• 한국지반공학회논문집
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• 제19권4호
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• pp.265-275
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• 2003

본 연구에서는 매립지에서 사용되고 있는 토목섬유 (지오멤브레인, 지오텍스타일, 토목섬유 점토 차수재) 사이의 동적 접촉 마찰 특성을 평가하기 위해서 진동대 실험을 실시하였다. 동적 하중하에서 진동대와 하부에 토목섬유가 부착된 상자의 가속도, 이들 사이의 상대적 변위를 측정하였으며, 연직응력, 진동 주파수, 건조/수침 상태가 접촉면의 동적 거동 특성에 미치는 영향도 알아보았다. 실험 결과를 통해 동적하중이 감쇠없이 토목섬유 사이를 통과하는 한계 가속도가 존재함을 확인하였으며, 이를 이용하여 토목섬유 사이의 동적 접촉 마찰각을 산정할 수 있었다. 접촉면에서의 상대 변위는 접촉면의 형태와 건조/수침 상태에 따라 다르게 측정되었다. 각 토목섬유 접촉면에 대한 최대 상대변위는 무차원으로 정규화시켜, 가속도와 최대 미끄러짐 사이의 관계식을 구하였다. 이 식을 이용하면 주어진 가속도와 주파수에서, 토목섬유 사이를 따라 발생되는 최대 미끄러짐의 크기를 예측할 수 있다.

• 한국실내디자인학회논문집
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• 제41호
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• pp.121-128
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• 2003

This study was purposed to find that the elderly in Daejeon city evaluated design details in bathroom, stairway, entrance etc. On the base of housing expenses and an administrative district, the elderly over 65 were chosen and interviewed by well-trained investigators and 583 case was analyzed through SPSS PC 10.0. The results of this study were as follows ; they said a bathtub was necessary, the floor was not slippery, the height of basin was not high and the grab bar around toilet was not in bathroom and emergency bell was not in house. The elderly pointed out that the non-slip floor, grab bar, bathtub in bathroom and non-slip floor in entrance and stairs should be designed carefully. By the condition of the elderly' health and independent daily living and experience of housing, the evaluation of importance on bathroom and approach design by the elderly were different.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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• pp.143-147
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• 1992

Description of the behavior of the R.C structural members fixed on massive concrete is not normally generalization of recognized configuration for regular R.C. design guidanes. This can be due to the complexity of evaluation of internal resistancy and deflection changes of the members subjected to the various external forces. On the base of axially loaded member fixed on footing, however, the estimation of deflection changes due to flexural force shear force and rotational force is to be carried out in ways of specifying the bond characteristics of axial bars embedded in massive concrete. This work is to quantify adhesion of steel-concrete, initial concrete cracking stress near bar rib, maximum bond stress and residual stress in concrete respectively. In addition to quantification of them for particulate behavior, the suggestions of multi-linear bond stress-slip diagram made in carrying out finite element analyses for adhesion failure, examining concrete cracking status and reviewing existing experimental data lead to alternatively constructed relationship between bond stress and slip for a axial bars embedded massive concrete.

• Structural Engineering and Mechanics
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• 제83권1호
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• pp.109-121
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• 2022

Twelve push-out test specimens were conducted with various parameters to study the static and fatigue performance of a new through-bolt shear connector transferring the shear forces of interface between prefabricated hybrid fiber reinforced concrete (HFRC) slabs and steel girders. It was found that the fibers could improve the fatigue life, capacity and initial stiffness of through-bolt shear connector. While the bolt-hole clearance reduced, the initial stiffness, capacity and slippage of through-bolt shear connector increased. After the steel-concrete interface properties were improved, the initial stiffness increased, and the capacity and slippage reduced. Base on the test results, the equation of the load-slip curve and capacity of through-bolt shear connector with prefabricated HFRC slab were obtained by the regression of test results, and the allowable range of shear force under fatigue load was recommended, which could provide the reference in the design of through-bolt shear connector with prefabricated HFRC slabs.

• 한국전산구조공학회논문집
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• 제22권1호
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• pp.105-115
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• 2009

휨거동을 하는 전단벽을 대상으로 동일한 총 단면적을 갖는 1개의 전단벽과 마찰형 감쇠기로 연결된 전단벽의 내진성능을 수치해석을 통해 비교하였다. KBC 2005 설계스펙트럼을 근거로 축소 조절한 7개의 지진파를 입력하중으로 마찰형 감쇠기가 설치된 전단벽의 평균응답을 분석하였다. 마찰형 감쇠기의 중요한 설계변수인 기준 마찰력인 슬립하중은 각층의 마찰형 감쇠기 위치에 생기는 수직방향 전단력의 총합의 5, 10, 20, 30, 60, 90%값으로 하여 슬립이 특정한 층에 편중되지 않도록 하였다. SeismoSturct 프로그램을 이용해 비선형시간이력 해석을 수행하여 밑면 전단력, 에너지 소산량, 1층 벽체곡률, 최상층변위 측면에서 마찰 감쇠기의 제진성능을 분석하였다. 기준마찰력의 30%이하 수준의 총 마찰력을 갖는 마찰 감쇠기가 우수한 제진성능을 보였다.

• 한국농공학회논문집
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• 제61권3호
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• pp.23-30
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• 2019

In this study, we evaluated the applicability of proper embedded depth of fillings by examining the uplift resistance using spiral foundation and top base foundation. As a result of the model test, the maximum uplift resistance increased with the embedded depth. The maximum uplift resistance of each region was found to be 50cm depth. The spiral foundation was 335.14N of Sancheong, 312.32N of Seongju, 403.94N of Wanju, and the top base foundation was 745.06N of Sancheong, 1028.82N of Seongju and 950.76N of Wanju. The yield point after the elastic section in the stress-displacement graph of the top base foundation was calculated as the maximum uplift resistance. For this reason, farmers do not actually use top bases foundation. Therefore, it was considered that the additional load increase due to slip connector will not occur. Model test results show that the maximum uplift resistance increases with the purlinss installed under the ground. Therefore, additional comparative studies through purlins installation will be needed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.302-309
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• 2008

This paper presents a vector control of Linear Induction Motor base on a slip frequency control. And a linear induction motor modeling included the end effect using circuit and equation method is also proposed. We demonstrated through simulation the improvements achieved by the proposed scheme.

• Nuclear Engineering and Technology
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• 제45권4호
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• pp.505-512
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• 2013

Three types of zirconium base alloy were evaluated to study how their work hardening behavior is affected by alloy composition. Repeated-tensile tests (5% elongation at each test) were performed at room temperature at a strain rate of $1.7{\times}10^{-3}s^{-1}$ for the alloys, which were initially controlled for their microstructure and texture. After considering the yield strength and work hardening exponent (n) variations, it was found that the work hardening behavior of the zirconium base alloys was affected more by the Nb content than the Sn content. The facture mode during the repeated tensile test was followed by the slip deformation of the zirconium structure from the texture and microstructural analysis.

• 국제강구조저널
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• 제18권4호
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• pp.1373-1383
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• 2018

Experimental study was conducted to investigate the seismic behavior of roof joint. Eight full-scale specimens were tested considering the effects of axial force, joint height, hole shape of base plate and edge distance of concrete on the failure mode and resistance capacity of roof joint. With the increase of axial force, the hysteretic curves were fuller. The mechanical model of roof joint change from bending to shear. With the increase of joint height, the ultimate strength of roof joint decreased. If the hole shape of base plate changed from circle to loose, the slip behavior of roof joint appeared and the ultimate strength of roof joint decreased. The damage of edge concrete may occur if the edge distance of concrete was not big enough.

• 한국도로학회논문집
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• 제12권4호
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• pp.197-202
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• 2010

차선을 벗어난 승용차가 기초에 강결된 표지판 지주에 충돌할 경우 차량이 받는 충격과 변형은 탑승자의 안전을 위협하게 되므로 분리지주를 쓰는 것이 일반적이다. 국도에서 $1200mm{\times}1200mm$의 단일노선표지에 사용되는 직경 101.6mm, 두께 4.0mm의 강관지주가 기초에 강결되었을 때와 Clip형 분리장치를 갖는 경우에 대한 820kg-50kg-정면 충돌 시 차량과 지주의 거동을 LS-DYNA 시뮬레이션을 통하여 비교 분석하였다. 분리식 지주 충돌 시뮬레이션 결과는 동일한 조건의 충돌실험 결과와 비교하여 신뢰도를 높였다. 강결된 원형지주에 대한 충돌 시뮬레이션 결과 탑승자 안전지수(THIV, PHD)와 차량의 변위가 탑승자의 안전을 위협하는 수준으로 나타났으나 Clip형 분리장치를 갖는 지주에 대한 충돌 시뮬레이션 결과 충돌 시 지주의 분리로 감속도가 현저히 줄어들어 안전한 것으로 확인되었다.