미끄럼 방지 제동장치용 솔레노이드 밸브의 모델링에 관한 연구

송창섭,양해정,Song, Chang-Seop,Yang, Hae-Jeong 한국정밀공학회 1995 한국정밀공학회지 Vol.12 No.12

Anti-lock Brake System has been developed to reduce tendency for wheel lock and improve vehicle control during sudden braking on slippery road surfaces. This is achieved by controlling the braking pressure avoiding wheel lock, while retaining handling and brake performance. This paper is concerned about characteristics of a solenoid valve in hydraulic modulator for controlling brake pressure. First, it was modeling the electromagnet by the permeance method. Second, it was modeling the commercial Maxwell poackage program. And then, a experiment was performed in order to justify modeling. The result of modeling coincided with teh result of experiment and commercial packabe program. As a result, these modelings will be able to use in analysis of dynamic character- istics of the solenoid valve for braking.

흙-수분 특성곡선 방정식을 이용한 포화도의 예측

송창섭,Song, Chang-Seob 한국농공학회 2004 한국농공학회논문집 Vol.46 No.6

The aim of the work described in this paper was to confirm the application of the equation of the soil-water characteristic curves on an unsaturated soil. A series of suction test for unsaturated soils was conducted on the selected 4 kinds of soil using modified pressure extractor apparatus. And it was carried out to analyse The experimental parameters which can be describe the soil-water characteristics, were determined by using the data obtained from the experiment. From the results, it was found that The matric suction varied according to the grain size distribution, amount of fine grain particles and void ratio. Also it was found that the residual degree of saturation was decreased with in crease of the void ratio, but the pore size distribution index and air entry value were increased with in crease of the void ratio. And The application of the soil-water characteristic curve equation was confirmed for the various conditions and the various state by the comparison between the measured degree of saturation and the predicted degree of saturation.

농촌용 수로의 유형에 따른 토사 퇴적량 예측

송창섭,임성윤,Song, Chang Seob,Lim, Seong Yoon 한국농공학회 2014 한국농공학회논문집 Vol.56 No.6

Development of the economic methods and the design of the standard sections needs the more project fund and land than ever leads to the objection of enlarging canal arrangement to need economic construction method development and standard design for supporting it. The objective of this study was to evaluate the performance of selected sediment reduction methods to reduce sediment discharges from drain and irrigation of different land types (Mountain, Flatten, Reclaimed land). This study was carried out to analysis for the soil loss and sediment of drain and irrigation by comparing RUSLE method and amount of sediment from amount of dredging data of Korea Rural Corporation. The results of study were analyzed and summarized as follow. Size of soil sediment from the upper region of drain and irrigation of mountains bigger than lower region. But in case of flatten and reclaimed land, size of soil sediment from the upper and lower region of drain and irrigation did not classified. In case of comparison drain and irrigation without classifying of land type, size of soil sediment from irrigation is bigger than drain.

일축압축강도에 의한 선행압밀응력 예측 및 분석

송창섭,김명환,Song, Chang Seob,Kim, Myeong Hwan 한국농공학회 2016 한국농공학회논문집 Vol.58 No.6

This study was to evaluate the feasibility of pre-consolidation pressure distribution characteristic of western and southern coastal region, using correlation of unconfined compressive strength and preceding research equation. Pre-consolidation of western and southern region showed similar trends undrained shear strength and pre-consolidation pressure in proportion to unconfined compressive strength. Predicted results of U.S. NAVY. (1982) equation revealed a small error western 9.7 % and southern 0.4 %. Prediction correlation results of pre-consolidation using unconfined compressive strength revealed an error western 16.8 % and southern 0.7 %. It was reported that less than 20 percent of pre-consolidation pressure prediction result of Casagrande forecasting error. Estimates of pre-consolidation pressure are possible, before the standard consolidation test, because it was reported that less than 20 % of the forecasting errors of Casagrande.

노상토 및 보조기층 재료의 변형특성

송창섭,임성윤,Song, Chang-Seop,Lim, Seong-Yoon 한국농공학회 2010 한국농공학회논문집 Vol.52 No.3

It is very important to select carefully backfill materials and build for the structural integrity of abutment in bridge. In general, backfill materials of unbound crushed stones (SB-1) are used to provide the safety of abutment structure and to reduce differential settlement around abutment that is significantly related with performance of road pavement under working conditions. In this study, to evaluate the compatibility of backfill materials at abutment and to develop the abutment design program, i) basic properties of subgrade soils in Korea, ii) evaluation of deformational characteristics of backfill materials from RC/TS tests, cyclic TX tests and Creep tests were accomplished.

간척지 온실기초 나무말뚝의 인발저항력 예측을 위한 실내모형시험 결과 비교·분석

송창섭,김명환,장웅희,Song, Chang Seob,Kim, Myeong Hwan,Jang, Ung Hee 한국농공학회 2016 한국농공학회논문집 Vol.58 No.2

The object of this paper was to evaulate modified proposed design equation in model test result in order to estimate uplift-resistance of timber pile of reclaimed land greenhouse foundation. Uplift resistance result of model test was increased to according to increased of contact area. Uplift-resistance result of field test tend to lineary increased to according to increased of embedment depth and contact area. Results of field uplift-resistance was evaluate compare with modified proposed design equation results of model test and Effective stress method. As the Effective stress method tend to underestimate, modified proposed design equation results of model test tend to similar type. As the contact area increase, difference between field uplift-resistance results and modified proposed design equation results of model test was considered uplift-speed.

불포화토의 투수특성

송창섭,신창섭,Song, Chang-Seob,Shin, Chang-Seob 한국농공학회 2005 한국농공학회논문집 Vol.47 No.4

In order to analyse the flow problems for an unsaturated soil, it is required to examine closely the characteristics of the coefficient of permeability which is changing with the matric suction. To this ends, a permeability test was conducted on the three samples;granular soil, cohesive soil and silty soil. The specimen was made by pressing the static pressure on the mold filled with soil and the void ratio was controled with the different compaction ratio. And the test was performed by using the modified apparatus of the steady state method which was proposed by flute (1972). The range of matric suction was 0-90 kPa. The measured results for the coefficients of permeability were analysed with the void ratio and the compaction ratio, and it was examined closely the characteristics of the permeability for an unsaturated soil.

보강 혼합토의 역학적 특성(II) -섬유 혼합토-

송창섭,임성윤,Song, Chang Seob,Lim, Seong Yoon 한국환경복원기술학회 2002 한국환경복원기술학회지 Vol.5 No.6

This study has been performed to investigate the physical and mechanical characteristics of compaction, volume change and compressive strength for reinforced soil mixed with polypropylene fiber, and to confirm the reinforcing effects with admixture such as polypropylene fiber. To this end, a series of compaction test and compression test was conducted for clayey soil(CL) and polypropylene fiber reinforced soil. In order to determine proper moisture contents and mixing ratio, pilot test was carried out for natural soil and PFRS(polypropylene fiber reinforced soil). And the mixing ratio of mono-filament fiber and fibrillated polypropylene fiber admixture was 0.1%, 0.3%, 0.5% and 1.0% by the weight of dry soil. From the experimental results, it was found that the optimum moisture contents(OMC) increased with the mixing ratio of fiber, but the maximum dry unit weight and the volume change was decreased with the mixing ratio. It means that the improvement of the workability and the reduction of the weight of embankment was done by the addition of the polypropylene fiber. And, from the compression test results, it was found that the addition of the polypropylene fiber remarkably improved the compressive strength of PFRS. And it was observed in the viewpoint of strength that the fibrillated polypropylene fiber reinforced soil was more effective than the mono-filament polypropylene fiber reinforced soil.

공극비에 따른 불포화토의 흙-수분 특성곡선의 도출

송창섭 ( Song Chang Seob ),류태진 ( Lyu Tae Jin ) 한국농공학회 2004 한국농공학회 학술대회초록집 Vol.2004 No.-

자연상태의 지반은 토립자와 간극으로 지반을 구성되어 있으며, 지하수위의 위치에 따라 포화영역과 불포화영역으로 나누어진다. 불포화영역 지반의 간극 속에는 물과 공기가 존재하는데, 간극을 차지하는 물과 공기의 압력차이에 의하여 모세관 현상과 흡착현상이 발생하며, 이러한 현상으로 불포화영역에는 부(-)의 간극수압을 유발하게 된다. 이 때의 부간극수압은 물을 흡수하려는 능력으로 지반의 유효응력을 증가시키는 역할을 한다. 따라서 포화토에 적용하는 이론을 불포화토영역에 적용하는 것은 여러 측면에서 불합리하다. 본 연구에서는 흙-수분 특성곡선을 연구하기 위하여 우리나라의 전역에 분포하는 각종 흙을 채취한 후, 물리적 특성을 분석하여 흙의 분류가 뚜렷이 구분되는 4 종류의 시료를 선정하였다. 선정된 시료는 공극비를 달리하여 공시체를 제작하고, 이를 개조된 Pressure Plate Apparatus에 적용하여 0.1kPa~1,000kPa의 범위에서 약 10단계로 공기압을 공급하여 수분의 이동량을 측정하였다. 측정된 결과를 바탕으로 각 시료의 함수비, 포화도 및 체적 함수비를 분석하여 수분 특성곡선을 도출하고 이들의 특성을 요약하면 다음과 같다. 1. 흡인력과 함수비로 도시된 특성곡선에서 흡인력의 변화에 따른 함수비의 특성은 조립토의 경우는 낮은 흡인력에서는 명확하게 구분이 되는 반면 높은 흡인력에서는 뚜렷하게 구분이 되지 않았고, 세립토의 경우는 뚜렷한 차이를 보이지 않았다. 2. 흡인력에 따른 포화도 특성은 초기에는 구분이 거의 되지 않지만 건조과정이 진행되면서 그 특성을 나타내게 되어 건조된 시료의 흙-수분 특성곡선을 파악하는데 적용할 수 있다. 3. 흡인력에 따른 특성곡선을 체적 함수비로 나타내면 초기 포화부분뿐만 아니라 건조과정이 진행된 후에도 구분이 명확하게 나타났다. 또한 흡인력의 변화에 따른 체적 함수비의 변화는 조밀한 흙보다 느슨한 흙이 훨씬 큰 범위를 가지게 된다. 4. 또한, 조립토에서는 나타나지 않았던 역전현상이 세립토에서는 나타나게 되었다. 그 중 실트질의 흙은 잔류 함수비 부근에서 역전현상을 보이고, 점토질 흙은 공기함입값(air entry value)부근에서 역전현상을 보였다. The purpose of this paper was to investigate the soil-water characteristic curves for unsaturated soil. To this ends, a series of suction measured test was conducted on the selected 4 kinds of soil which is located in Korea, used the modified pressure plate apparatus. From the test results, the water contents, degree of saturation and volumetric water contents was analyzed with the suction. And was drawn the soil-water characteristic curves was drain from the test results for various factors.

PWM 제어에 의한 솔레노이드-유량제어 방식 ABS의 제동압력 특성

송창섭(Chang-Seop Song),양해정(Hae-Jeong Yang) Korean Society for Precision Engineering 1997 한국정밀공학회지 Vol.14 No.8