• Journal of the Korean Society for Advanced Composite Structures
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• v.7 no.1
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• pp.9-18
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• 2016

In this paper, the structural characteristics of a lightweight soundproof tunnel to reduce the dead load imposed on the bridge are investigated. Subsequently, the design procedure of soundproof tunnel structures is reviewed and a design practice for the lightweight soundproof tunnel is carried out according to the reviewed procedure. Next, design compatibility for the lightweight soundproof tunnel is verified through a detailed finite element analysis. The result for evaluation of design compatibility shows that the lightweight soundproof tunnel has structural safety in structural members, welding zones and foundation parts. It is also confirmed that serviceability and buckling safety is excellent.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.25 no.6
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• pp.471-478
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• 2016

This paper describes a method to design a lightweight modular bridge for a railway infrastructure system. A lightweight design was achieved using the material selection method. Aluminum extrusions and honeycomb sandwich composites were selected as the best materials to reduce the weight of the upper structure of a conventional modular bridge made of carbon-steel material. The structural integrity of the lightweight modular bridge was evaluated under vertical and wind loads. The twisting and bending natural frequencies were also evaluated to investigate its dynamic characteristics. The results showed that the structural integrity and natural frequencies of the lightweight modular bridge, made of aluminum extrusion and sandwich composites, satisfied the design requirements. Moreover, it was found that the weight of the conventional modular bridge made of carbon steel could be reduced by a maximum of 47% using lightweight materials.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.5
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• pp.474-479
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• 2013

Mass reduction of the machine tool movable parts is a tool for achieving lower energy demands of the machine tool operation. The realization of lightweight design in machine tool can be achieved by structural lightweight design and material lightweight design. In this study, topology optimization strategy was applied to design optimized structures of movable parts of 5 axis machining center. The weight of ram which has most significant influence on the stiffness of whole machine tool was reduced without stiffness deterioration. The redesigned optimized ram has 24.2% less weight while maintaining the same displacement caused by cutting force.

• 레미콘
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• no.7 s.72
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• pp.29-41
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• 2002

The purpose of this study is to investigarte the mix design method and the mechanical properties of High stength Lightweight Concrete (HSLC). In the experment, concrete mixing was conducted to select the optimum mix design for HSLC in laboratory. Also, concrete mixing in ready mix design. As a result, it is possible to establish the mix design of HSLC according to the using these experimental results ;the estimate equation for unit weight of HSLC. the relationship between W/C and compressive strength of HSLC and the fluidity of HSLC in the view of workability

• Earthquakes and Structures
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• v.6 no.3
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• pp.317-334
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• 2014

The work is concerned with an investigation of the advantages stemming from the use of lightweight aggregate concrete in earthquake-resistant reinforced concrete construction. As the aseismic clauses of current codes make no reference to lightweight aggregate concrete beams made of lightweight aggregate concrete but designed in accordance with the code specifications for normal weight aggregate concrete, together with beams made from the latter material, are tested under load mimicking seismic action. The results obtained show that beam behaviour is essentially independent of the design method adopted, with the use of lightweight aggregate concrete being found to slightly improve the post-peak structural behaviour. When considering the significant reduction in deadweight resulting from the use of lightweight aggregate concrete, the results demonstrate that the use of this material will lead to significant savings without compromising the structural performance requirements of current codes.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.329-330
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• 2010

For the computerization of structural lightweight concrete mix design, mix design theories of ACI211.2-98(Standard Practice for Selecting Proportions for Structural Lightweight Concrete) are investigated and the mix design process is mathematized by Table Curve 2D and 3D software of Jandel company.

• Computers and Concrete
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• v.4 no.6
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• pp.499-510
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• 2007

The densified mixture design algorithm (DMDA) was employed to manufacture high-performance lightweight concrete (LWAC) using silt dredged from reservoirs in southern Taiwan. Dredged silt undergoing hydration and high-temperature sintering was made into a lightweight aggregate for concrete mixing. The workability and durability of the resulting concrete were examined. The LWAC made from dredged silt had high flowability, which implies good workability. Additionally, the LWAC also had good compressive strength and anti-corrosion properties, high surface electrical resistivity and ultrasonic pulse velocity as well as low chloride penetration, all of which are indicators of good durability.

• Korean Journal of Computational Design and Engineering
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• v.18 no.4
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• pp.299-307
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• 2013

Introduction of PLM in domestic shipyards is being retarded as ship PLM has yet to firm up return of investment and process integration. To implement a ship PLM system, it is required to share ship CAD model data in various design and manufacturing environments. Lightweight CAD models provide a promising solution for sharing CAD models in the product life cycle, which can expedite implementation of ship PLM in domestic shipyards in the near future. Compared to proprietary CAD models, it is easy for lightweight CAD models to be interfaced with various application systems and be connected to manufacturing information. In this paper, the reason why lightweight CAD models are necessary to implement a ship PLM system is addressed and current implementation results are introduced.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.488-495
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• 2006

The demand for the use of 3D CAD data over the Internet environment has been increased. However, transmission of 3D CAD data has delayed the communication effectiveness because of the CAD data size. Lightweight CAD file design methodology is required for rapid transmission in the distributed environment. In this paper, to derive lightweight CAD files from commercial CAD systems, a file translation system producing a native file is constructed first by using the InterOp and API of the ACIS kernel. Using the B-rep model and mesh data extracted from the native file, the lightweight CAD file with topological information is constructed as a binary file. Since the lightweight CAD file retains topological information, it is applied to the dimensional verification, digital mock-ups and visualization of CAD files. Effectiveness of the proposed lightweight CAD file is confirmed through various case studies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.49-52
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• 2003

The objective of this study the mechanical characteristics of prefoamed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/㎠ or more compressive strength, when was unit weight 0.8t/㎡. In the case of the same unit weight of concrete, it is influenced by w/c of foam agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufatured with the different factors in mix design and also present optimum mix proportion.