• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.943-953
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• 2006

We investigated experimentally the static behavior of an orthotropic bridge deck which is made from glass fiber reinforced polymer (GFRP) and polyurethane foam. The bridge deck consists of many unit cells with rectangular holes which are filled with the foam to improve its structural behavior in its weak axis. It is found that although the elastic modulus of the foam compared to that of the GFRP is about the order of, the structural behaviors in the weak axis such as nominal strength, stiffness, etc. are greatly improved. Owing to the low mass density of the foam used in this study, the bridge deck is still light enough with the improved structural properties. Webs of the cells filled with the foam did not significantly contribute to the strength development of the deck. However, the propagation of a crack initiated in a cell is caught by the webs and limited to the inside of that cell only, which makes the load-displacement behavior of the foam-filled GFRP deck less brittle.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.171-178
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• 1998

본 연구는 폴리우레탄 콘크리트 패널의 바닥재로서의 이용 가능성을 검토하기 위하여 수행되었다. 따라서 각종 요구되는 성능에 부합되는 배합을 달리한 폴리우레탄 콘크리트를 제작하여 각종 물성 실험을 실시하였다. 또한 폴리우레탄 콘크리트 패널을 제작하여 직접 현장에서의 시공한 수 바닥충격음 실험을 실시, 그 효과를 평가하였다. 실험결과, 폴리우레탄 콘크리트의 성능과 코스트의 밸런스가 적절하게 확보된 최적배합비를 도출할 수 있었으며, 특히 기존 바닥구조에 비해 공동주택의 층간소음을 어느 정도 줄일 수 있고 동시에 시공공정의 단축과 단열효과로 보다 더 우수한 바닥난방구조를 제안할 수 있다.

• Journal of the Korean Wood Science and Technology
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• v.42 no.1
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• pp.20-26
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• 2014

This paper represented the finite element analysis to estimate structural performance of stress-laminated deck, which is determined by deflection, stress, and aging characteristics of tensioning. After loading, the deflected shape showed plate behavior because pre-stressing make frictional force between each member. Compared between initial post-tension and the results, pre-stressing forces were decreased with deck deflection. This is because deflection occurred in the deck so that pre-stressing decreased due to load reduction. However, material plasticity was not considered so that advanced researches should be performed.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.93-102
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• 2007

A large number of FRP decks are already in service worldwide because the lighter FRP-based bridge decks are ideal for rapid construction to reduce the dead load of superstructures. And the proper design process is demanded for the effective FRP deck application. In this paper, to get the basic prototype of FRP bridge decks, the ratio of individual parameters, which compose the specification of FRP bridge decks, are determined by a finite element analysis. In addition, optimum FRP deck shapes are determined considering complex constraints and material properties of bi-directional characteristics. Upon these results, the prototype of FRP bridge decks is validated.

• Journal of Korean Society of Steel Construction
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• v.26 no.4
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• pp.349-359
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• 2014

Until now, wall-slab plate of steel plate concrete has been constructed by joint. But, the shear plate has problems in the workability as well as structural integrity. This study investigates the behavior and strength of rib stiffened SC wall-slab connection. Seven prototype specimens of wall-slab connections were fabricated and tested. the structural safety of the specimens was confirmed through the monotonic loading test. Based on the experimental observations, this study propose the strength formula of the joint was proposed. To enhance the reliability of the proposed strength formula, analytical verification was performed through inelastic finite element analysis. Effect of parameters, such as, load point, friction coefficient, on the joint strength was examined. The proposed formula yields a conservative value for most cases.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.3 s.55
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• pp.145-154
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• 2009

Steel-Concrete Composite Deck with I-beam welded is lighter and easier to construct than conventional in situ reinforced concrete slabs due to the I-beam embedded in the corrugated slab. For the calculation of effective flexural rigidity of conventional reinforced concrete structures, methods suggested in Design Standard for Roads and Bridges and ACI have been used. In this paper, the calculation methods were applied to steel-concrete composite deck with I-beam welded and then results of the steel-concrete composite deck were compared with those of reinforced concrete slabs. In addition, applicability of the methods to steel-concrete composite deck with I-beam welded was estimated. In order to compare the effective flexural rigidity, flexural experiments were conducted. Fifteen slabs were built and the variables considered in the experiments were studs, length of the slab, shape of the section and connecting methods.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.331-340
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• 2008

This study is to suggest the details of new concept of bridge deck. Experimental studies on the behavior of a inverted T-shaped steelconcrete composite deck were carried out. The part of inverted T-shaped steel is embedded in concrete. Reinforced concrete deck specimen and composite deck specimens were fabricated and static bending fracture tests were conducted. The ultimate strength and fracture strength of specimens were evaluated. The effects of shear hole crossing bars of composite deck were also analyzed. From the results of experiments, composite deck with shear hole crossing bar increased shear strength, and showed typical tensile failure. Ultimate strength and fracture strength of composite deck with shear hole crossing bar are higher than those of reinforced concrete deck. The displacement of composite deck is higher than that of reinforced concrete deck.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.184-187
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• 2004

TFT LCD 생산 공정에 사용되는 정밀측정/검사/생산장비가 위치하는 바닥의 진동문제는 크게 장비자체의 가동에 의한 것과 장비외부의 가진원에 의해서 정밀장비의 바닥에 진동이 발생하게 된다. 이러한 진동문제는 건물을 설계 시공하는 건축자의 입장에서는 장비 가동전 건물 인수시 진동문제에 관심이 있으나 장비를 운영하는 사용자의 입장에서는 장비 가동전의 진동문제와 더불어 장비 가동시 장비내부의 진동원에 대해서도 진동대책을 요구하게 된다. 따라서 양자의 진동문제 해결을 위해서는 정밀장비 주변의 진동원에 대한 동하중 설계자료와 함께 장비 가동시 바닥에 진동을 발생시키는 진동원인 장비에 대해서 동하중을 파악하여야 한다. 장비기초의 단위하중에 대한 진동응답을 표현하는 주파수 전달함수는 이러한 동하중과 바닥의 진동허용규제치를 동시에 표현하는 요소로 기존의 정밀장비가 요구하는 장비바닥의 진동허용규제치와 함께 동하중을 유발하는 장비기초에서는 반드시 구조물의 동강성 허용규제치를 이용한 구조물의 동적설계가 요구된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.64-64
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• 2021

댐의 중요 구성요소 중 하나인 여수로 구조물은 관행적으로 단위길이당 100m³/s 정도의 유량이 흐를 수 있도록 설계를 하고, 이를 초과할 때는 여수로 구조물에 피해가 가지 않도록 공기혼입 장치를 설치하거나 콘크리트의 설계강도를 증가시키는 대책을 사용하는 것이 일반적이다(댐설계 기준·해설, 2011) 그러나 건설된 지 오래된 댐의 경우 여수로 콘크리트 구조물의 설계강도가 낮고(최저 16.7MPa) 수문방류 횟수가 많아 최근에 건설된 댐 여수로 보다 상대적으로 많은 손상이 발생되어 있어 잦은 보수보강이 요구되고, 점차 유지관리 비용이 증대되고 있어 노후된 여수로 구조물일수록 기능을 유지하면서도 유지관리 비용을 절감할 수 있는 방안의 수립이 요구되고 있다. 이에 본 연구에서는 𐩒𐩒𐩒댐 여수로를 대상으로 2020년 홍수기 전·후의 여수로 바닥슬래브의 손상상태를 3D드론 매핑, 육안조사 및 내구성 조사결과 등을 이용한 정밀분석을 통해 수문방류시 여수로 바닥슬래브에 가장 큰 손상을 일으키는 손상메커니즘으로 유수에 의한 부상(uplift)에 의한 파손 메커니즘(Flow-driven uplift failure mechanism)을 제시하였으며, 여수로 바닥슬래브의 가장 일반적 손상원인으로 간주되고 있는 공동현상(cavitation)이 공동지수(cavitation index)가 0.3이상인 경우에도 발생할 수 있음을 확인하였다. 이와 같은 관찰 및 분석결과는 보다 많은 사례를 통하여 보완될 경우 향후 여수로 구조물의 설계 뿐만 아니라 보수보강 방법이나 유지관리, 더나아가서는 종합적 댐시설물 자산관리 계획을 수립하는데 매우 유용한 자산이 될 수 있다.

• The Journal of the Acoustical Society of Korea
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• v.42 no.2
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• pp.161-167
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• 2023

Recently, floor impact sound has become a serious social problem in Korea. There is an increasing need to improve floor impact sound performance using floor covering installed on the floor of apartment houses. KS F ISO 717-2 and KS F 2863 require measurement under conditions in which the resilient material is not installed. But most apartment houses in Korea install resilient materials to reduce floor imapct sound. The performance evaluation method of floor covering should provide reduced performance for use by residents of apartment houses with resilient materials. Therefore, this paper proposes a reduction performance evaluation under the conditions in which a resilient material is installed to verify the performance of floor covering.