• Journal of the Korean Society of Mechanical Technology
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• v.13 no.3
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• pp.65-71
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• 2011

The concrete mixer truck which is in charge of raw materials in civil engineering construction of the concrete loading, transport, placement, is used $6m^3$, $7m^3$ class in domestic(Korea). But in the case of the international construction fields are utilized $9m^3$ or above class because of the large-scale engineering and construction circumstances. In this paper, to develop a large $9m^3$ class mixer drum and the mixer drum in order to complement the technical and discharge that is responsible for stirring the blades by applying optimal design through implementation of the optimal shape of the concrete in the drum maintenance and placement of high-quality effects on increasing discharge such as advanced conventional drum mixer is to secure and differentiated technology. Large, heavy weight in development and uphold the drum mixer vehicle sub-frame is required to settle the design of the existing class mixer drum frames per $6m^3$ changed to account for changes in slope and length using CATIA V5 3D modeling work was performed.

• Journal of Drive and Control
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• v.14 no.1
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• pp.1-7
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• 2017

The power train of a concrete truck mixer reducer includes differential planetary gears to get a large reduction ratio for operating the mixer drum in a compact structure. These differential planetary gears are a very important part of the mixer reducer where strength problems are the main concern. Gear bending stress, gear compressive stress and scoring failure are the main concerns. Many failures in differential planetary gears are due to the insufficient gear strength and resonance problems caused by major excitation forces such as gear mating failure in the transmission. In the present study, where the excitation frequencies are the gear tooth passing frequencies of the mating gears, a Campbell diagram is used to calculate differential planetary gear critical speeds. Mode shapes and natural frequencies of the differential planetary gears are calculated by CATIA V5. These are used to predict gear resonance failures by comparing the working speed range with the critical speeds due to the gear transmission errors of the differential planetary gears.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.22 no.2
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• pp.227-235
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• 2024

After the permanent shut down of Kori Unit 1, various decommissioning activities will be implemented, including decontamination, segmentation, waste management, and site restoration. During the decommissioning period, waste management is among the most important activities to ensure that the process proceeds smoothly and within the expected timeframe. Furthermore, the radioactive waste generated during the operation should be sent to a disposal facility to complete the decommissioning project. Square and cylindrical concrete re-package drums were generated during the 1980s and 1990s. The square, containing boron concentrates, and cylindrical, containing spent resin, concrete re-package drums have been stored in a radioactive waste storage building. Homogeneous radioactive waste, including boron concentrates, spent resin, and sludge, should be solidified or packaged in high-integrity containers (HICs). This study investigates the sequential segmentation process for the separation of contaminated and non-contaminated regions, the re-packaging process of segmented or crushed cement-solidified boron concentrate, and re-packaging in HICs. The conceptual design evaluates the re-packaging plan for the segmented and crushed cement-solidified waste using HICs, which is acceptable in a disposal facility, and the quantity of generated HICs from the treatment process.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.11 no.4
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• pp.271-280
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• 2013

Since the decommissioning of nuclear plants and facilities, large quantities of slightly contaminated concrete waste have been generated. In Korea, the decontamination and decommissioning of the KRR-1, 2 at the KAERI have been under way. And concrete waste was generated about 800 drums of 200 L. The conditioning of concrete waste is needed for final disposal. The concrete waste is conditioned as follows: mortar using coarse and fine aggregates is filled void space after concrete rubble pre-placement into 200 L drum. Thus, this research has developed an optimizing mixing ratio of concrete waste, water, and cement and has evaluated characteristics of a cement waste form to meet the requirements specified in disposal site specific waste acceptance criteria. The results obtained from compressive strength test, leaching test, thermal cycling test of cement waste forms conclude that the concrete waste, water, and cement have been suggested to have 75:15:10wt% as the optimized mixing ratio. Also, the compressive strength of cement waste form was satisfied that including fine powder up to maximum 40wt% in concrete debris wastes about 75%. As a result of scale-up test, the mixture of concrete waste, water, and cement is 75:10:15wt% meet the satisfied compressive strength because the free water increased with and increased in particle size.

• Korean Journal of Heritage: History & Science
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• v.37
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• pp.91-120
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• 2004

The Yan mountain area of the northern part of Hebei province and its local neighbor area is categorized main-distribution area of the northern bronze culture of the Eastern Zhou period(770bc~221bc). Recently, it was discovered the concrete character of the culture by a large scale excavation of the Yuhuangmiao cemetery at Jundu mountain. In the chinese scholarship, the cultural character of this area has established the independent cultural type that is distinguished from the Bronze culture of existing. In this paper, I have as a target of analysis remains relate to the Yuhuangmiao culture of the mountain area of northern Hebei in the Eastern Zhou period. And I would like to judge about diverse infuluential relationships of the character of the Yuhuangmiao curture and the Bronze culture, especially burials, burial customs and the characters of the excavated article. In particular, diverse infuluential relationships of the upper Xiajiadian culture Ordos bronze culture and The Central Plains cultural from The Yan state have a important meaning to understand about the character of the Yuhuangmiao culture and the beginning development process. Ultimately, it is peculiar characters of the Yuhuangmiao culture that a shaft gave with stone compartment protecting a coffin as a symbolic form, mask-burial customs such as mainly burials of the living with the dead dogs, a drum shaped jar, a tripod jar with two handles, a short bronze sword with circle hilt, Central Plains cultural bronze containers, bronze halberd and horse-shaped accessories of cartage horse trapping are distinguished from a local neighbor, the bronze culture from northern. The territory of time-space of The Yuhuangmiao culture can be dominately recognized bewteen the upper Xiajiadian culture and Ordos bronze culture. It is the Yan culture after the middle Warring States Period considering with the peculiar chacters which reflected by burials and bural customs and diverse infuluential relationships with peripheral cultures.