• Structural Engineering and Mechanics
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• 제58권1호
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• pp.39-58
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• 2016

Since the publication of ACI 318-02, the concrete capacity design (CCD) method has been used to determine the resistance of unreinforced concrete anchors. The regulation of steel-reinforced anchors was proposed in ACI 318-08. Until ACI 318-08, the shear resistance of concrete breakout for an unreinforced anchor during an earthquake was reduced to 75% of the static shear strength, but this reduction has been eliminated since ACI 318-11. In addition, the resistance of a hairpin-reinforced anchor was calculated using only the strength of the steel, and a regulation on the dynamic strength was not given for reinforced anchors. In this study, shaking table tests were performed to evaluate the dynamic shear strength of unreinforced and hairpin-reinforced cast-in-place (CIP) anchors during earthquakes. The anchors used in this study were 30 mm in diameter, with edge distances of 150 mm and embedment depths of 240 mm. The diameter of the hairpin steel was 10 mm. Shaking table tests were carried out on two specimens using the artificial earthquake, based on the United States Nuclear Regulatory Commission (US NRC)'s Regulatory Guide 1.60, and the Northridge earthquake. The experimental results were compared to the current ACI 318 and ETAG 001 design codes.

• 한국구조물진단유지관리공학회 논문집
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• 제5권3호
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• pp.141-152
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• 2001

This paper presents the evaluation of behavior and the prediction of tensile capacity of anchors that can cause a failure of the concrete on the basis of the design for anchorage. Tests of cast-in-place headed anchors, domestically manufactured and installed in uncracked and unreinforced concrete member are conducted to test the effected of embedment length and edge distance. The failure modes and the load-deformation responses of the anchors are discussed and then the concrete failure data are compared with capacities by the two present methods : the 45 degree cone method of ACI 349, 318 and the concrete capacity design (COD) method. Differences between the results by test and by two prediction methods are analyzed Finite Element Method (FEM).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.491-496
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• 2000

This paper presents the evaluation of behavior and the prediction of tensile capacity of anchors that fail concrete, as the design basis for anchorage. Tests of cast-in-place headed anchors, domestically manufactured and installed in uncracked, unreinforced concrete are performed to investigate the behavior of single anchors and multiple anchors with the consideration of various embedment lengths and edge distances. The failure mode and the load-deformation response of these anchors are discussed and the concrete failure dta are then compared with capacity predictions by the two existing methods : the 45 degree cone method of ACI 349, 318 and the concrete capacity design (CCD) method. Discrepancies between the test results and these two prediction methods, FEM analysis are assessed.

• 한국공간구조학회논문집
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• 제23권2호
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• pp.53-60
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• 2023

Recently, a novel cast-in specialty insert was developed in Korea as an anchor for lightweight pipe supports, including fire-protection pipes. As these pipe supports and anchors play a critical role in transferring loads of fire-protection pipes to structural members, it is crucial to evaluate their seismic performance before applying the newly developed insert. In this study, the seismic shear performance of the insert anchors was evaluated through cyclic loading tests based on the loading protocols of ACI 355.2 and FEMA 461. Initially, five monotonic loading tests were conducted on the insert anchors in cracked concrete, followed by cyclic loading tests based on the monotonic test results. The findings revealed that the insert anchors exhibited negligible decrease in shear strength even after cyclic loading. Furthermore, a comparison of the maximum load and displacement of the insert anchors obtained under the loading protocols of ACI 355.2 and FEMA 461 was performed to investigate the applicability of the FEMA 461 loading protocol for anchor performance evaluation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.151-152
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• 2020

Recently, concrete expansion anchors which are a type of post-installed mechanical anchors are widely used in reinforcement concrete structures. In order to be used in the reinforced concrete structures designed in accordance with ACI 318-19 or ACI 349-13, the structural performance tests of the concrete expansion anchors should be conducted in accordance with ACI 355.2. The effectiveness factor(k) of concrete expansion anchors should be determined through the reference tests and used for the design of anchorage to concrete according to ACI 318-19 or ACI 349-13. In this study, we will look into the method for determining the effectiveness factor(k) of concrete expansion anchors and anchorage design process of concrete expansion anchors by using the effectiveness factor(k) in accordance with ACI 349-19.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.425-428
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• 1999

This paper presents the evaluation of behavior and the prediction of tensile capacity of anchors that fail concrete, as the design basis for anchorage. Tests of cast-in-place headed anchors, domestically manufactured and installed in uncracked, unreinforced concrete are performed to investigate the behavior of single anchors and multiple anchors with the consideration of various embedment lengths and edge distances.

• 한국강구조학회 논문집
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• 제27권1호
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• pp.87-97
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• 2015

본 연구에서는 균열콘크리트에 매입된 선설치앵커의 정적 전단하중에 대한 콘크리트 파열파괴강도 평가 실험을 수행하였다. 이를 위해 앵커 직경 30mm, 연단거리 150mm, 매입깊이 240mm인 비균열 시험체 2개와 전단하중에 수직한 방향과 평행한 방향의 균열을 모사한 시험체 각각 3개씩에 대해 실험을 수행하였다. 실험으로부터 하중 직각방향 균열 시험체는 비균열 시험체에 비해 강도의 저하가 없었으며 하중 평행 방향 균열 시험체는 91%의 강도를 보였는데, 이는 ACI 318-11의 비균열콘크리트의 저항강도의 84%에 해당하였다. 따라서 현재 ACI 318 기준에서 균열콘크리트의 저항강도를 비균열콘크리트 강도의 71%로 고려하는 것에 비해 작은 감소율을 보였다.

• 한국강구조학회 논문집
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• 제27권3호
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• pp.333-345
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• 2015

본 연구에서는 비균열 및 균열콘크리트에 설치된 헤어핀 보강 선설치앵커의 정적 및 동적 저항강도 평가를 위한 연구를 수행하였다. 이를 위해 앵커 직경 30mm, 연단거리 150mm, 매입깊이 240mm에 D10 헤어핀 철근으로 보강한 시험체를 제작하였으며, 균열시험체는 전단하중에 직각방향과 평행방향 균열을 각각 고려하였다. 동적 강도 평가는 지진모의실험에 의하였으며 가력방법은 ACI 355.2의 기준을 적용하였다. 헤어핀 보강 앵커의 저항강도는 콘크리트 균열과는 상관성이 없었으며 동적 강도는 정적 강도와 동등한 수준을 보였다. 마지막으로 헤어핀 보강 앵커의 설계 강도에 대한 고찰을 제시하였다.

• 한국공간구조학회논문집
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• 제21권2호
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• pp.49-56
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• 2021

The damage to non-structural elements in buildings has been increasing due to earthquakes. In Korea, post-installed anchors produced overseas have been mainly used for seismic anchorage of non-structural components to structures. Recently, a new cast-in-place concrete insert anchor installed in concrete without drilling has been developed in Korea. In this paper, an experimental study was conducted to evaluate the tensile and shear strengths of the newly developed anchor under monotonic load. The failure modes of the tension specimens were divided into concrete breakout failure and steel failure, and all shear specimens showed steel failure. In both tension and shear, the maximum loads of specimens were greater than the nominal strengths predicted by the concrete design code (KDS 14 20 54). As a result, it is expected that the current code can also be used to calculate the strength of the developed cast-in anchor.

• 산업기술연구
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• 제33권A호
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• pp.73-80
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• 2013

This paper is results of numerical analysis on the behavior of colluvium slope with combinations of soil nails and earth anchors during excavation. In order to maintain the stability of the colluvium cut, being composed of gravel and boulder and thus local in stability being expected during slope cut, temporary reinforcing method of soil nailing with shotcrete might be used. Subsequent method of cast-in-place facing with earth anchors can be used to maintain cut slope stable permanently. For the cut slope where these methods had been applied, the numerical techniques were applied to their behaviors and investigate the stability of the slope. Limit equilibrium methods were used to confirm to maintain the slope stability during and after excavation and application of those reinforcing methods. Another numerical technique of FEM was also used to find the stress and strain as well as deformation distribution in reinforcing materials and slope ground during excavation.