• Title/Summary/Keyword: steel wire rope

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Enhancing seismic performance of ductile moment frames with delayed wire-rope bracing using middle steel plate

  • Ghalandari, Akram;Ghasemi, Mohammad Reza;Dizangian, Babak
    • Steel and Composite Structures
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    • v.28 no.2
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    • pp.139-147
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    • 2018
  • Moment frames have considerable ductility against cyclic lateral loads and displacements; however, sometimes this feature causes the relative displacement to exceed the permissible limits. This issue can bring unfavorable hysteretic behavior on the frame due to the reduction in the stiffness and resistance against lateral loads. Most of common bracing systems usually control lateral displacements through increasing stiffness while result in decreasing the capacity for energy absorption. This has direct effect on hysteresis curves of moment frames. Therefore, a system that is capable of both having the capacity of energy absorption as well as controlling the displacements without a considerable increase in the stiffness is quite important. This paper investigates retrofitting of a single-storey steel moment frame using a delayed wire-rope bracing system equipped with the ductile middle steel plate. The steel plate is considered at the middle intersection of wire ropes, where it causes cables to be continuously in tension. This integrated system has the advantage of reducing considerable stiffness of the frame compared to cross bracing systems as a result of which it could also preserve the frame's energy absorption capacity. In this paper, FEM models of a delayed wire-rope bracing system equipped by steel plates with different geometries have been studied, validated, and compared with other researchers' laboratory test results.

Defect Detection of Steel Wire Rope in Coal Mine Based on Improved YOLOv5 Deep Learning

  • Xiaolei Wang;Zhe Kan
    • Journal of Information Processing Systems
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    • v.19 no.6
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    • pp.745-755
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    • 2023
  • The wire rope is an indispensable production machinery in coal mines. It is the main force-bearing equipment of the underground traction system. Accurate detection of wire rope defects and positions exerts an exceedingly crucial role in safe production. The existing defect detection solutions exhibit some deficiencies pertaining to the flexibility, accuracy and real-time performance of wire rope defect detection. To solve the aforementioned problems, this study utilizes the camera to sample the wire rope before the well entry, and proposes an object based on YOLOv5. The surface small-defect detection model realizes the accurate detection of small defects outside the wire rope. The transfer learning method is also introduced to enhance the model accuracy of small sample training. Herein, the enhanced YOLOv5 algorithm effectively enhances the accuracy of target detection and solves the defect detection problem of wire rope utilized in mine, and somewhat avoids accidents occasioned by wire rope damage. After a large number of experiments, it is revealed that in the task of wire rope defect detection, the average correctness rate and the average accuracy rate of the model are significantly enhanced with those before the modification, and that the detection speed can be maintained at a real-time level.

A Fundamental Study for the Sliding Wear Characteristics of the Crane Sheave Against a Rope Wire (크레인시브와 로프소선간의 미끄럼 마멸특성에 관한 기초연구)

  • Ryu, Jung-Buk;Chae, Young-Hun;Kim, Seock-Sam
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.11
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    • pp.1873-1880
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    • 2003
  • The sliding wear characteristics of the crane sheave were investigated using a pin on disk rig tester. The experiment was conducted using a high carbon steel wire that was upper material, also carbon steel castings that was disk material. There are various operating conditions in this work. At the room temperature, we carried out the wear test under a grease lubrication and dry condition. The results of wear test showed that an annealed-casted have lower, also the wear curves are linearly increased with increasing of sliding distance. For the specific wear rate of annealed-casted, the wear resistance was increased with decreasing diameter of wire. The wear of a wire and a disk have a different mechanism, the one is the abrasive wear due to fatigue wear under lubrication, another is the adhesion wear under dry condition.

Axial Behavior of Reinforced Concrete Columns Externally Strengthened with Unbonded Wire Rope and T-Shaped Steel Plate (와이어로프와 T 강판으로 비부착 보강된 철근콘크리트 기둥의 중심 축하중 거동)

  • Yang, Keun-Hyeok;Sim, Jae-Il;Byun, Hang-Yong
    • Journal of the Korea Concrete Institute
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    • v.20 no.2
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    • pp.221-229
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    • 2008
  • An improved unbonded-type column strengthening procedure using wire rope and T-shaped steel plate units was proposed. Eight strengthened columns and an unstrengthened control column were tested under concentric axial load. The main variables considered were the volume ratio of wire rope and the flange width and configuration of T-shaped steel plates. Axial load capacity and ductility ratio of columns tested were compared with predictions obtained from the equation specified in ACI 318-05 and those of conventionally tied columns tested by Chung et al., respectively. In addition, a mathematical model was proposed to evaluate the complete stress-strain relationship of concrete confined by the wire rope and T-plate units. Test results showed that the axial load capacity and ductility of columns increased with the increase of the volume ratio of wire rope and the flange width of T-plates. In particular, at the same lateral reinforcement index, a much higher ductility ratio was observed in the strengthened columns having the volume ratio of wire rope above 0.0039 than in the tied columns. A mathematical model for the stress-strain relationship of confined concrete using the proposed strengthening procedure is developed. The predicted stress-strain curves were in good agreement with test results.

An initial investigation of the inverted trussed beam formed by wooden rectangular cross section enlaced with wire rope

  • Gesualdo, F.A.R.;Lima, M.C.V.
    • Structural Engineering and Mechanics
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    • v.44 no.2
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    • pp.239-255
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    • 2012
  • This work presents a contribution to understand the inverted trussed beams behavior. The system has a main beam and struts with rectangular cross section associated to a wire rope enlaced to the main beam. It is an unpublished system with the advantage of easy positioning of the wire rope, once it is a continuous and connected by turnbuckles. It is a system that can be used as support for concrete formworks or for rehabilitation wooden beams proposal. The enlacement of the cable demands a small notch at the top of the cross section and a cross pin at the bottom. Six inverted trussed beams were tested, with spans of 180 cm with cables diameter of 1/4". Additionally, four simple beams without any external steel cable were also tested with material from the same lot of wood, allowing a comparison in rupture. The results showed capacity gain of around 60% compared to a simple beam. Once the wire rope characteristics and anchoring are very important for structure response, some improvement suggestions for the efficiency of the cables are also presented.

The Sliding Wear Characteristics of Carbon Steel Castings against High Carbon Steel Wire Rods (탄소주강과 경강선재간의 미끄럼 마멸특성)

  • 류중북;채영훈;김석삼
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2001.06a
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    • pp.319-326
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    • 2001
  • The sliding wear characteristics of carbon steel castings were Investigated using a ball on disk type tester. The experiment was conducted using high carbon steel wire rods as ball material and carbon steel castings as disk material and different operating conditions, at room temperature under a lubrication and dry conditions. The results showed that the carbon steel castings appeared average wear volume Is lowed after annealing under a lubrication conditions and wear curve linear Increased. The specific wear rate of carbon steel castings Increased with wire diameter lubrication and dry also Increased 125 times In Ory. The sliding wear mechanism were Investigated due to fatigue wear lubrications and abrasive wear dries also wire Included fatigue and abrasive wear by plastic flow.

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The Sliding Wear Characteristics of the Carbon Steel Castings against High Carbon Steel Wire Rods (탄소주강품과 경강선재간의 미끄럼 마멸특성)

  • 류중북;채영훈;김석삼
    • Tribology and Lubricants
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    • v.19 no.4
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    • pp.223-229
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    • 2003
  • The sliding wear characteristics of the crane sheave were investigated using a pin-on-disk rig tester. The experiment was conducted using a high carbon steel wire that was upper material, also carbon steel castings that was disk material. There are various operating conditions in this work. At the room temperature, we carried out the wear test under a grease lubrication and dry condition. The results of wear test showed that an annealed-casted have lower, also the wear curves are linearly increased with increasing of sliding distance. For the specific wear rate of annealed-casted, the wear resistance was increased with decreasing diameter of wire. The wear of a wire and a disk have a different mechanism, the one is the abrasive wear due to fatigue wear under lubrication, another is the adhesion wear under dry condition.

Assessment of Performance and Cost-Effectiveness for the Rockfall Protection Fence Using a High Carbon Steel Wire Rod (고장력 경강선을 적용한 낙석방지울타리의 성능 및 경제성 평가)

  • Lee, Yong-Joo;Na, Seung-Min;Hwang, Young-Cheol;You, Byung-Ok
    • Proceedings of the Korean Geotechical Society Conference
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    • 2008.10a
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    • pp.910-920
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    • 2008
  • In Korea, more than 70% of the territory consists of mountains. Therefore, the construction of roads and railways has generally involved with a steep rock slope in which the event of rockfalls are often occurred due to the weathered rock conditions and rainfalls etc. This is dangerous when the rock falls into the road and railway on which vehicles and trains are running. In order to prevent such rockfalls, the rockfall protection fence consisting of post, wire rope, and PVC coating steel net has most used at the bottom of rock slopes. In a general practice, an absorbing rockfall energy, 50kJ is specified by the Ministry of Construction and Transportation. However, questions still remain about whether the rockfall protection fence works effectively or not. In this study, a typical wire rope used in the standard rockfall protection fence was replaced by the high carbon steel wire rod and to validate its capacity of rockfall energy absorbing the field rockfall tests were conducted. The testing results show that a new rockfall protection fence using the high carbon steel wire rods can absorb the rockfall energy more than 50kJ and 20% of construction cost was saved in comparison with the previous rockfall protection fence.

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Slope stabilization with high-performance steel wire meshes in combination with nails and anchors

  • Rudolf Ruegger;Daniel Flum
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.11b
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    • pp.3-38
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    • 2000
  • Slope draperies in soil and rock are a well known method to avoid rockfalls into the roads or onto housings. Common wire mesh or a combination of wire mesh and wire rope nets are pinned to the slope by the means of fully grouted nails or anchors. Most of these installations have not been designed to stabilize the slope, but simply avoid the rocks from bouncing. The combination of soil- or rocknailing with a designable flexible facing system offers the advantage of a longterm stabilization of slopes and can replace other standard methods for slope stabilization. The capability to transfer axial and shear loads from the flexible facing system to the anchor points is most decisive for the design of the stabilization system. But the transfer of forces by mesh as pure surface protection devices is limited on account of their tensile strength and above all also by the possible force transmission to the anchoring points. Strong wire rope nets increase the performance for slope stabilizations with greater distances between nails and anchors and are widely used in Europe. However, they are comparatively expensive in relation to the protected surface. Today, special processes enable the production of diagonally structured mesh from high-tensile steel wire. These mesh provide tensile strengths comparable to wire rope nets. The interaction of mesh and fastening to nail / anchor has been investigated in comprehensive laboratory tests. This also in an effort to find a suitable fastening plates which allows an optimal utilization of the strength of the mesh in tangential (slope-parallel) as well as in vertical direction (perpendicular to the slope). The trials also confirmed that these new mesh, in combination with suitable plates, enable substantial pretensioning of the system. Such pretensioning increases the efficiency of the protection system. This restricts deformations in the surface section of critical slopes which might otherwise cause slides and movements as a result of dilatation. Suitable dimensioning models permit to correctly dimension such systems. The new mesh with the adapted fastening elements have already been installed in first pilot projects in Switzerland and Germany and provide useful information on handling and effects.

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