• Proceedings of the Korean Society of Disaster Information Conference
• /
• 2016.11a
• /
• pp.198-199
• /
• 2016

기존 콘크리트 구조물의 내력 및 처짐에 저항하기 위하여 섬유시트를 사용한 복합섬유 패널 보강재를 셋 앵커를 이용하여 콘크리트 구조물과 일체화시키는 공법을 개발하였다.. 본 연구에서 적용된 실험 결과에 의하면 엥커+에폭시 보강 I 시험체가 기준시험체에 비하여 최대하중이 3.13배 증가, 동일 앵커갯수인 앵커보강시험체에 비하여 1.14배 증가하여으며, 에폭시보강시험체는 기준시험체에 비하여 최대하중이 3.08배 증가하였으나 계면에서 섬유박리로 인한 취성 파괴가 발생하였다.

• Journal of the Korean Geotechnical Society
• /
• v.16 no.5
• /
• pp.213-226
• /
• 2000

지반 앵커(이하에서는 "앵커"로 칭한다)는 앵커두부, 자유부, 정착부로 나누어져 있다. 현재 주로 사용되고 있는 앵커는 지반과 앵커체 표면의 마찰저항력에 의해 지지하는 마찰방식이며, 앵커체에 발생하는 응력에 따라 크게 인장형과 압축형 앵커로 나누어진다. 그런데, 현재까지 이들 앵커의 설계 및 극한하중의 결정은 대부분이 인장형 앵커에 대한 것으로서, 긴장시 압축형 앵커의 선단정착부의 응력집중으로 이한 그라우트 압축저항에 대해서는 명확히 연구되어져 있지 않다. 본 연구에서는, 현장과 비슷한 조건에서 실내시험을 실시하여 선잔 장착부 그라우트의 보강형식에 따른 압축거동특성과 보강효과, 지반의 구속(정지와 포아송 구속)을 고려한 압축형 앵커의 선단 정착부 그라우트 압축저항력 산정식을 제안하였다.정식을 제안하였다.

• Journal of Korean Society of Steel Construction
• /
• v.26 no.1
• /
• pp.21-30
• /
• 2014

In this study, an experimental study was performed to evaluate the shear resistance of cast-in-place(CIP) anchors reinforced with hairpin and stirrup bars under static and dynamic loads. The reinforcement was developed using D6 bars, and the anchors were installed with 20mm diameter and 120mm edge distance. Three tests were conducted for each type of reinforced anchor under static and dynamic shear load with a pulsating frequency of 1 Hz, respectively. It was found that the strength of hairpin-reinforced anchor was affected by the concrete cover and the dynamic tests showed no capacity reduction of anchors compared with static tests. The stirrup-reinforced anchor showed little increase of resistance compared with unreinforced anchor and the resistance under dynamic loading showed nearly same strength by static loading.

• Tunnel and Underground Space
• /
• v.16 no.2 s.61
• /
• pp.146-155
• /
• 2006

The target slope of this study, formed during the construction of highway, is the very high infinite slope where sliding began along the discontinuity. Although an attempt was made to stabilize the upper part of the slope by installing the rock anchors, large scale failure was occurred at the lower part if the reinforced area. Afterwards, subsequent failures were observed two times. To investigate the cause of the failure, residual shear strength was measured by performing the direct shear test of rock specimen of the site. The anchor design was based on the pull-out test. Considering the slope surface where the undulation was severe and the variation of strength was very large, buttressing was used to obtain the required anchoring capacity.

• Journal of Korean Society of Steel Construction
• /
• v.30 no.2
• /
• pp.67-76
• /
• 2018

An experimental study was conducted to evaluate the breakout strength of stirrup-reinforced cast-in anchors under dynamic shear loadings. The shear loadings were applied in the manner specified in the ACI 355.2 and ETAG 001 for the seismic qualification tests. Test specimens were fabricated with M36 anchor (edge distance, 180mm) reinforced with D10 stirrups (spacing, 100mm). The specimens reached almost the breakout strength and thereafter fracture of anchor occurred. Additional tests with M42 anchor (edge distance, 160mm) reinforced with D6 bars (spacing, 100mm) were also conducted. The experimental results showed that the dynamic shear strength was not less than the static resistance. Based on the test results, it was shown that ACI 318 and ETAG 001 specifications estimate the breakout strength of stirrup-reinforced anchors conservatively as more reinforcement is provided.

• Journal of Korean Society of Steel Construction
• /
• v.27 no.3
• /
• pp.333-345
• /
• 2015

This study evaluated the static and dynamic shear strength of cast-in-place anchors reinforced with hairpin bars in uncracked and cracked concrete. The anchors 30mm in diameter reinforced with D10 hairpin bar were designed with an edge distance of 150mm and an embedment depth of 240mm. The cracked specimens consisted of the orthogonal and parallel cracks to the direction of shear loads, respectively. The dynamic strength was evaluated using seismic qualification tests based on the ACI 355.2 standard. The shear strength of the hairpin reinforced anchor was hardly correlated to the concrete cracks and the dynamic strength was similar to its static shear strength. Finally, a consideration on the design strength of hairpin reinforced anchors was presented.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.453-456
• /
• 2008

Fiber composite is high anticorrosive, high strength and low weight ratio of strength(1/4 of reinforcing bar) so that strengthens concrete structures without increase of additional weight. But fiber composite has a brittle character which increases to the maximum stress point lineally and is suddenly destroyed. Hybrid fiber composite is developed to overcome weakness of fiber composite. The hybrid fiber composite is manufactured by bar type and consists of 9:1 volume ratio(glass : carbon). In this study the result indicates that it is purposed to find out reinforcing characteristics of hybrid fiber composite fixed with impact anchor.

• Journal of Korean Association for Spatial Structures
• /
• v.10 no.4
• /
• pp.103-111
• /
• 2010

Most of apartments, buildings and venues today were built without consideration of earthquake when there was no mandate for an earthquake-resistant design. To reinforce such construction, a compressive method of steel plate is widely used. In spite of continuous researches on the compressive method of steel plate, it has not been systematically evaluated for the effects of various factors affecting the structural behavior of beam and its effect on intensity and failure. Therefore, this study aims to determine the flexural behavior of beam due to Anchor conjugation through the materials obtained by making load test for the Anchor conjugated steel plate while the anchor is set as variable.

• The Journal of Engineering Geology
• /
• v.30 no.4
• /
• pp.515-523
• /
• 2020

If the safety factor does not secure the safety factor suggested in the design standard at the slope design stage, the safety factor is secured by installing an anchor. Stability analysis is used to verify the effect of reinforcing the slope of the anchor, but in this process, most of the anchor construction intervals are assumed to be equal and analyzed. For economical and effective slope reinforcement, stability analysis is required by adjusting the anchor construction interval. In this study, the effect of the anchor construction interval on the change of the safety factor of the slope was identified. Stability analysis was performed by setting a virtual slope with two berms and different anchor construction intervals. As a result of the analysis, the stability of the slope is secured when the anchor spacing of the lower surface is narrowed and the anchor gaps of the upper and middle surfaces are wider than when anchors are installed at the same intervals on the upper, middle, and lower surfaces of the slope. The result was a 15% reduction in the amount of anchors. This means that, rather than reinforcing anchors at the same intervals, it is economical and effective to have an economical and effective reinforcement effect to vary the anchor construction intervals according to the slope characteristics.

• Geotechnical Engineering
• /
• v.10 no.2
• /
• pp.69-84
• /
• 1994

In the present study, the application of a method of anchored or waste tyre wall in reinforcing the unstable slope is investigated. For design purposes a method of external stability analysis of the reinforced slope, together with a method of internal stability analysis of a wall itself, is presented. In order to predict the passive resistance expected in the anchor or waste tyre Meyerhof's bearing capacity theory is moapaed and experimental results of stress distribution of a pile section under lateral loading is used. Hurray's pull-out teat results are compared with the passive resistances of anchors predicted by the proposed method, and alto the advantages in design are compared with a method of reinforced earth wall with steel strips. Finally a design example of reinforced slope using anchored or caste tyre wall is presented and the overall stability is analyzed in detail by the proposed method of analysis. The efficiency of a method of anchored or waste tyre wall is further analyzed, comparing with a method of changing geometry of the origin리 unstable slope.