• Geotechnical Engineering
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• v.11 no.2
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• pp.19-28
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• 1995

Based on the various test data acquired in the field, the large pressure chamber and the small pressure chamber, uplift behaviors and method of determining the ultimate uplift capacity of pile driven in small pressure chamber were studied. After uplift pile experienced 2 or 3 sudden slip due to increase of uplift load, complete pullout failure was occurred. Thus, it appears that the ultimate uplift capacity could be identified as the load at displacement where first slip occurs. The ultimate uplift capacity might be determined in every test and the disturbance after first uplift test could be recovered by adding one blow of the drop hammer, which had to depend on the model pile capacity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1219-1227
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• 1994

For Determination of the ultimate uplift capacity, the failure mechanism of the foundation by uplift should be correctly known. However, studies on the variation of the failure mechanism with the embedment ratio of anchor plate among those factors governing the uplift resistance are scarce. In this study. in an attempt to observe more clearly the variation of the failure mechanism with embedment ratio and to check applicability of existing formulae for the ultimate uplift capacity. a model test was performed with ground made of carbon rods, simulating a plane strain conditions. As a result, failure characteristics of shallow and deep anchor conditions were clearly classified. It was found that the analysis of a shallow anchor should be made prior to determination of the ultimate uplift capacity of a deep anchor.

• Journal of the Korean Geotechnical Society
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• v.24 no.8
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• pp.89-97
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• 2008

A series of field tests were performed to investigate the behavior of jacket anchor and to evaluate the ultimate bond stress of jacket anchor. From twelve sets of field tests on the jacket anchor and general type ground anchor, it was observed that the pullout resistance of jacket anchor is significantly larger than that of the ground anchor and that the plastic deformation of jacket anchor is significantly smaller than that of general ground anchor at the same loading cycle. Especially in gravel layers, the jacket anchor provides more than 250% increase in ultimate resistance and more than 600% reduction in plastic deformation, compared with the general ground anchor. Finally, the relationship between the injection pressure and overburden pressure is proposed to determine the optimum injection pressure, based on additional field test results.

• Journal of the Korean Geotechnical Society
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• v.25 no.7
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• pp.5-10
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• 2009

The ground anchor is not usually used in soft clay and loose sand, because the pullout resistance of anchors can not be guaranteed. However, there is a method to increase the capacity of anchors using electric discharge geotechnical technologies, which are also known as pulse discharge and electric-spark technologies. The pulse-discharge anchor has a bulbed (or underreamed) bond length that is expanded by high voltage electrokinetic pulse energy. 24 anchors were installed in the weathered soil and sandy clay at the Geotechnical Experimentation Site at Sungkyunkwan University in Suwon, Korea. In this study, in order to define a relation between expansion rate of the anchor diameter and ultimate load, anchor load tests were carried out in accordance with testing procedures by AASHTO (AASHTO 1990) and FHWA (Weatheb 1998). And then several anchors were exhumed to measure the diameter of the pulse discharge anchors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3599-3609
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• 2010

Recently, the construction of coastal structures and high-rise structures against the horizontal and uplift forces increases with the developing the coastal developments. Especially the application of belled tension pile as foundation type to effectively resist uplift force is increasing in coastal structures. However, research on pullout resistance of belled tension pile has been limited and not yet been fully performed. Therefore, the pullout load tests of belled tension piles in four overseas sites were performed, then the bearing capacity, characteristics on load-displacement of piles and load distribution considering skin friction were investigated in this paper. In addition, the limit pullout bearing capacity calculated by the three-dimensional finite element analysis and theoretical methods were compared with values of in-situ test.

• Geotechnical Engineering
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• v.10 no.4
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• pp.39-52
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• 1994

The group effect of inclined ground anchor should be considered in design, but it has been hardly studied due to the difficulties of experimental or theoretical study. In this study, the model tests for the inclined ground anchors are made, and the displacements and strain fields of ground around anchor surface are analysed. As the results of this study, the group effect of the inclined ground anchor in air dried sand ground does not show even though two anchor surfaces are very close(10.7cm, surface to surface). That is to say, ,in the case that the final failure surface by pullout of anchor shows on the anchor surface, the pullout resistances of single anchors are almost same as those of the group anchors in these model tests.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.5
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• pp.87-98
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• 2006

This paper is an experimental result of performing the prototype of anchor tests in field to investigate the ultimate uplifting capacity of permanent anchor embedded in weathered rock. For prototype of actual anchor test in situ, four grouted anchors having various anchor lengths were installed in field and their ultimate uplift capacities were obtained by analyzing test results of load-displacement curves obtained from field uplift tests. On the other hand, creep tests, applying pull-out loading at the stage of the maximum loading during 15 minutes, were performed to investigate ultimate resisting capacity of anchor so that the values of creep rate at the ultimate loading conditions were evaluated. Dial gauges were installed on the surface of ground to measure the vertical displacement distribution from the anchor so that the failure mechanism of permanent anchor embedded in weathered rock and failure boundary of ground during application of loading were evaluated.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.2
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• pp.69-76
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• 2010

This study is an numerical study of predicting the behavior of anchor embedded in weathered rocks, subjected to uplift loads, about ultimate pullout capacity and the failure mechanism. Factors influencing the behavior of anchors were investigated by reviewing the data about in-situ anchor tests performing numerical modelling with changing the bondage length of anchor, diameter of anchor body and diameter of tendon, and by correlations between those factors were evaluated to apply them to predict the behavior of anchors. As results of numerical analysis, a linear relationship between bondage length, diameter of anchor body and diameter of tendon with ultimate pullout capacity was obtained on the one hand, from the result of numerical analysis changing the Young's modulus of weathered rock, this parameter was found to influence to load-displacement and ultimate pullout capacity within the range of 10%, which was not so significant to affect.

• Geotechnical Engineering
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• v.14 no.6
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• pp.5-16
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• 1998

In order to study the behavior of the sheet pile under vertical load in sands, model pile tests using calibration chamber are performed. For this research, five model piles, with the same section area and different degree of inclination of flange, were made. And model pile tests were conducted for each of these piles with different relative density and direction of applied load. For model pile which has the same shape, compression capacity is about 100% higher than pullout capacity and the difference increases with increasing relative density. Pullout ultimate capacity and corresponding displacement increase with increasing relative density and the pullout capacities remained almost the same irrespective of the inclination of flanges for the same density. The ultimate capacity under compression load is highest at 30$^{\circ}$ of inclination of flanges and the trend is more evident with increasing relative density. From the analysis of load distribution, the higher loading capacity at 30$^{\circ}$ of inclination of flanges with same section area may be attributed to the partial soil plug between flanges.

• Journal of Industrial Technology
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• v.21 no.B
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• pp.195-203
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• 2001

The purpose of this study is to estimate ultimate uplift capacity of permanent anchor which was cast into weathered rock. The ultimate uplift capacity was estimated from the load-displacement curve of four different anchors which have different bond length. The creep test was performed for 15minutes under the maximum load of each step in order to understand the load-transfer property of permanent anchor and to decide which anchor to choose. The destruction range of soil due to the changes in load was estimated by installing dial gauge on the ground which was cast into the weathered rock. Ultimately, the study on the behavior of the anchor case into the weathered rock was performed by comparing and analyzing the estimated result of the UUC obtained by the full scale pull out test in the field with the exsting theoretical and practical results of soil and rock anchor.