The non-welded building hardware method can reduce accidents caused by welding, and can be constructed by bolt assembly, which can reduce labor costs and shorten the construction period. This study is to compare and verify the performance according to the location where the brackets are joined to the joints using the non-welded building hardware method

In recent years, non-welded building hardware that can be installed by bolt assembly is used, which does not require fire prevention related materials, fire fighting equipment and personnel. However, there is a need for a method to compensate for the occurrence of buckling at the bolted portion at the time of construction.The purpose of this study is to evaluate the behavior of joints that can control the sliding between members by using anti slip brackets.

The purpose of this study is to investigate the bond characteristics of deformed steel bar for concrete with bamboo activated carbon. Pullout test was conducted for specimens with various replacement ratio (0%, 10%, 20%) of bamboo activated carbon. Test results show that it need to use a concrete with a replacement ratio of bamboo activated carbon of 10% or less to retain proper bond strength.

시멘트 생산 과정에서 생성되는 이산화탄소 배출량을 감소시키기 위하여 시멘트를 대체할 수 있는 건축 재료 개발에 많은 연구가 진행되어왔다. 시멘트 대체재로 사용될 수 있는 활성 황토는 850°C에서 소성 과정을 거쳐 제작된다. Poly-Vinyl Alcohol(PVA) 섬유와 GFRP 보강근은 활성 황토 콘크리트의 균열 문제를 해결하기 위하여 사용된다. 본 논문은 PVA 섬유 보강 활성 황토 콘크리트에 대하여 인발 하중에 따른 GFRP 보강근의 부착 성능을 평가하기 위한 실험 연구를 나타내고 있다. 실험 결과, 황토가 치환된 PVA 보강 및 무보강 실험체들의 평균 부착 응력 계수가 2.27~2.48로 나타났으며, 부착 응력 계수가 PVA 섬유 보강 유무 및 황토 치환율에 크게 영향을 받지 않는 것으로 나타났다. 그리고 부착 길이가 길어질수록 부착 강도는 저하되었다.

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.

최근 새집증후군에 대한 문제점으로 인하여 호흡기 및 피부질환 등 여러 문제점들이 발생하고 있음에 따라 친환경 건축재료 또한 함께 대두되고 있다. 그 중 황토콘크리트는 구조재, 바닥재, 마감재 등 여러 부분에 많이 사용되고 있지만, 유지관리 및 안정성의 확보가 중요한 과제로 떠오르고 있음에도 황토콘크리트의 품질관리에 관한 적용성 평가가 미비한 상태이다. 본 연구에서는 응력파기반 비파괴검사법 중 하 나인 충격반향기법과 초음파속도법을 이용하여 황토콘크리트의 압축강도 추정 및 포장두께 추정 검증을 통한 품질관리기술을 제시하고 자바 스크립트를 이용하여 사용자 중심의 품질관리가 가능한 플랫폼을 구현하고자 실험을 실시하였다. 그 결과 황토콘크리트의 압축강도와 초음파 속도의 상관관계를 분석하여 압축강도 추정식을 제안하였으며, 충격반향기법을 이용하여 황토콘크리트 실험체의 실측두께와 추정두께의 오 차율 분석을 통하여 포장두께 추정 적용성을 확인하였다. 또한 취득한 데이터를 바탕으로 자바스크립트와 연계해서 사용자 중심의 황토콘크 리트 품질관리 시스템 플랫폼을 구현하여, 플랫폼으로 사용자중심의 데이터를 취득할 수 있는 가능성을 확인하였다.

The goal of this experimental works is to evaluate the influence of shear strength according to shear span to depth ratio of RC deep beam with high-strength hooked bars. A total of 3 specimens were constructed and tested in three-point bending up to failure. The test variables included the shear span to depth ratio (0.75, 1.0, 1.25). Specimens had a failure mode of shear fracture. For specimen with shorter shear span to depth ratio, it showed that maximum shear strength was higher and that more brittle behavior occurred.

According to social needs, eco-friendly material for concrete structures has been developed in recent years. Hwang-toh is one of the eco-friendly architectural material and hwang-toh has been used by partial or complete replacement of portland cement. Pullout tests on deformed steel reinforcing bars with non-activated hwangtoh concrete are conducted in this paper. Experimental results, average bond strength of non-activated hwangtoh concrete was appeared to 7.3 MPa.

The purpose of this paper is to evaluate the flexural strength and deflections developed of FRC beam with tensile bars composed of two layers combinations of steel bar, GFRP bar, and CFRP bar. As a test result, specimen with CFRP bars had the greatest maximum flexural strength. Specimens with FRP bars had more brittle failure behavior than only steel bars.

This paper presents an experimental study investigating the bond characteristic of steel bars (D13, D16) on fluidity concrete mixed with recycled marble powder under tensile loads. Experimental results showed that average bond strengths of D13 series specimens and D13 series specimens were 18.00MPa and 15.67MPa respectively, and that specimen with the larger diameter of rebar that adhesion strength had the lower bond strength.

This paper is about experimental works to evaluate the effects of fiber reinforcement to shear behavior of RC deep beams with high strength hooked bars. It was planned two specimens with different shear span-to-depth ratio. Specimen had three loading points to induce shear failure. From test results, it showed that maximum shear strength of specimen with shorter shear span to depth ratio was higher.

This paper describes pullout tests on deformed steel reinforcing bars with PVA fiber-reinforced activated hwangtoh concrete (PFRC). Four pullout specimens with the variation of the replacement ratio of PFRC to cement are prepared and test. Experimental results, average bond strength of PFRC was appeared to 19.81. MPa.

The purpose of this study is the implementation platform for quality management of ocher concrete using nondestructive tests. It uses the relationship between the compressive strength and ultrasonic pulse velocity of the ocher concrete to estimate the compressive strength of the ocher concrete. And using the impact echo method to estimate the thickness of the ocher concrete. The platform is based on a Java script, so that the user can obtain the data through the platform.

This paper focuses on the experimental study for investigating the performance for lap splice of hooked or headed reinforcement in beam with different depths. In the experiment, seven specimens, with its variables as the lap length of headed or hooked bar, the existence of stirrups, etc., was manufactured. Bending test was conducted. Lap strengths by test were compared with the theoretical model based on KCI2012. The result showed that the cracks at failure mode occurred along the axial direction to a headed bar. The initial stiffness and the stiffness after initial crack were similar for all specimens. For HS series specimens without stirrups, a 25% increase in lap length was increased 11.8~18.1% maximum strengths. For HH series specimens without stirrups, a increase in lap length did not affect the maximum strengths because of the pryout failure of headed bar. For HS series specimens, the theoretical lap strengths based on KCI2012 considering the B grade lap and the reduction factor for stirrup were evaluated. They are smaller than the test strengths and can ensure the safety in terms of strength capacity. For HH series specimens, the stirrups in the lap zone are needed to prevent the pryout behaviour of headed bar.

The purpose of this paper is to evaluate bond capacity of steel fiber reinforced concrete. Test variables were compressive strength of concrete and steel bar diameter and a total of six specimens in order to examine the discrepancy in bond resistance due to each variable. The specimens were tested by using universal testing machine in displacement control mode. From the test results, it can be seen that the bond strength increased with increasing diameter of steel bar for the same compressive strength of concrete. Also, the higher strength concrete is, the higher bond strength can be found in the test. Significant slip resistance inducing greater bond strength can be observed in the specimens with large diameter steel bar. All the specimens failed in splitting failure after its maximum load and compressive stress of concrete predominated in bond capacity.

Concrete and bar of bond performance used in the most RC structure. So Through recent studies and experiments for the attachment behavior of concrete and steel issues and evaluate their characteristics. Bar are two was used as the D13 and D16. The Bond stress was increased result of experiment by placing a variable length according to the Bond stress formulation according to the diameter and reinforced.

An experimental study was conducted to propose an improved joint in the beam with non-uniform depths of cross-sections. The tested joint detail consisted of headed bars and 180-degree hooked bars. The parameters are the splice length and the confinement effect of strrups in lap zone. The increase of lap length and the confinement detail of strrup reinforcement in the lap zone did not affect the initial stiffness. It can be concluded that the proposed joint detail would be applicable to practical design by using the load transfer mechanism by the effects of confinement details.

In this research, the experimental works were conducted to study the quality control for the compressive strength and pavement thickness of Hwangtoh concrete(21MPa) using the ultrasonic pulse velocity method and the impact echo method of nondestructive test methods based on the stress waves.

최근 연구개발이 활발히 이루어지고 있는 철골 조립식주택은 공장에서 생산되고 현장에서 조립되는 건설방식의 특성으로 인해 일 반 건축물의 철근콘크리트 바닥판과 같이 일체타설 시공되지 못하게 되며 부재 단면크기 감소 및 경량화 등으로 인해 거주자의 활동에 의한 바 닥판의 수직진동 및 처짐이 사용성 평가 측면에서 중요한 문제가 될 수 있다. 따라서 이 연구에서는 대상 조립식주택에서 장변방향 보 중앙에 샛기둥이 설치된 모듈과 설치되지 않은 모듈을 대상으로 실무에서 일반적으 로 사용되고 있는 AISC 설계지침서 11의 계산식(이하 AISC 계산식)을 이용하여 바닥판의 진동성능을 평가하고 범용해석프로그램을 이용한 해석결과와 비교를 통해 AISC 계산식의 적용성을 고찰하였다. 이를 토대로 샛기둥이 설치된 모듈의 바닥판에서 AISC 계산식과 해석결과의 오차가 크게 발생되는 구조적 원인을 분석하고 이를 고려하는 방안을 제시하였다. 또한 대상 조립식주택 바닥판에 대한 진동성능 향상방안을 변수로 해석모델을 수립하고 진동응답해석 및 경제성평가를 통해 진동성능과 경제성이 우수한 방안을 제시하였다.

This survey was conducted to analysis the facilities safety management of presbyterian churches in the central cities and urban areas. As a result, it need to support the knowledge of safety and protestant religious facilities partial help which located in urban areas.