The use of steel deck-plate has continuously increased in slab construction because of efficiency of construction-ability. Slab member is not only resisting the loads but sensitive the deflection. Generally, steel deck-plate slab has higher equivalent moment of inertia than normal RC slab because of its bottom steel plate. In this study, stiffness variation of the various slab was experimentally examined.

본 연구는 경량콘크리트와 GFRP 보강근을 휨보강근으로 사용하여 제작되는 GFRP 보강근 경량콘크리트 슬래브를 교량 슬래브 등에 활용해보기 위한 사전 연구로서, 기존의 철근 콘크리트 슬래브와 GFRP 보강근 경량콘크리트 슬래브의 휨 거동 차이점 분석에 초점을 두었다. 이를 위하여 일련의 슬래브 실험체들을 제작하고 3점 휨 실험 및 수치해석을 행하였다. 실험 결과, GFRP 보강근 경량콘크리트 슬래브 실험체는 GFRP 보강근의 과다보강으로 인하여 실험체 하부에 발생된 초기균열이 하중 재하면의 콘크리트 압축부까지 연결되면서 전단파괴되는 경향을 보였다. 그리고 철근 콘크리트로 제작된 슬래브 실험체에 비하여 무게는 72%이었으며 휨 실험에서의 파괴하중은 58%인 것으로 나타났다. 한편, midas FEA를 이용하여 행한 수치해석 과정은 실험에서 나타난 전단파괴 하중까지 잘 모사하였다. 그러나 GFRP 보강근의 인장강도 대신 탄성계수가 입력값으로 요구됨에 따라 가력되는 하중과 처짐은 실험에서 나타난 전단파괴 이후에도 계속하여 증가하는 경향을 보였다.

Recent developments in technology, the use of complex composite section, such as composite truss girder is increasing. These sections, the tensile stress will be generated internal and external constraints caused by other materials. Thus, the effects of the panel point on the concrete slab was studied through the structural analysis.

Finite element analysis is conducted for investigation of structure behavior of high strength concrete(HSC) column-normal strength concrete(NSC) slab connection according to aspect ratio(h/c). Analysis method is verified through comparison of experiment and analysis. As a result, regarding to the aspect ratio, the ultimate strength of column-slab connection decreased as the column dimension increased while the slab thickness did not influence on the ultimate strength of the connection.

The objective of this study is to evaluate the location of a failure surface generatrix and the punching shear strength of hollow plat slabs. The main test parameters was the location of a starting position of hollow materials that varied between 1d and 3d, where d is effective depth of slab section. Based on test results, the starting position of hollow materials in plat slabs is recommended to be more than 2d to avoid the reduction of concrete punching shear strength.

In this study, A preliminary research has been attempted by design and strength analysis on a series of precast ultra high-strength concrete slab systems in order to evaluate. To compare with conventional reinforced concrete slabs, current slab systems can improve serviceability and ultimate load capacities, crack control, and durability, so as to apply in long span, lightweight, and slender building slab systems.

Precast modular bridge was designed by ultimate strength design method(USD), though it is aimed at development of the world's first permanent bridge applying modular technology. Therefore, it is necessary to review the LSD in order to achieve the goal. In this study, the slab-type precast modular bridge(span 8m) was examined on the stability of bending moment in the longitudinal direction by the LSD.

This study established key factors causing deck slab deterioration based on GPR database of 747 highway bridges, and predicted deck slab damage rates with respect to bridge service life. To minimize the influence of bridge service life on deck slab deterioration, the deck slab damage rate database was corrected based on a linear regression model of bridge service life vs. deck slab damage rate. The corrected deck slab damage rates were analyzed to determine correlation considering the number of snowy days, the amount of snowfalls, the number of freeze-thaw days, average winter temperature, altitude, the amount of deicing chemicals and equivalent traffic volume, and then both the number of freeze-thaw days and the amount of deicing chemicals were determined to be key factors causing deck slab deterioration. The complex deterioration considering both key factors was represented deck slab damage rate charts, and the average deck slab life was derived. The results of this study will be used as a guideline for highway bridge maintenance to identify the progress of deck slab deterioration for a given bridge and predict the time required deck slab rehabilitation.

최근 구조물의 노후화에 따른 급속 교체, 교통 영향 및 환경 영향 최소화의 요구에 따라 프리캐스트 기술을 활용한 모듈러 교량 연구가활발하게 진행중에 있다. 본 연구는 모듈러 교량과 관련된 연구의 일환으로 모듈러 슬래브 교량의 횡방향 연결부를 대상으로 반복하중 재하 실험을 통하여 횡방향 연결부의 반복 하중에 따른 구조적 거동 특성을 파악하고 사용성 평가하였다. 반복하중의 크기를 결정하기 위하여 RC 보를 1개 제작하였으며 반복하중 재하 실험을 위하여 일체형 RC 보 1개와 분절형 실험체 3개를 제작하였다. 실험결과, 분절형 실험체는 하중 반복 횟수가 증가함에 따라 처짐 및 균열폭이 거의 일정하거나 수렴하는 경향을 나타냈으며, 일체형 RC 보와 비교하여 최대처짐, 잔류처짐, 균열폭 모두 작게 나타났다. 또한 사용하중을 반복 재하한 실험체의 경우, 처짐 및 균열에 대한 사용성 기준을 모두 만족하였다.

중공슬래브는 슬래브의 자중을 감소시킴으로써 콘크리트 하중을 제어하여 수직 구조 부재 하중 및 지진 하중의 양을 감소시키는 바닥구조시스템이다. 중공슬래브는 슬래브의 자중을 획기적으로 줄일 수 있지만 슬래브 내부의 중공부로 인하여 휨 및 전단강도가 감소하기 때문에 구조 성능의 예측이 매우 중요하다. 중공슬래브에 관한 국내외의 많은 연구에도 불구하고 일방향 중공슬래브의 전단보강에 따른 전단강도에 관한 연구는 많이 이루어지지 않고 있다. 따라서 본 연구에서는 전단보강 유무에 따른 일방향 중공슬래브의 파괴양상 분석과 산정식의 전단강도와 실험값의 전단강도의 비교를 통하여 일방향 중공슬래브의 전단보강의 필요성에 대해 검증하고자 한다.

The high-strength concrete slab confined by steel members, the possibility of thermal crack due to heat of hydration is high. These thermal cracks, it reduces the serviceability, safety and service life valuation of the structure, it is necessary to review.

An inter-layer noise problem in the apartment has been issued. An fundamental investigation has been carried in this study. An vibration-acoustic interactive analysis, has been selected to see the relationship between concrete slab thickness and its sound level in the apartment. Results showed that the sound pressure level had been decreased when the concrete slab thickness was increased. These results would be helpful to provide an useful information for developing of a high performance floor slab minimizing inter-layer noise.

Depending on the speed up of railway noise problem has become increasingly serious. In general, under the same conditions when the vehicle speed is 300km/h in a 400km/h increases, it is known that an increase in the noise level of 6 to 7dB. Railway Noise can be reduced by improving the vehicle and the track system. Also, the noise barrier and sound absorbing block may be a valid alternative to reduce railway noise. Here we propose a construction method of absorbing blocks are removable to allow maintenance.

합리적인 온도 설계하중을 연구하기 위하여, 실제 크기의 콘크리트 슬래브가 없는 강상형 거더 교량 시험체를 제작하였다. 높이에 따라 부착된 18개의 온도 게이지에서 5개월 동안 온도 데이터를 측정하였다. 강상형 거더 교량 시험체의 상단과 하단 사이의 온도 차가 계산되고, 온도 구배 모형이 확률 방법으로 제안되었다. 본 연구에서 제시된 모형은 유로 코드에 의해 제안 된 모델과 비교했을 때 약 97%의 상관관계를 보인다. 따라서, 본 연구의 결과로 제안 된 온도 구배 모델은 온도 설계 하중 계산시 기초 자료로 활용 될 수 있다.

Recently, modular technologies have been developed in nuclear power plant structures and bridge structures. In addition, they can be utilized in the underground structure of near surface transit system. In this study, the research and development plan of the modular slab structure and construction technology for near surface transit system described.

A composite precast slab will be an economical alternative in case of constructing on a extremely cold region like antarctic. Side ratio optimization of the slab should be performed to solve the difficulties of using construction equipments and moving materials. Optimized side ratios by FEM and orthotropic plate theory are calculated and the results can be used to design the composite precast slabs.

Recently, The aims to rapid construction and easy maintenance of the road system. As a part of the precast road construction system, this study investigated the deformations and stresses at the end of the precast slab and checked horizontal filler and vertical anchor bolt. Analysis cases selected by each boundary condition and choose proper boundary condition. as choose analytical model result, developed precise analytical models and checked performance of end tip connection.

In this study, rational prediction models for the effective compressive strengths of HSC corner and interior columns with intervening NSC slabs are developed. A structural analogy between HSC column-NSC slab joint and brick masonry is used to develop the prediction models. In addition, the aspect ratio of slab thickness to column dimension and the surrounding slab confinement effect are considered in the models. The proposed prediction model is verified by comparison with experimental results and various prediction expressions. As a result, with average test-to-predicted ratios of 1.00 for HSC corner columns and 1.09 for interior columns, the proposed equation provides superior predictions over all of the existing effective strength prediction approaches including KCI structural concrete design code(2012).

철근콘크리트 구조물의 전단거동은 수년간의 많은 연구에도 불구하고, 이론적으로 명확하게 규명하기에 어려운 문제중에 하나이다. 중공슬래브의 휨강도와 전단강도는 중공부로 인하여 감소되기 때문에, 이에 따른 구조물의 성능을 예측하는 것은 중요한 문제라 할 수 있다.현재 각국의 중공슬래브 전단설계기준은 실험에 의한 기준식을 제시하고 있다. 따라서 본 연구에서는 철근비에 따른 일방향 중공슬래브 전단강도 산정방법에 관한 연구를 수행하기 위해 실험결과를 분석하고, 전단강도 산정식들을 비교, 분석하였다.