• Proceedings of the Computational Structural Engineering Institute Conference
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• 2005.04a
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• pp.464-470
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• 2005

The numerical analysis is carried out to identify the influence of design factors to shear capacity of cast-in-place (CIP) anchor in ACI 349 Code that is available for the design of fastening system at Nuclear Power Plant (NPP) in this study. The MASA program is used to develop the numerical analysis model and the developed numerical analysis model is verified on a basis of the various test data of CIP anchor. Both $l/d_o$ and $c_1/l$ we considered as design factors. As a result, the variation of $l/d_o$ has no influence on the shear capacity of CIP anchor but $c_1/l$ has a large influence on the shear capacity of CIP anchor, Therefore, it is proved that ACI 349 Code may give a non-conservative results compared with real shear capacity of CIP anchor according to $c_1/l$.

• Structural Engineering and Mechanics
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• v.58 no.1
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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.

• Journal of the Earthquake Engineering Society of Korea
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• v.28 no.6
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• pp.315-323
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• 2024

In this research, the concrete breakout strength in tension of cast-in-place anchors (CIP) is experimentally investigated to be used as fundamental data for the seismic fragility analysis of equipment in nuclear power plants. Experimental variables are chosen, such as the embedment depth of the anchor, single/group anchor configurations, diameter of the head plate, and crack width. Monotonic and cyclic loading are applied to all types of specimens. As measured from the experiments, concrete breakout strength in tension is 1.5 to 2 times higher than the expected strengths from concrete capacity design (CCD) method-based model equations. In alignment with the model's predictions, concrete breakout strength increases with deeper embedment depth, and the strength of group anchors also increases based on the expansion of the projected concrete failure area. This study also explores the effects of head plate diameter and crack width, which are not considered in the model equation. Experimental results show that the diameter of the head plate is not directly correlated to the concrete breakout strength, whereas the crack width is. The presence of cracks, with widths of 0.3 mm and 0.5 mm, leads to reductions of approximately 7% and 17%, respectively, compared to single anchors in non-cracked concrete.

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

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.3
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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).

• Journal of Korean Society of Steel Construction
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• v.27 no.1
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• pp.87-97
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• 2015

In this study, an experimental study was performed to evaluate the concrete breakout strength of cast-in-place(CIP) anchors in cracked concrete under static shear loading. The CIP anchors involved in this study were 30mm in diameter with an edge distance of 150mm and an embedment length of 240mm. The experiment was carried out for two specimens in uncracked concrete and three specimens in cracked concrete orthogonal and parallel to the direction of shear loading, respectively. Compared to the uncracked concrete specimen, cracked specimen orthogonal to the direction of shear loading showed no reduction in the concrete breakout strength and that parallel to the load direction about 91% strength which corresponds to 84% of uncracked concrete strength defined in ACI 318-11. Therefore, the experimental results showed smaller decrease in the shear resistance of CIP anchors in cracked concrete than that specified in ACI code which account for 71% strength of uncracked concrete in cracked concrete.

• Journal of Korean Society of Steel Construction
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• v.24 no.2
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• pp.207-215
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• 2012

The 45-degree cone failure theory has been used in concrete anchor bolts design under shear loading, but the CCD (Concrete Capacity Design) method was adopted as a new design method since 2000. However, the method was allowed only for anchor diameters of less than 50mm because it is based on the experimental results of small size anchor bolts. Therefore, it is necessary to develop a rational concrete breakout capacity equation for medium-to-large size anchor bolts with large edge distance. In this study, shear tests on M56 cast-in-place single anchor bolt with edge distance of 350mm were performed using four test specimens. Based on the test results and findings of existing studies, a new equation for the breakout capacity of anchor bolts under shear loading with edge distance of up to 750mm was proposed.

• Journal of Korean Society of Steel Construction
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• v.23 no.4
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• pp.493-501
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• 2011

The $45^{\circ}$cone failure theory has been used for concrete anchor bolt design, but the CCD (concrete capacity design) method was adopted as a new design method in 2000. The method was allowed to be used, however, only for anchors with a diameter of less than 50 mm and an embedment depth of less than 635 mm because it is based on the experiment results from medium-sized to small anchor bolts. Therefore, it is necessary to develop a rational concrete breakout capacity equation for medium-sized to large anchor bolts. In this study, tension tests on an M56 cast-in-place single anchor bolt with an effective embedment depth of 400-450 mm were carried out for the five test specimens. Based on the test results together with the other recent test results, the applicability of the concrete breakout capacity equation in the current design code to the large to medium-sized anchor bolts with an embedment depth of 280-1,200 mm was estimated.

• Journal of Korean Society of Steel Construction
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• v.26 no.1
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• pp.11-20
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• 2014

The Concrete Capacity Design(CCD) method has been used in the design of anchor since 2001 and Korean design code specify that concrete breakout capacity of CIP anchor under seismic load shall be taken as 75% of static capacity. In this study, an experimental study was performed to evaluate the concrete breakout capacity of unreinforced CIP anchors under dynamic shear force. For the purpose, three static and dynamic shear-loading tests were conducted using 20mm diameter anchors, respectively. The edge distance of 120mm was considered in the tests. In the dynamic tests, 15 cycles pulsating load with 1Hz speed was applied and the magnitude of loading step was increased until concrete breakout failure occurs. From the tests, the concrete breakout capacity under dynamic shear loading showed nearly same capacity by static loading.

• Journal of Korean Society of Steel Construction
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• v.27 no.3
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• pp.347-357
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• 2015

In this study, an experimental study was performed to evaluate the concrete breakout strength of unreinforced cast-in-place anchors by seismic qualification test under shear loading. The CIP anchors tested herein were 30mm in diameter with an edge distance of 150mm and an embedment depth of 240mm in uncracked and cracked concrete. The cracked specimen consisted of orthogonal and parallel crack to the loading direction, respectively. The dynamic loading sequence during the seismic qualification test was determined based on CSA N287.2, ACI 355.2 and ETAG 001 codes. After the dynamic loading, the static loading was applied until failure occurs. The shear resistance by seismic qualification tests showed almost the same strength as that obtained from the static tests in uncrcaked and cracked concrete, respectively. Meanwhile, the breakout depth did not reach $8d_0$, therefore the modified strength equation of ACI 318-11 could estimate properly the concrete breakout strength, which does not consider effective bearing length.