• Title/Summary/Keyword: bedding orientation

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Engineering Properties of Some Sedimentary Rocks from the Gyeongsang Supergroup (경상계(慶尙系) 퇴적암(堆積岩)의 공학적(工學的) 성질(性質)에 관(關)한 연구(硏究))

  • So, Chil-Sup;Choi, Byoung-Ryol
    • Economic and Environmental Geology
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    • v.8 no.4
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    • pp.203-210
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    • 1975
  • The engineering properties of some Gyeongsang sedimentary rocks with respect to the grain size and the orientation of bedding planes were studied. The suitability of the rocks for civil and architectural construction was also investigated. The porosity of the rocks increases in proportion to the grain size. The ratio of the strain due to stress perpendicular to the bedding planes to the strain resulting from stress parallel to the bedding planes increases as the grain size decreases. The study indicates however, that the ratio of Young's modulus due to stress perpendicular to the bedding planes to Young's modulus resulting from stress parallel to the bedding planes increases in proportion to the grain size. The compressive strength of the sandstones studied is much greater than the strength of the conglomerate or shale. Only the coarse grained sandstone can be used for civil and architectural construction, regardless of the orientation of bedding planes. The relationships between compressive strength and density, elasticity and porosity, and compressive strength and mineral content were also studied.

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Simulation of the tensile behaviour of layered anisotropy rocks consisting internal notch

  • Sarfarazi, Vahab;Haeri, Hadi;Ebneabbasi, P.;Bagheri, Kourosh
    • Structural Engineering and Mechanics
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    • v.69 no.1
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    • pp.51-67
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    • 2019
  • In this paper, the anisotropy of tensile behaviours of layered rocks consisting internal notch has been investigated using particle flow code. For this purpose, firstly calibration of PFC2D was performed using Brazilian tensile strength. Secondly Brazilian test models consisting bedding layer was simulated numerically. Thickness of layers was 10 mm and layered angularity was $90^{\circ}$, $75^{\circ}$, $60^{\circ}$, $45^{\circ}$, $30^{\circ}$, $15^{\circ}$ and $0^{\circ}$. The strength of bedding interface was too high. Each model was consisted of one internal notch. Notch length is 1 cm, 2 cm and 4 cm and notch angularities are $60^{\circ}$, $45^{\circ}$, $30^{\circ}$, $15^{\circ}$ and $0^{\circ}$. Totally, 90 model were tested. The results show that failure pattern was affected by notch orientation and notch length. It's to be noted that layer angle has not any effect on the failure pattern. Also, Brazilian tensile strength is affected by notch orientation and notch length.

Development of a Robotic Transplanter for Bedding Plants(II) - Transplantiing Gripper - (육묘용 로봇 이식기의 개발(II) - 이식 그리퍼 -)

  • 류관희;김기영;이희환;박정인
    • Journal of Biosystems Engineering
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    • v.22 no.3
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    • pp.325-332
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    • 1997
  • The use of a robotic transplanter reduces the labor requirement in the greenhouse by carrying out repetitive tasks in an accurate and reliable manner. The transplanter manipulates seedlings by means of end-effector. The end-effector is designed differently from an industrial robot because it manulates biological seedlings of variable size, shape, position, and orientation. This study was conducted to develop an end-effector of a robotic transplanter for bedding plants. The development of an end-effector included selection of the best finger type for the transplanting operation. The performance of developed end-effector was tested and compared with two different transplanting schemes depending on the leaf-orientation consideration. The end-effector developed in this research reliably handled seedlings during transplanting task. Results showed that the shovel type finger was suitable for transplanting with the damaging seedlings.

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Weighted Analysis Method for Estimating the Orientation of Limestone Caves in Korea (가중치를 이용한 국내 석회동굴 발달 방향성 해석법 개발에 관한 연구)

  • Lee, Sang-Kyun;Park, Hyeong-Dong
    • The Journal of Engineering Geology
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    • v.24 no.1
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    • pp.39-52
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    • 2014
  • Limestone caves that consist of main passages and branches are formed by a variety of processes, and have the characteristic of developing with a preferred orientation controlled by discontinuities such as bedding, joints, and faults around the cave. However, it is difficult to analyze a representative orientation from various orientations. To interpret the overall development orientation of limestone caves, this study proposes new development orientation analysis methods, termed the Average Span Ratio Method (ASRM) and the Individual Development Ratio Method (IDRM), using the weighting of persistence. Nine limestone caves in Korea were randomly selected for testing the new methods. The methods show a stronger development orientation for limestone caves than that obtained by traditional methods, which consider only the distribution of development orientations. Based on an analysis of the relationship between the average span and the dip angle of bedding, it is confirmed that shallowly dipping bedding is a major contributor to the expansion of span in limestone caves. In addition, using scan-line survey data acquired in the field, we perform an RMR analysis of stability of the ground around limestone caves.

Development of a Robotic Transplanter for Bedding Plants(III)-Development of a Robotic Transplanter (육묘용 로봇 이식기의 개발(III)-로봇이식기의 개발-)

  • 류관희;이희환;김기영;한재성
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1997.06c
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    • pp.238-246
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    • 1997
  • This study was conducted to develop a robotic transplanter for bedding plants. The robotic transplanter consisted of machine vision system, a manipulator, a gripper and plug tray transfer system. The performance of the robotic transplanter was tested and compared by two different transplanting methods, which were to consider the leaf orientation of seedlings and not to. Results of this study were as follows. (1) A cartesian coordinate manipulator for a robotic transplanter with 3 degree of freedom was constructed. The accuracy of position control was $\pm$1 mm. (2) The robotic transplanter with the machine vision system, the manipulator, the gripper and the transfer system was developed and tested with a shovel-type finger. Without considering the orientation of leaves, the success rates of transplanting healthy cucumber seedlings in 72-cell and 128-cell plug-trays were 95.5% and 94.5% respectively. Considering the orientation of leaves, the success rates of transplanting healthy cucumber seedling in 72-cell and 128-cell plug-trays were 96.0% and 95.0% respectively.

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Development of a Robotic Transplanter Using Machine Vision for Bedding Plants (기계시각을 이용한 육묘용 로봇 이식기의 개발)

  • 류관희;김기영;이희환;한재성;황호준
    • Journal of Bio-Environment Control
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    • v.6 no.1
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    • pp.55-65
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    • 1997
  • This study was conducted to develop a robotic transplanter for bedding plants. The robotic transplanter consisted of machine vision system, manipulator attached with the specially designed gripper, and plug tray transfer system. Results of this study were as follows. 1. A machine vision system for a robotic transplanter was developed. The success rates of detecting empty cells and bad seedlings in 72-cell and 128-cell plug-trays for cucumber seedlings were 98.8% and 94.9% respectively. The success rates of identifying leaf orientation for 72- cell and 128-cell plug-trays were 93.5% and 91.0%, respectively. 2. A cartesian coordinate manipulator for a robotic transplanter with 3 degrees of freedom was constructed. The accuracy of position control was $\pm$ 1mm. 3. The robotic transplanter was tested with a shovel-type finger. Without considering leaf orientation, the success rates of transplanting healthy cucumber seedlings for 72-cell and 128-cell plug-trays were 95.5% and 94.5%, respectively. Considering leaf orientation, the success rates of transplanting healthy cucumber seedling in 72-cell and 128-cell plug-trays were 96.0% and 95.0%, respectively.

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A Simple Vector Calculation Method for the True Failt Displacement Distance (백터계산을 이용한 단층의 이동량 산출법)

  • 황상기
    • Economic and Environmental Geology
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    • v.32 no.4
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    • pp.365-371
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    • 1999
  • Ture diplacement of a fault monement is calculated from the displacement of the index plane such as bedding on an outcrop surface. The input parameters are the orientations of the index, fault, and outcrop planes. It is also necessary to input the orientation of fault striation and the offset distance of the index plane on the outcrop surface. The distances of the total, strike, horizontal and dip slip components of the fault movement are calculated from the input parameters. Hwang(1998) conducted a simlar calculation using trigonoment method. To apply the previous method, the offset distance of the index plane must be measured on a vertical outcrop surface. The calculation method of this study accepts the offset distence of index plane on an outcrop plane of any orientation. Calculation results from both method are indentical, regardless of the simplicity of the new method.

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Development of a Mechanical Crack Model to Analyze Deformation and Failure Mechanism of Rock (암석의 변형 및 파괴거동의 해석을 위한 균열모형 개발에 관한 연구)

    • Tunnel and Underground Space
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    • v.8 no.2
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    • pp.96-106
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    • 1998
  • Rock contains discontinuities at all scales. These discontinuities make rock behave in a complex way. This paper discusses a new approach to underground design based on the theory of rock fracture mechanics. The mechanism of deformation and failure of coal was studied by observing the distributions of length, orientation and spacing of the pre-existing as well as stress-induced cracks. Different types of crack information. The crack information is dependent on the scale used. The cracks propagate along the intersections of the pre-existing cracks, and both extensile and shear crack growth occur depending on the direction of the load relative to the bedding planes. An analytical model that takes into account both shear and extensile crack growth was developed to predict the nonlinear stress-strain behavior of coal including strain-hardening and strain-softening.

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Effects of Geological Structures on Slope Stability : An Example from the Northwestern Part of Daegu, Korea (퇴적암 내의 지질구조가 비탈면 안정성에 미치는 영향 : 대구 북서부 지역의 예)

  • Ko, Kyoung-Tae;Choi, Jin-Hyuck;Kim, Young-Seog
    • The Journal of Engineering Geology
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    • v.22 no.1
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    • pp.1-13
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    • 2012
  • The purpose of this work is to gain a better understanding of the interrelationships between geological structures and slope failure in sedimentary rocks. In the studied slopes, construction-related slope failure could only be observed on the south-dipping slopes. This indicates that slope stability may be dependent on the angular relationships between the dip direction of bedding and the orientation of the slope. Slope failure continued, post-construction, around large fault zones in the studied outcrop; these fault damage zones are, however, not easily recognized in the field. Here we suggest a new method that uses accumulated fracture density to precisely identify fault damage zones. Multiple-faced slopes are now increasingly being exposed during large-scale construction projects in South Korea. This multiple-faced slope analysis indicates that the stability of a slope should be evaluated by identifying domains, through the analysis of possible slopes and their angular relationships with bedding and other discontinuities, prior to construction. Therefore, careful consideration of geological structures such as bedding and other discontinuities, and their angular relationships during the design of cuttings through sedimentary rocks, will increase the efficiency of construction and enable the safe construction of more stable slopes that will retain their stability after construction.

Effect of Pen Floor Condition Depending upon Housing Orientation on the PerFormance of Finishing Hanwoo Steers (우사의 향방에 따른 사육장 바닥면의 조건이 비육말기 거세한우의 생산성에 미치는 영향)

  • 김동균;정다운
    • Journal of Animal Environmental Science
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    • v.10 no.1
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    • pp.37-46
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    • 2004
  • In order to investigate the effect of floor condition on the fattening performance of cattle, sixteen finishing Hanwoo steers of weighting 570kg were fed for 16 weeks to slaughter on two types of sawdust bedding pen oriented to the south(SP) and the north(NP) then obtained following results. The floor condition of SP roofed by transparent material was dry and flat during overall experimental period, whereas, that of NP roofed by solid slate was muddy and rough even in summer and fall, and then frozen in winter period resulted in interfering with the locomotion and resting behavior of steers. Average daily dry matter intake of steers was not different between tow treatments, however, the average daily gain of steers in NP and SP was 0.64kg and 0.75kg, respectively, meaning that gained 14.3% less for the NP group(p<0.05), accordingly, feed requirement(feed/gain) and TDN/gain increased by 15.9% and 15.5%, respectively. No significant differences were found in slaughter weight, carcass weight, dressing percentage, meat yield index and meat quality traits between two treatments. In conclusion, this study revealed that poor floor condition of feeding pen could decrease weight gain and feed efficiency of cattle by increasing energy consumption for locomotion and conductive energy loss while resting on the floor surface. These results indicates that housing orientation of cattle shed and the selection of roof material are important factors in beef cattle production.

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