• 한국지진공학회논문집
• /
• 제19권4호
• /
• pp.195-205
• /
• 2015

Various non-seismic tie details are frequently used for one- and two-story small buildings because the seismic demand on their deformation capacities is not relatively significant. To evaluate the effects of the non-seismic tie details on the seismic performance of reinforced concrete columns, six square columns with a cross section of $400{\times}400mm$ and six rectangular columns with a cross section of $250{\times}640mm$ were tested. The anchorage details at both ends and spacing of tie hoops, along with the cross-sectional shape and the magnitude of axial load, were considered as the primary test parameters. Test results showed that square columns had higher stiffness and lower lateral deformation rather than rectangular columns. Both lap spliced tie and U-shaped tie provided comparable or improved seismic performance to $90^{\circ}$ hook tie in terms of maximum strength, ductility, and energy dissipation. The predicted curves with modeling parameters in ASCE41-13 were conservative for test results of lap spliced tie and U-shaped tie specimens since plastic behavior after flexural yielding could not be considered. For economical design, ASCE41-13 should be revised with various test results of tie details.

• Structural Engineering and Mechanics
• /
• 제48권2호
• /
• pp.221-239
• /
• 2013

This paper focuses on a development of strut-and-tie model (STM) to predict the capacity of an improved longitudinal joint for decked bulb-tee bridge systems. Nine reinforced concrete beam/slab specimens anchored by spliced headed bars with different details were tested. Test results were evaluated and compared with an anticipation of the validated STM. The proposed STM provides a lower bound of the ultimate capacity of the joint zone. It shows that the lap length of headed bars has a significant effect on structural behaviors of the improved joint. To develop a full strength joint, the range of the lap length can be determined by the strength and compatibility requirement. Design recommendations to spliced headed bars, concrete strength, as well as lacer bars in the joint zone are proposed for developing a full strength joint.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
• /
• pp.737-742
• /
• 1997

In this paper the effect of tie wire in lap spliced bars is investigated by experiment. The variables considered in the beam behaviors are beam dimension, lapped splice length and numbers of tie wire. 3 test pieces having the same variables consist one series and a total of 6 series ar tested. The test results show the beam behavior is not affected by numbers of tie wire but by the manner of tie. It was revealed hat the load bearing capacity of the beam is increased when the tie wire is extended to top bar.

• 콘크리트학회논문집
• /
• 제16권5호
• /
• pp.687-696
• /
• 2004

철근콘크리트 교각의 시공시 소성힌지구간에서 주철근 겹침이음은 내진성능면에서 바람직하지 않으나 불가피하게 시공되는 경우가 있었다. 특히, 1992년 도로교표준시방서의 내진설계 기준이 마련되기 이전에 설계 시공된 대부분의 철근콘크리트 교각은 소성힌지구간에 주철근을 겹침이음 하였으며, 이들은 휨에 대한 소성영역에서의 거동에 직접적인 영향을 미친다. 본 연구에서는 직경 1.2m, 형상비 4.0의 휨파괴가 예상되는 비내진 및 한정연성시험체를 8기 제작하여 준정적(Quasi-Static)실험을 통한 철근콘크리트(RC) 교각의 소성힌지구간내의 주철근 겹침이음과 횡방향구속력이 내진성능에 미치는 영향을 평가하였다. 실험체의 변수로서는 $0\%,\;50\%,\;100\%$의 주철근 겹침이음, 2종류의 횡구속철근비 및 띠철근 형상을 선택하였다. 연구결과 주철근 겹침이음 정도에 따라 철근콘크리트 교각의 내진성능은 급격히 저하되었으며, 겹침이음이 없는 한정연성설계된 시험체의 경우 높은 내진성능을 발휘하였다. 연구결과에 따라 중저진지역에서 겹침이음된 주철근 교각의 내진성능을 위한 적절한 횡방향철근량을 제안하였다.