• International Journal of Highway Engineering
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• v.19 no.1
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• pp.21-28
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• 2017

PURPOSES : This paper presents a finite element model to accurately represent the soil-post interaction of single guardrail posts in sloping ground. In this study, the maximum lateral resistance of a guardrail post has been investigated under static and dynamic loadings, with respect given to several parameters including post shape, embedment depth, ground inclination, and embedment location of the steel post. METHODS : Because current analytical methods applied to horizontal ground, including Winkler's elastic spring model and the p-y curve method, cannot be directly applied to sloping ground, it is necessary to seek an alternative 3-D finite element model. For this purpose, a 3D FHWA soil model for road-base soils, as constructed using LS-DYNA, has been adopted to estimate the dynamic behavior of single guardrail posts using the pendulum drop test. RESULTS : For a laterally loaded guardrail post near slopes under static and dynamic loadings, the maximum lateral resistance of a guardrail post has been found to be reduced by approximately 12% and 13% relative to the static analysis and pendulum testing, respectively, due to the effects of ground inclination. CONCLUSIONS : It is expected that the proposed soil material model can be applied to guardrail systems installed near slopes.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.2
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• pp.183-187
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• 2011

As larger the commercial vessel is, and rougher the marine environment becomes nowadays, drag embedment type anchor (DEA) of more stable performance and higher holding power is requested to be applied on the vessel. But, the performance of DEA has not become well known to academy and industries so far, that the basic study of DEA performance and holding force for the development of new DEA of higher performance is insufficient that required. In this paper, three types of same holding category DEA model (HALL, AC-14, POOL-N, scale 1/10), which are generally applied on the commercial vessel nowadays, were tested by being horizontally dragged on the test tank, on which sand was being floored with sufficient depth, and measured the holding force of each anchor simultaneously using load cell and D/A converter. With the test results, the embedding motion was analyzed to have three different stages and the holding force of each anchor was analyzed with respect to the anchor geometry, such as shape and weight of each type of anchors, and final embedding depth.

• Journal of the Korean Institute of Educational Facilities
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• v.26 no.4
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• pp.19-25
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• 2019

Concrete wedge anchor is one of structural components to transfer load of an object attached to a primary structure. Recently, as retrofitting concrete structure is becoming a main issue, mechanical capacity of the anchor should be secured enough. In spite of the structural safety of Cast-in-place anchor, Post-installed anchor is more widely used with ease of placement or change of construction method. However, the post-installed anchors domestically produced have excessive coefficient of variation over 15% of ultimate tensile strength, which yields deteriorated quality in tensile strength. In this research, tensile strength test of anchors, which have improved sleeve and header and produced by a domestic company, was conducted for two variables, concrete strength and effective embedment depth. As a result, enough coefficients of variations were secured in all specimens. Also, in comparison to foreign products, the domestic ones have equal or higher performance.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.3
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• pp.55-63
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• 2015

Post-installed concrete set anchors are installed after the concrete hardened. These anchors increasing usage in development of construction equipment and flexible construction. The anchor loaded in shearing exhibits various failure modes such as steel failure, concrete failure, concrete pryout, depending on the shear strength of steel, the strength of concrete, edge distance and anchor interval, etc,. In this study, the objective is to investigate the effects of the variations like anchor embedment depth, edge distance and concrete strength on experimental and finite element analysis of shear failure behavior of post-installed concrete set anchor for light load embedded in concrete. The results of embedment depth experiments show that concrete strength has much affection on the shallow embedment depth. Concrete strength has no much affection with anchor interval and edge distance parameter and both experimental results occurred same failure mode. By comparing the experimental results that occurred steel failure mode show that as strong as concrete strength are the displacement results are small.

• Geomechanics and Engineering
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• v.8 no.4
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• pp.595-613
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• 2015

An experimental investigation into the uplift capacity of horizontal square plate anchors in sand with and without geogrid reinforcement is reported. The parameters investigated are the effect of the depth of the single layer of geogrid, vertical spacing of geogrid layers, number of geogrid layers, length of geogrid layers, the effects of embedment depth, and relative density of sand. A series of three dimensional finite element analyses model was established and confirmed to be effective in capturing the behaviour of plate anchor-reinforced sand by comparing its predictions with experimental results. The results showed that the geogrid reinforcement had a considerable effect on the uplift capacity of horizontal square plate anchors in sand. The improvement in uplift capacity was found to be strongly dependent on the embedment depth and relative density of sand. A satisfactory agreement between the experimental and numerical results on general trend of behaviour and optimum geometry of reinforcement placement is observed. Based on the model test results and the finite element analyses, optimum values of the geogrid parameters for maximum reinforcing effect are discussed and suggested.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.7 no.3
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• pp.175-181
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• 1987

Plugging effect of open-ended pipe piles is known to have a close relationship with the ratio of an embedment depth to a pile diameter, i.e., the relative embedment ratio. To evaluate this relationship in the concrete, load tests are performed on the open and the close ended model piles varying the relative embedment ratio as well as the relative density of the model test ground. Cross-shaped hollow plates are attached at the open pile ends to reduce the effective pile diameters, on which load tests are also performed. As a result, it is confirmed that higher plugging effect may be obtained in the denser ground at lower relative embedment. However, 100% plugging effect can be obtained at the relative embedment ratio of 25 or bigger regardless of the density of the ground. Increment of the plugging effect by introducing the cross-shaped attachment can hardly be achieved.

• Geomechanics and Engineering
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• v.30 no.2
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• pp.123-138
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• 2022

Present study computes the ultimate bearing capacity of an embedded strip footing situated on the rock slope subjected to seismic loading. Influences of embedment depth of strip footing, horizontal seismic acceleration coefficient, rock slope angle, Geological Strength Index, normalized uniaxial compressive strength of rock mass, disturbance factor, and Hoek-Brown material constant are studied in detail. To perform the analysis, the lower bound finite element limit analysis method in combination with the semidefinite programming is utilized. From the results of the present study, it can be found that the magnitude of the bearing capacity factor reduces quite substantially with an increment in the seismic loading. In addition, with the increment in slope angle, further reduction in the value of the bearing capacity factor is observed. On the other hand, with an increment in the embedment depth, an increment in the value of the bearing capacity factor is found. Stress contours are presented to describe the combined failure mechanism of the footing-rock slope system in the presence of static as well as seismic loadings for the different embedment depths.

• Journal of the Korean Geotechnical Society
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• v.21 no.1
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• pp.115-121
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• 2005

At present, continual road constructions to connect from city to city are needed due to the geographical feature of Korea that about $70\%$ of the territory is mountainous area. Thus, the generation of large cut-slope has been inevitably formed. As a means of reinforcement on the cut-slope, in case of destructive disasters such as a snowstorm, pile embedment method is widely adopted. The pile embedment method is to resist possible move of soil by embedding piles from the surface to the immovable ground and then delivering the load from the piles to the immovable ground. In this study this writer analyzes the limitation of empirically used pile construction depth and its spacing through the numerical analysis. As a result, he suggests the most effective pile construction depth and space.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.580-586
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• 2010

The purpose of this study is to analyze the behavior of the concrete pile under the horizontal loads by the model tests in laboratory. The rock ground was modeled by the concrete of about 30MPa, and a model pile was made of some mortar with the capacity of 24MPa. The diameter(D) and length(L) of a model pile was each 1200mm and 1800mm. The embedment depth into the concrete block was varied with 1.0D, 1.5D, and 2.0D in the model tests. The results of model tests showed that the lateral resistance of a pile with the embedment depth of 2.0D was more large than other cases, and the lateral displacement of yielding was similar.

• Journal of the Korean Society of Safety
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• v.17 no.2
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• pp.85-91
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• 2002

A research on the performance of retrofit anchors was conducted using adhesives for rehabilitation. From the pull-out tests of the chemical anchors, the effect of the hole diameter, spacer, temperature, moisture, embedment depth, and aging time were investigated. The spacer did not directly increased the pull-out load hilt increased post-yielding resistance therefore the ductility of the retrofit anchors. When the hole was cleaned and dried after the immersion, the pull-out load was greatly increased compared to the wet hole. A design equation was unposed depending on the embedment depth of the anchor bolt.