. Static fatigue crack growth rate increase with the increase of temperature. Such tendency is found to be mainly related to the decrease of fracture toughness with the increase of temperature. That is, when static fatigue crack growth rate, da/dt is expressed by da/dt=AK1m, a constant A is a function of fracture toughness Kc and the exponent m is a constant which is independent of temperature or Kc. However, in the case of high temperature that glass phase is softened, the crack growth rate is found to be deviated from the above relation. This reason is, thus, discussed.

  • PDF

EMS Application Effect of Lower Extremities to Improve Static Balance Capability (정적 균형능력 향상을 위한 하지 의류의 EMS 적용 효과)

  • Hwang, Sunkyu;Park, Jinhee;Kim, Jooyong
    • Journal of Fashion Business
    • /
    • v.25 no.4
    • /
    • pp.151-160
    • /
    • 2021
  • The purpose of this study was to investigate whether there were improvements on balance when both ankle-jointed calf muscles and hip muscles, which affect balance capabilities, were activated through taping techniques and EMS. In this study, the One Leg Standing Test, a static balance test, was conducted by experimenting on a flat floor, foam pad, and a stretching board with a gradient of 20 degrees, respectively, to study static balance capabilities in different situations. Nine healthy men in their 20s were measured five times every five minutes considering muscle fatigue, and the difference between each variable was analyzed through post-test using nonparametric statistical analysis. Our results showed an equal increase in static balance capability was similar when EMS was applied only to calf muscles and only to hip muscles. Notably most improvements were seen when wearing calf supporters and taping technology pants, and applying EMS together. It was also found that the difference between EMS electric stimulation and balance capability was greater when wearing and applying supporters and taping technology pants. Based on the results of the present study, a muscle support band and EMS of taping techniques can improve balance capabilities. These findings are expected to form a basis for solutions Improving the balance capabilities

A Laborratory Study of the Fatigue and Development of Analysis Program of Concrete Pavements (시멘트 콘크리트 포장의 피로실험과 프로그램 작성)

  • 엄주용;임승욱;윤기용
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1996.04a
    • /
    • pp.232-240
    • /
    • 1996
  • In the present study, a series of static load test and fatigue test were carried out to investigate the behavior of the CRCP. The specimens were sized to 25% of real one lane CRCP. The fatigue tests were carried out for the repetitive load as much as 16%, 39%, 40%, 48%, 59% and 78% of the max. static load for the center or corner loading. Compared the field test with laboratory test for FWD, it is an equpment useful to maintance and manage of the concrete pavements.

  • PDF

A Comparative Study on Liquid Limit Value (시험방법에 따른 액성한계치의 비교 연구)

  • 장정욱;박춘식;하주화
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2003.03a
    • /
    • pp.375-382
    • /
    • 2003
  • This study, Using Pusan clay, examined a relationship between Dynamic and Static Liquid Tests. The Static Liquid Tests wow carried out based on BS and JIS. The results of the study are summarized as follows. (1) The result of the Dynamic Liquid Limit Test showed that the liquid limit values of air-dried soil were greater than those of oven-dried soil by 4%~15% (2) The liquid limit value of the Static Liquid Limit Test was greater than that of the Dynamic Liquid Limit Test by 2%~9%. The following equations show the relationship between the two values WL,Fall(JIS) = 0.961ㆍWL,Cas. + 4.209 WL,Fall(BS) = 0.969ㆍWL,Cas + 5.024 (3) The liquid limit value of BS was greater than that of JIS by 1%~6%. The following equation shows the relationship between the two values.

  • PDF

The Effect of Trunk Stability Exercise on Balance and Gait in Stroke Patients (체간 안정화 운동이 뇌졸중 환자의 균형과 보행에 미치는 영향)

  • Song, Ju-Min;Kim, Soo-Min
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.5 no.3
    • /
    • pp.413-420
    • /
    • 2010
  • Purpose : The purpose of this study was to demonstrate the effect of trunk stability exercise on various support base and posture on gait speed, static and dynamic balance performance. Methods : Included 17 persons with stroke who were living in the community. Trunk stability exercise program was conducted three times per week, 50 minutes per session, for 8 consecutive weeks. Subjects were tested with 10 m walking test(sec), multidirectional reach test (cm), timed get up and go test(sec) and K.A.T.3000 at both (pre and post treatment) time points. Paired t-test was used to exam mean differences between pre and post treatment by using SPSS 12.0. Results : After 8 weeks exercise program, there were significant differences in gait speed, static and dynamic balance performance(p<0.05). Conclusion : This study have shown that trunk stability exercise on various support base and posture improve physical functions(gait speed, static and dynamic balance performance).

A Study on Residual Strength of Damaged Sandwich Composite Structure (샌드위치 복합재 구조의 손상에 의한 잔류 강도 연구)

  • Kong, Chang-Duk;Kong, Hyun-Bum;Kim, Sang-Hoon;Song, Min-Su
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.2073-2079
    • /
    • 2008
  • This study aims to investigate the residual strength of sandwich composites with Al honeycomb core and carbon fiber face sheets after the quasi-static indentation damage by the experimental investigation. The 3-point bending test and the edge-wise compressive strength test were used to find the mechanical properties. The quasi-static point load and damaged hole was applied to introduce the simulated damage on the Each damaged specimens were finally assessed by the 3-point bending test and the compressive strength test. The investigation results revealed the residual strength of the damaged specimens due to the quasi-static indentation.

  • PDF

A Study on the Shear Strength Properties of Reinforced Concrete Beams according to Shear Span-Depth Ratio (전단지간비에 따른 철근콘크리트 보의 전단강도특성에 관한 연구)

  • Park, Jong-Gun
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.4 no.1
    • /
    • pp.93-100
    • /
    • 2000
  • The purpose of this study is to investigate the shear behavior of reinforced concrete beams according to small shear span-depth ratio between a/d=1.5, 2.8, 3.6. In general, shear strength of reinforced concrete beams is dependent on the compressive strength of concrete the longitudinal steel ratio, the shear span-depth ratio and shear reinforcement. The static test was carried out to measure the ultimate load, the initial load of flexural and diagonal cracking, crack patterns, fracture modes. The load versus strain and load versus deflection relations were obtained from the static test. The test results on shear strength were compared with results obtained by the formulas of ACI code 318-95. The shear strength of reinforced concrete beams exceeded those predicted following present ACI code 318-95(11-6).

  • PDF

A Study on The Load Test Method and Result For Bogie Frame of New LRT (신형 경전철차량 대차프레임 하중시험 방법 및 결과 고찰)

  • Kim, Weon-Kyong;Won, Si-Tae;Jeon, Chang-Seong
    • Proceedings of the KSR Conference
    • /
    • 2008.11b
    • /
    • pp.1679-1688
    • /
    • 2008
  • Recently, the bogie frame weight of Light Rail Transit system has been reduced in order to save energy and materials. However, this light weighted vehicle structure is very important to verify the fatigue strength at the development stage. Bogie system consists of bogie frame, suspensions, wheel-sets, braking system and transmission system. Among these components, the bogie frame is most significant component subjected to the whole vehicle and passenger loads. In this study, the bogie frame for the New LRT power car is evaluated to the static and fatigue strength. And the evaluation method is used the LRT Performance Test Standards Specification throughout the FEM analysis and static load test. The static and fatigue test results for the LRT bogie frame of power car has been appeared very safety and stable for the design load conditions.

  • PDF