전문대학(專門大學)의 교육(敎育)과 산업계(産業界) 인식(認識)

유범식 한국농공학회 1990 韓國農工學會誌 : 전원과 자원 Vol.32 No.3

다짐흙의 剪斷强度 異方性에 관한 硏究

劉範植,朴根洙 안성산업대학교 1987 論文集 Vol.19 No.-

The shear strength of compacted cohesive soil and sandy soil to be conducted by dynamic and static compaction testing method have different anisotropy each other. Therefore, it is expected some anisotropy in accordance with mixing proportion of fine grain portion and sand in soils. Samples used in this study was mixed proportion by dry weight to 5 grades of 0%, 20%, 40%, 60% and 80% with Ju Moon Jin standard sand and finer 0.074mm particles in diameter. Dynamic and static compaction test in optimum water content was carried out, and subsequently direct shear test were conducted in unsoaking and soaking conditions on two kinds of specimen which were trimmed vertically and horizontally for compaction direction. The conclusion on testing strength anisotrapy of samples are summarized as following. (1) The shear strength of vertically trimmed specimens in more 60% samples sand content is exhibited greater than that of horizontally trimmed specimens, and in less 60% samples horizontally trimmed shear strength is shown anisotrapy to be greater than verticaly those. From that results it was presented strength anisotropy in more 60% of sand content to be nearly the same as sandy soils, and in less 60% of sand content to be the same as cohesive soils. (2) Unsoaking specimens in statically compacted soils was shown relations to be (^ι_f)v > (^ι_f)_H regardless of sand content, and that proporties are considered which orientation of soil particles make great contribution to strength anisotropy. (3) The shear strength anisotropy in mixing samples is considered to be mainly caused by anisotropy of cohesion. In dynamic compacted sample of more 60% of sand content, the cohesion of V specimens was obtained greater than that of H specimens, and in static compacted sample, cohesion of V specimen is greater than that of H specimens regardless of sand content. (4) Internal friction angle of H and V specimens according to compaction method and sand content is shown little obvious the difference in degrees and anisotropy. (5) The shear strength in dynamic and static compacted samples was greatly decreased on soaking specimens compared with unsoaking specimens, independent of sand content. And anisotropy at H and V specimens. on 0% and 80% of sand content is shown a little, however cohesion in dynamic compacted samples of 60% is disappeared anisotropy. (6) In soaking specimen, cohesion is greatly decreased irrespective of compaction method, and especially cohesion of V and H specimen in 60% sample sand content is fallen to zero. The internal friction angle is shown little obvious influence caused soaking.

흙의 다짐率과 透水性에 關한 試驗

劉範植 안성산업대학교 1976 論文集 Vol.8 No.-

堰堤等 盛土用 흙의 다짐比率 變化에 따른 間隙比, 透水係數 變化에 對하여 본 試驗에서 얻은 結果를 要約하면 다음과 같다. 1. 最適含水比는 細粒子의 含有量이 많을수록 直線的인 增加를 하였다. 2. 다짐比率이 減少됨에따라 間隙化의 增加現狀은 顯著하였으며, 最適含水比가 큰 흙일수록 다짐比率 低下에 따른 間隙化 增加現狀은 緩慢하였다. 3. 細粒土에서는 다짐比率이 緩慢하였고 細粒子 일수록 그 增加比率은 컸다. 4. 最適含水比가 큰 흙일수록 透水係數는 작어지며 最適含水比 20∼25% 以上인 흙에서는 다짐比率에 따른 透水係數 變化가 거의 없었다. 5. 흙의 塑性과 透水係數는 거의 反比例하며 液性限界가 50% 程度이면 透水係數는 비슷하였다. This report is a study on relationship between void ratio, coefficient of permeability and other physical properties of compacted soil in varius compaction ratio. The results of the study can be summaried as follows: 1. The optimum moistrure content of soil, is increase with. increment of fine grading soil, and the relationship is a straight line. 2. The increasing a phenomenon of void ratio is remarkable by the decrease on the compaction ratio in much optimum moisture content. 3. The increase ratio on the coefficient of permeability of soil is slow with decrease of compaction ratio in the fine grading soil. Coarse grading soil is much at the ratio of increase. 4. The coefficient of permeability of soil decrease with increasing of optimum moistrue content. And the permeability of soil is almost constant when optimum moisture content is more than 20 to 25 percent, even though compaction ratios increase. 5. The soil of the plasticity and permeability is almost inversly proportional. The coefficient of permeability is almost constant when the liquid limit is 50 percent.

다짐한 不飽和 粘性土의 剪斷 强度 特性에 관한 硏究

劉範植 안성산업대학교 1992 論文集 Vol.24 No.-

This study carried out to investigate characteristics of compacted unsaturated cohesive soils widely used for construction of fill dam, road, residential and industrual site. It is performed undrained unconsolidation compression test, isotropic triaxial compression test and average principal stress test in constant condition. Testing conditions are ; 1) dry density is constant, variable water content, 2) water content is constant, variable dry density. The results of study are as follows ; 1. The stress conditions in triaxial compression test are considered average principal stress component and purely shear component. 2. The shear stress of soil used in evaluated smaller about 20% in accordance with correction of volumetric strain by shear component. 3. Volumetric change in accordance with average principal stress increment are corrected by time effect only considered, exist doubt on a propriety. 4. The difficult problem in unsaturated soil on theory are remained today, therefore this results are useful for analysis of unsaturated soils behaviour.

粘性土의 一軸壓縮 强度와 그의 實用性에 關한 硏究

劉範植 안성산업대학교 1982 論文集 Vol.14 No.-

一軸壓縮 强度의 測定値로서 粘土와 砂質土의 中間的 粒度組成인 粘性土의 實用的 壓縮强度를 求하기 위하여 粒度를 調整한 試料에 대하여 實施한 一軸壓縮 및 三軸壓縮 試驗 結果를 要約하면 다음과 같다. 1. 粒度組成이 砂質土에 가까운 飽和粘性土는 壓密 終了後 拘束壓의 除去에 따라서 飽和度 및 非排水 剪斷强度가 低下하며 非排水 剪斷强度의 低下比率은 砂質土에 가까울수록 顯著하였다. 2. 砂質土에 가까운 粘性土의 測定, 一軸壓縮 强度는 地盤속에서의 粘着力보다 작으며 拘束壓 除去에 따르는 減少分을 補正할 수 있다. 3. 補正係數는 粘土 含有量 및 塑性指數의 ??數로 取扱하는 것이 可能하다. 4. 粘土 含有量이 10%以下인 흙에 대하여는 適用할 수 없으며 粒度分析 試驗 또는 塑性指數에 대한 試驗을 愼重히 하여야 하겠다. A series of unconsolidated undrained triaxial compression and unconfined compression tests are preformed on soil samples for some range of particle grading by mixing clay portion and sand portion with various proportion, in order to investigate a practical treatment of undrained shear strength of soils of intermediate grading between clay and sand. The results are as follows : 1. As the clay fraction of saturated sample decrease, degree of saturation and unconfined compression strength becomes relatively smaller according to release of confining pressure after consolidation completion. 2. The nearer in sand, decreasing rate of unconfined strength is obvious. 3. Based on the test results, the measured value of unconfined compression strength of soils having intermediate grading between clay and sand can be corrected reduction for stress release in the in-situ soul sampling. 4. This correction requires the overburden stress in term of total stress and two kinds of correction factors, which are determined by the clay fraction and plasticity index. 5. Application of this correction is limited to the soils of clay fraction of more than 10%, and test of grading analysis will be operate circumspectly.

靜的으로 다진 不飽和 點性土의强度와 變形에 대하여

劉範植 안성산업대학교 1980 論文集 Vol.12 No.-

This study was carried out to get result the strength and volumetric strain characteristics for consolidated cohesive soils obtained from Triaxial compression tests. The results are summarized as follows: 1. Volumetric strains depend upon only shear stress compoment were expressed a tendency to be swelling side in scope of 1-2% of Ea, the higher the Ea to be compression side. 2. Separation volumetric strain according to change of isotropic pressure shear strength was decreased when it is corrected. Therefore, shear constants were used on practice ingeneral seems to be large too. Though it had been problems to regard only time effect for correction of volumetric strain in accordance with increment of mean principal stress it was thought to bea way to obtain on bohaviour of unsaturated cohesive soils.

浸水된 다짐흙이 剪斷特性에 關한 硏究

劉範植 안성산업대학교 1984 論文集 Vol.16 No.-

The shear characteristics of soils change generally caused by soaking. The author have performed direct shear test in soaking and unsoaking samples on a silty sand and three clays prepared widely used for banking. The conclusions are summarized as follows: 1) The settlement appearance by soaking in loading is caused by disappearance of compressive force among the particles by capillary water, it is explained with Bishop's effective stress equation of partly saturation. 2) The lower of moisture content of sample, the sattlement showed a tendency to increase when silty sand and non compressive clay is soaked on loading. 3) The shear strength of soils is caused by decrease for lubrication of inter-particles with permeated water. Hense, this fact must be considerated for design of banking structures. 4) According to increment initial moisture in soaking and un-roaking samples, variation of soil structure to take influence of shear strength characteristics didn't appeared. 5) The higher of compressive soils, dilatancy index in soaking samples is lower than it of unsoaking.

흙의 다짐과 物理的 性質에 關한 試驗

劉範植 안성산업대학교 1977 論文集 Vol.9 No.-

This study is to investigate the relationship of compaction and some physical properties in soil. Some results obtained in this study are summarized as follows. 1. Generally, the relationship between maximum dry density of the compacted soil and optimum moisture content. and liguid limit show negative correlation as _rdmax = a + bx (a > o, b < o ). 2. The relationship between optimum moisture content and liguid limit and plastic limit and between liguid limit and plastic limit can be repressented positively linear correlation as Wopt = a + bx (a > o, b > o ). 3. The fact that maximum dry density is decreased with increase of the optimum moisture content and liguid limit of any compacted soil, and fact that optimum moisture content is increased positively with liguid limit and plastic limit, lead to the conclusion that clay content is direct factors in reductuon of the maximum dry density.

세립분 함유율에 따른 투수특성에 관한 실험적 연구

유범식,조성민 안성산업대학교 1995 論文集 Vol.27 No.-

Permeability characteristics are varied with fine grained soil contents, because soil is composed of various grain size. A series of permeability test is performed with the specimens obtained by standard compaction test, and soil samples are obtained by mixing the standard sand with the fine grained soil(passing of #200 sieve) whose rate is from 5% to 50% respectively. The test results are follows. 1) Specmens with 25%-30% fine grained soil shows maximum density but the permeability is not proportional to the density. 2) The relation between dry density and void ratio is derived as following equation. <본문참고> Therefore it is known that here is close relation between dry density and void ratio. 3) The specimens up to 30% fine grained soil, permeability decreases proportional to straight line, but the specimens over 30% fine grained soil, the variation of permeability is almost neglegible. Where as the ralation between permeability and the fine grained soil content is as follows. 30% 〈 log K= -1.492-0.19x 30% 〉log K=-3.89-7.78×10^-2x-3.6×10^-5x^2 (x : fine grained soil cotent ratio) 4) Permeability diminishes on the increment of fine grained soils under the same void ratio on account of it varies with soil grains distribution and related to the size and shape of soil structure.

動力耕운機 利用現況에 관한 調査硏究 : 安城地方을 中心으로 In Ansung district

劉範植 안성산업대학교 1972 論文集 Vol.5 No.-

現在 動力 耕耘機를 主軸으로 하여 推進되고 있는 農業 機械化政策遂行에 있어 考慮할 問題点을 究明하기 위하여 安城地方을 中心으로 動力 耕耘機 利用 農家의 利用實態를 조사分析한 바 다음과 같은 結果를 얻었다. 1. 耕地整理, 農路, 水利施設의 不備로 附帶 作業機가 充分히 利用되지 못하고 있었다. 2. 動力 耕耘機의 機體 및 作業機의 重量이 클수록 運搬 以外의 農作業에는 不便을 招來하며 非能率的이었다. 3. 耕地面積이 狹小한 非 平野 地域에서는 5∼6 P.S.程度의 小馬力의 耕耘機 보급이 現實的이며 營農形態, 規模 및 地域에 따라 適正機種을 選擇할 수 있도록 大,中,小馬力의 耕耘機를 生産補給토록 하여야겠다. 4. 原動機 免許를 同時에 取得할 수 있도록 耕耘機 運用上 必要한 技術과 知識을 向上시켜야 하겠다. 5. 機械 技術敎育은 感受性이 높은 靑少年에게 實施하는것이 效果的이므로 農業系學校 施說확충에 積極支援하여야 하겠다. 6. 耕耘機 附帶作業機는 營農形態에 따라 選擇할 수 있도록 하며 利用時間을 연장하여 所得增大를 도모하기 위한 附作業機(Mower, Protector, roader, plantor, roller, bulldozer, roter etc)를 硏究하여 增加시켜야겠다. 7. Trailer의 구조 및 强度는 Engine의 馬力에 따라 달리하며 더욱 튼튼하게 製作하여 改造에 對한 農民의 부담을 없애도록 하여야겠다. 8. 耕耘機 수리수선 및 附屬品 取給所를 최소한 郡廳所在地에 1個所程度 設置하도록 制度化하여야 할석이다. In order to investigate the status of the utilization of power tiller in Ansung district, the survey was carried out with 20 farms and following results were obtained. 1. Accessary equipments were not utilized efficiently owing to lack of farm reformation, farm road, structure of water-utilization 2. Heavy power tillers assembled with high power engine were used only as the carriers and were very inefficient for the farming purpose. 3. Low P.S. power tillers (5~6 P.S) are moved ideal for the on nonplain area. 4. The training was wanted to be able to get the engine operating license. 5. For the yound future farmers more support were needed for the agricultural schools. 6. The studies on the more suitable accessary equipment which will be met the small scale farming to increase the operation time. 7. The new trailer model which is suitable for the vent and uneven farm road, is wanted to decrease the farmor's monetary burden needed to reform the trailer. 8. In order to make the power tiller manufacture co. establish a ageney for each country, the institution should be made.