This research is an application of SHCC (Strain harding Cementitious Composite) in concrete shear wall system in order to improve the structural performance of conventional shear walls. Based on experimental loading results, it was observed that the developed SHCC shear walls showed improved strength as well as enhancements in controlling of bending and shear cracks.

In this study, experiment and analysis of high-strength bolt connection under shear fatigue loading was conducted to evaluate reduction of axial force of bolt. Three type of bolt size and initial axial force were applied to specimens. As a results, it was observed that the reduction ratio of axial force, and that would be used to additional parametric study.

In this study, MR(Magneto-Rheological) Grease fluid was developed for compensating the settling phenomena of MR(Magneto-Rheological) fluid which is widely used in semi-active control system. In order to characterize the settling phenomena of the MRG fluid, the experimental comparison was conducted. The control performance assessment of the MRG fluid was also evaluated. As a result, it was verified that the MRG fluid have the sufficient performances to use as a material for semi-active control device.

In this current study evaluated the horizontal shear strength of reinforced concrete pile between pile body and infilled concrete interface. From the calculated results of horizontal shear strength it was found that the interface between pile body and infilled concrete was evaluated to be able to safely resist factored shear stress.

This research, concrete materials used SHCC(Strain harding Cementitious Composite) in RC(Reinforced Concrete) shear walls. We tried to identify the performance of developed shear wall. Specimens were only considered gravity load and designed and detailed in compliance to KCI-2012. Based on the loading experiment results, this study was found that the developed shear walls showed improved strength than RC shear wall in controlling bending and shear crack. The developed　shear wall with minimum shear reinforcement increased the more strength than RC wall with nominal shear reinforcement

The purpose of this study is to establish a reasonable analytical method for the estimation of overall behavior characteristic from cracking to yielding of rebar and crushing of concrete and seismic performance of reinforced concrete shear wall with high-strength reinforcing bar. A total of 8 specimens of reinforced concrete walls which have constant aspect ratio and a variety of variables such as reinforcement ratio, reinforcement yielding strength, reinforcement details, concrete design strength, section shape and whether lateral restraint hoop were selected and the analysis was performed by using a non-linear finite element analysis program (RCAHEST) applying the proposed constitutive equation by the authors. The mean and coefficient of variation for maximum load from the experiment and analysis results was predicted 1.04 and 8%. The mean and coefficient of variation for displacement corresponding maximum load from the experiment and analysis results was predicted 1.17 and 19% respectively. The analytical results were predicted relatively well the fracture mode and the overall behavior until fracture for all specimens. These results are expected to be used as basic data for application of high-strength reinforcing bar to design codes in the future.

This study was made to examine the motion characteristics according to the reinforcement of the reinforcement length and stiffener reinforcement for shear reinforcement to the foundation structure reinforced with shear reinforcement steel plate. Experimental study was made after specimen was installed on the ground as the same as in the practical site. Reinforcement lengths of the steel for shear reinforcement are divided into 1,000 mm, 1,200 mm and 1,400 mm in the specimen and as for reinforcement method of the stiffener, 4 stiffeners with interval of 100mm reinforced with the same materials as the shear reinforcement were manufactured for the experiment. Considering result of the experiment, it is expressed that no effect of the stiffener reinforcement was found and regarding the reinforcement length of shear reinforcement material the crossed point of the two converted lines of the value that the shear force is expressed in the bearing power in the expanded dangerous section and the value that the shear capacity receivable by the reinforcement materials in the dangerous section is proposed as effective reinforcement length.

In this study, experiment and analysis of high-strength bolt connection under shear fatigue loading was conducted to evaluate reduction of axial force of bolt. Three type of bolt size and initial axial force were applied to specimens. As a results, it was observed that the reduction ratio of axial force, and that would be used to additional parametric study.

In this study, MR(Magneto-Rheological) Grease fluid was developed for compensating the settling phenomena of MR(Magneto-Rheological) fluid which is widely used in semi-active control system. In order to characterize the settling phenomena of the MRG fluid, the experimental comparison was conducted. The control performance assessment of the MRG fluid was also evaluated. As a result, it was verified that the MRG fluid have the sufficient performances to use as a material for semi-active control device.

본 연구는 원형 천공된 플랫 형태와 팔각형 형태의 중공을 가지는 슬래브의 전단강도를 평가하고 있다. 최근 건축구조물에서 슬래 브 두께에 대한 증가와 품질관리에서 요구되는 수준이 상향됨에 따라 프리캐스트 중공 슬래브 시스템에 대한 관심이 증가하고 있다. 중공 슬래 브 시스템은 널리 알려진 바와 같이 슬래브의 자중을 감소시킬 수 있는 효율적인 바닥시스템이다. 하지만 중공슬래브는 전단에 저항하는 슬래 브 웨브의 콘크리트 면적 감소로 전단강도 성능이 저하될 수 있다. 특히, 프리캐스트 중공슬래브는 PC 슬래브 데크의 접합면이 발생하며, 접합 면의 균열로 인한 전단파괴가 일어나지 않도록 방지하여야 한다. 본 연구에서는 I-슬래브 시스템의 전단강도를 평가하기 위하여 3점 가력에 의 한 주축 및 직교축에 대한 전단 실험을 실시하였다. 실험결과 I-슬래브가 PC 접합면이 포함되어짐에도 불구하고 이론강도에 대하여 충분한 전 단강도 성능을 보유하는 것으로 나타났다.

This study has been suggested a model for the in-plane shear behavior of High-Performance Cement-free Fiber Composite Panels under biaxial stress states. The analytical model is verified by comparison of the analytical results with the experimental results for biaxial shaer test of Cement-free Fiber Composite Panels.

Shear capacity of a Textile Reinforced Concrete (TRC) was investigated by an experimental study. Control beam (unstrengthened) and eight beams strengthened with TRC were fabricated to confirm the reinforcing performance in this study. Test variables considered the number, width, spacing of TRC, and reinforcing method accordance with type of attachment. As a results, it was validated that the shear capacity of beams strengthened with TRC in comparison with unstrengthened beam increased from 11.4% to 54.3% according to the amount of TRC. Experimental results indicated an increase in both load carrying and deformation capacities, and also ductility when using multiple layers of textile.

This study investigated the shear behavior of hollowed-head precast reinforced concrete(HPC) pile. In order to evaluate shear strength of the pile, two specimens were manufactured and shear strength test was performed based on KS F 4306 Standard. From the test result it was found that the flexural and inclined cracks were appeared and crack widths were controlled within the shear span up to maximum loads as well as did not appear the abrupt fracture. The average maximum shear load was measured 823.6 kN.

본 연구는 고강도 섬유보강 시멘트 복합체(UHSCC) 접착성능을 평가하는 것이 목적이다. Direct shear test를 통해 압축전단접착강 도를 측정한 결과 NC(보통강도콘크리트)+ NC 실험체(150×150×150)에서는 모든 수준에서 유사한 압축전당접착강도를 나타내었고, 반 면 UHSCC+UHSCC에서는 지연타설 30분 후부터 0분에 비해 압축전단접착강도가 낮아지는 것을 확인할 수 있었다. 이를 통한 접착면의 파괴 모드를 분석한 결과 NC+NC 에서는 모든 수준에서 비계면 파괴를 보였고 UHSCC+UHSCC에서는 30분, 60분, 90분 시험체에서 계면파괴가 일 어났다. NC 및 UHSCC의 타설면을 XRD 시험을 통해 분석한 결과 NC 시험체에 비해 UHSCC의 시험체 에서 많은량의 SiO2의 성분이 검출되 는 것을 알 수 있었고 UHSCC에서 나타난 코팅막의 주성분의 대부분은 SiO2로 사료된다. 따라서 본 연구에서 사용된 UHSCC는 지연타설 30분 후 부터는 접착성능의 저하로 구조체로서의 사용이 어렵다고 판단된다. 금후 연구에서는 콜드조인트 발생 부위의 면처리 방법을 통한 접착성 능 향상이 필요하다고 사료된다.

This study is, when we pour the concrete, doing bonding shear performance evaluation to search the influence about an adhesive interface by a generated cold joint with a retardation time. In conclusion, this experiment shows that the higher a compressive strength of the concrete is, the higher a reduction ratio of the bonding shear strength is, and the instance of a none agitation and a compaction with 15 minutes of a retardation time are the lowest influence in a whole of the results; each of the reduction ratio of the bonding shear strength is approximately 4.5%.

The capacity of post-installed anchor used in joining of new and old concretes structures is dominated by shear force of steels. Thus, too many anchors are required to demonstrate the reinforcement effects. In this study, a new ring anchor with high-shear resistance capacity is presented. This study evaluated that shear capacity by concrete strength and beam width through nonlinear analysis.

The purpose of this study is to apply performance-based seismic design guideline to high-rise shear wall building. According to PEER TBI Guideline, the building is evaluated whether it satisfies the performance objectives which is to be capable of elastic response under Service Level shaking having a return period of 43years and to withstand Maximum Considered Earthquake shaking with prevention collapse.

Recently, studies of eco-friendly construction materials have been increased. For this reason, this paper presents the material properties of steel fiber reinforced slag concrete. Direct shear, flexural, and CMOD tests were conducted to determine the shear and flexural contribution of steel fiber.

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.