• Composites Research
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• v.37 no.2
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• pp.86-93
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• 2024

The inner foam structure plays an important role in the performance of the carbon-fiber-reinforced plastic (CFRP) rear spoiler used in automobiles. However, there is still a lack of studies for the CFRP-based rear spoiler according to the type of inner foam, especially under the high-speed driving condition. With this motivation, we numerically analyze the performance of the CFRP rear spoiler using various cases of the inner foam under the highspeed driving condition. Here, polymethacrylimide (PMI), polyvinyl chloride (PVC), and styrene acrylonitrile (SAN) resins are employed as the inner foams in this work. The performances are evaluated using the deformation aspects and vibration characteristics when the driving condition is a high-speed condition (200 km/h). Furthermore, to specifically verify the importance of the inner foam in the high-speed condition, we additionally investigate the performance of the CFRP rear spoiler without the inner foam structure (i.e., hollow type). As a result, it is confirmed that among the types of inner foams utilized in this work, the PMI and PVC inner foams have the best deformation aspect and vibration characteristic, respectively. Note that the hollow-type inner foam has inferior performances compared to other inner foams invoked in this study. Consequently, through this study, it can be confirmed that the inner foam structure can significantly improve the performance of the CFRP spoiler under high-speed driving condition (200 km/h), and also that the strengths of the CFRP spoiler can manifest differently depending on the types of inner foam core.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.123-128
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• 2007

Already, core wall construction method for apartment wall structure and general building special areas applied the engineering method's appropriate examination. Also, trial and error depending on slip-form method is a good examination opportunity to consider. In the present paper's slip-form engineering method l)Casting concrete to slab in sliding 2)RC structure + SRC structure (part of segment) 3)Inside segment variation(straight line-diagonal-circle) are together while determining whether it is possible not to carry out actual construction work on the structure. Finally, small problems continuously appear on actual slip-form method application, design and engineering, starting with planning thoroughly the field examination and diagnosing the atmosphere, minimizing cost, secure work safety facilities characterized by good quality, slip-form research extension, development and decision-making.

• Composites Research
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• v.32 no.5
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• pp.279-283
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• 2019

A flight training simulator of a fully spherical configuration is being developed to precisely and quickly control six degrees of freedom (Dof) motions especially with unlimited rotations. The full-scale simulator should be designed with a lightweight material to reduce inertial effects for fast and stable feedback controls while no structural failure is ensured during operations. In this study, a sandwich composite consisting of glass fiber reinforced plastics and a foam core is used to obtain high specific strengths and specific stiffnesses. T-type stainless steel frames are inserted to minimize the deformation of the sphere curvature. Finite element analysis is carried out to evaluate structural safety of the simulator composed of the sandwich sphere and steel frames. The analysis considers the weights of the equipment and trainee and it is assumed to be 200 kg. Gravity acceleration is also considered. The stresses and displacement acting on the simulator are calculated and the safety is assessed under two different situations.