• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.582-585
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• 2006

Attempts have been applied to reduce the vibration of slab. There are several method in the vibration control of slab from a traditional method such as increment of mass or stiffness of slab to a innovative method augmenting damping of slab. In this study, a attempt has been made to increase the effective damping in slab using the Multi Tuned Mass Damper. we evaluate the reduction effect of the slab selected through numerical simulation and optimization process by applying it to a FEM model. The numerical simulation shows that the effective damping is increased as the number of bean is increased and the vibration control effect is very high.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.498-501
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• 2004

A new slab design using secant stiffness, Direct Inelastic Slab Design, was developed. Since basically the proposed design method uses linear analysis, it is convenient and stable in numerical analysis. At the same time, the proposed design method can accurately estimate the inelastic strength and ductility demands of slab because it can analyzes the inelastic behavior of structure using iterative calculations for secant stiffness. In the present study, the procedure of the proposed design method was established, and a computer program incorporating the proposed method was developed. Design examples using the proposed method were presented, and compared with traditional nonlinear analysis, and experiments. The Direct Inelastic Slab Design, as an integrated analysis/design method, can directly address the design strategy intended by the engineer, such as moment strength and ductility limit. As a result, economical and safe design can be achieved.

• 소음진동
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• 제11권2호
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• pp.276-284
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• 2001

In apartment buildings, floor-impact sound has been regarded as the major source that causes complaints from residents. It is mainly due to the use of light-weight structures and the lack of researches in terms of floor-impact sound. The purposes of this study are analyzing the characteristics of vibration response and sound radiation of 12type void slabs in the improvements void slab by impedance method and finding the fittest improvements void slab on the 12type void slab. The main results of this study are summarized as below: (1) In the $\frac{1}{3}$ octave band level of sound radiation, $\frac{1}{3}$ octave band levels, measured from four-divided improvement void slab(No.8) and eight-divided improvement void slab(No.12), are 10~25 dB lower than that of standard void slab(No.1) in the 1250 Hz. Especially, eight-divided improvement void slab(No.12) is the best void slab in terms of radiation efficiency of sound level. (2) In the correlation relation of acceleration and sound radiation, standard void slab(No.1), four-divided improvement void slab(No.8), SK standard four-hole void slab(No.10), and eight-divided improvement void slab(No.12) are positive correlation relation.

• 소성∙가공
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• 제21권1호
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• pp.58-66
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• 2012

The work roll surface temperature rises and falls repetitively during hot slab rolling because the work roll surface is cooled continuously by water. This study focused on Std. No. 7 to determine a cooling method which significantly reduces the tangential tensile stresses on the work roll surface of the hot slab mill at Hyundai Steel Co. in Korea. A series of finite element analyses were performed to compute the temperature distribution and the tensile stresses in the circumferential direction of the work roll. The virtual slab model was used to reduce the run time considerably by assigning a high temperature to the virtual slab. Except for the heat generated by plastic deformation, this is equivalent to the hot rolling condition that a high temperature slab (material) would experience when in contact with the work rolls. Results showed that when the virtual slab model was coupled with FE analysis, the run time was found to be reduced from 2000 hours to 70 hours. When the work roll surface cooled with a certain on-off patter of water spray, the magnitude of the tangential stresses on the work rolls were decreased by 54.1%, in comparison with those cooled by continuous water spraying. Savings of up to 83.3% in water usage are possible if the proposed water cooling method is adopted.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.487-492
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• 1997

Two-way concrete slab is often modeled as an orthotropic plate. In the modeling, flexural rigidities of the slab which depend upon the re-bar quantity have to be taken into account. Elastic equivalence technique in which the equilibrium and compatibility of the cross-section of slab satisfied is utilized to determine th flexural rigidities. In the analysis Navier's method is applied on the concrete slab with all edges simply supported under inform lateral load. In addition to the analysis using orthotropic plate theory, finite element method is also adopted to suggest the finite element modeling and to investigate the applicability of the method. Results obtained by both methods were compared and it is observed that the difference of the results was increased as the ratio of re-bar quantity increased.

• Steel and Composite Structures
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• 제8권3호
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• pp.217-230
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• 2008

The increasing use of performance-based approaches in structural fire engineering design of multi-storey composite buildings has prompted the development of various tools to help quantify the influence of tensile membrane action in composite slabs at elevated temperatures. One simplified method which has emerged is the Bailey-BRE membrane action method. This method predicts slab capacities in fire by analysing rectangular slab panels supported on edges which resist vertical deflection. The task of providing the necessary vertical support, in practice, requires protecting a panel's perimeter beams to achieve temperatures of no more than $620^{\circ}C$ at the required fire resistance time. Hence, the integrity of this support becomes critical as the slab and the attached beams deflect, and large deflections of the perimeter beams may lead to a catastrophic failure of the structure. This paper presents a finite element investigation into the effects of vertical support along slab panel boundaries on the slab behaviour in fire. It examines the development of the membrane mechanism for various degrees of edge-beam protection, and makes comparisons with predictions of the membrane action design method and various acceptance criteria.

• 한국철도학회논문집
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• 제10권3호
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• pp.296-305
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• 2007

A numerical method for the analysis of train/slab-track interaction on the settled roadbed is developed based on the already developed analysis method of train/ballast-track interaction. The concrete slabs composed of the upper track concrete layer and the lower hydraulic bonded layer are modelled by a equivalent beam. The supporting stiffness of roadbed is evaluated with the modified boussinesq method suggested by Eisenmann. The track irregularity and the gap between slab and roadbed induced by settlement of roadbed are calculated by the effective method newly presented in this study. The validation of the developed method is investigated by a numerical example. The effects of train speed on train and slab track on the settled roadbed with sinusoidal shape of wave length 20m and amplitude 20mm are reviewed.

• 콘크리트학회논문집
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• 제26권5호
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• pp.643-650
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• 2014

일반적으로, 철근콘크리트 슬래브는 재료의 열적특성에 의해 높은 수준의 화재 저항 성능을 보유하고 있다. 그러나, 중공슬래브의 경우 일반 철근콘크리트 슬래브와는 다른 온도분포 및 화재 저항 성능을 보유하고 있을 것으로 예상된다. 중공슬래브는 콘크리트의 축열 효과를 발생시키는 공기층을 만들어내는 중공을 보유하고 있기 때문이다. 이에 연구에서는 중공슬래브의 화재 저항 성능을 평가하는 방법을 Wickstorm이 제안한 방법을 사용하여 제안하였다. 이 연구에서는 본 연구의 연구자가 제안한 도넛형 중공을 보유한 중공슬래브의 화재저항성능에 대한 단순화된 평가 방안을 제시하였다. 또한, 제안된 방법은 중공슬래브에 대한 화재실험을 통해 검증하였다. 이 연구의 결과를 통해 제안된 방법은 화재 발생 이후 중공슬래브의 잔존강도 추정이 가능함을 확인하였으며, 슬래브에 분포되는 온도의 특성을 정확하게 파악할 수 있는 것을 확인할 수 있었다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.401-405
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• 2001

본 연구는 기존의 재래식 슬래브 공법과 새로운 슬래브 공법으로서 적용되고 있는 골형 데크플레이트, 철근트러스 데크플레이트 그리고 내화구조용 데크플레이트 공법의 생산성을 각각 분석 · 비교하였다. 연구의 방법은 재래식 슬래브 공법 및 데크플레이트 공법이 적용되고 있는 건설 현장을 선정하여 비용, 작업 효율성, 품질과 안전성 측면에서 분석을 실시하였다. 본 사례 현장의 경우, 생산성 분석 결과는 다음과 같다. 1. 비용의 측면에서는 내화구조용 데크플레이크 공법이 가장 경제적인 것으로 분석되었다. 2. 작업 효율성 측면에서는 내화구조용 데크플레이트 공법이 가장 우수하였으며, 철근트러스 데크플레이트 공법, 골형 데크플레이트 공법, 재래식 슬래브 공법 순으로 분석되었다. 3. 품질성 측면에서는 내화구조용 데크플레이트 공법이 가장 우수한 것으로 분석되었다. 4. 안전성 측면에서는 재래식 슬래브 공법과 데크플레이트 공법의 경우 추락과 용접에 따른 감전의 위험이 존재하는 것으로 조사되었다. 이상의 자료를 분석 · 비교한 결과, 내화구조용 데크플레이트 공법이 가장 생산성이 우수한 것으로 분석되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 춘계학술논문 발표대회
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• pp.29-31
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• 2007

Building construction in downtown is ever increasing with a strong demand. Top-Down Method is one of suitable construction method for its advantage in minimizing disturbance to neighborhood. Along with these reasons construction site has developed lots of new methods and materials for Time-Cost Trade-off and improving constructability. Opened Slab is one of these method which resist the horizontal force by slab and it has many merit about construction time and unity. We analyze the compression tests on opened slab for the application.