• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.99-107
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• 2013

In order to investigation Lateral bearing capacity of bored-precast pile, we carried out the analysis of the relationship between Lateral load and horizontal displacement using the result of horizontal pile load test. The six piles injected cement milk of 50%, 70% and 100% of the embedded length of pile were used in the horizontal pile load test. The horizontal displacement, yielding load and horizontal bearing capacity are mainly affected by The injecting ratio of cement milk (injected length of cement milk/embedded length of pile). As the injecting ratio of cement milt is increased, the starting point of horizontal displacement in piles become close to the ground surface and the amount of horizontal displacement is decreased. Also, the horizontal bearing capacity and yielding load are highly increased with increasing the ration of cement milk. The horizontal bearing capacity and yielding load of bored pile with 1 of cement milk ratio are about two or three times those of pile with 0.5 of cement milk ratio.

• Journal of the Korean Geotechnical Society
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• v.29 no.11
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• pp.129-138
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• 2013

In this study, Anchor Pile Precast Retaining Wall (APC) with screw shape flange was investigated and the results were arranged for designing APC specifications. Since precast materials require special care when they are manufactured, carried or treated, more accurate design and analysis of optimized dimension are needed : thus moment distribution of front foot was checked. Through full-scale field test, form and optimal stiffening shape were obtained and through fracture test with real load, applicable load was reasonably calculated. Research result in this thesis could be used as guideline or standard of designing and constructing Anchor Pile Precast Retaining Wall with screw shape flange.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.787-788
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• 2009

• Journal of the Korean Geotechnical Society
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• v.37 no.6
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• pp.5-20
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• 2021

In this study, a modified empirical formula for estimating the bearing capacity of the steel pipe prebored and precast pile was proposed by performing 20 cases of real-scale field pile loading tests. The proposed formula will be based on expanded SPT N-value in order to consider the realistic condition of the surrounding soil. The formula is proposed based on a statistic approach of the data points from the field pile loading test, in order to ensure safe engineering practice while finding a reliable formula. The statistical analysis of the data points from the loading test indicated that the existing formula has been underestimated the bearing capacity of the prebored and precast pile. The proposed formula estimates 15% and 20% higher pile End bearing capacity (q_t=230P_driven(kN/m²)) and the shaft resistance (f_max=3.0N_s^E(kN/m²)) compared to the existing formula. The accuracy and the stability of the proposed formula was verified by comparing the estimated results with additional field test data. The verification process showed that the proposed formula was estimated to be more accurate than the existing formula.

• Journal of the Korean GEO-environmental Society
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• v.11 no.7
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• pp.15-24
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• 2010

Noise and vibration due to pile driving cause residents nearby construction sites to file civil complaints and to the extent of bringing construction to a halt. To deal with this issue, construction engineers have worked strenuously to develop several types of low noise & low vibration pile methods. In this study, a new noise and vibration-free precast screw pile method proposed as a low noise & low vibration pile. It penetrates into the ground by rotating and pressing to avert noise and vibration while maximizing bearing capacity. A prototype of noise and vibration-free precast screw pile method was manufactured, which is not seen anywhere in Korea and elsewhere, and have undergone pilot tests twice to determine construction method. Based on this study, features of the noise & vibration-free screw pile method, production of screw concrete pile prototype, two pilot tests and subsequent construction method were determined.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.20-27
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• 2014

In the construction site, various earth retaining systems are developed and applied to maintain stability of excavated area and structures. Among the methods, the underground continuous wall and the column-type diaphragm wall methods are especially used in construction site nearby buildings or roads. However, these methods have some disadvantages such as the difficulty of quality control and long curing time because these methods need to cast fresh concrete at the construction site. In addition, these methods are usually applied to the site for the temporary purpose. In this paper, we suggest precast hollow prestressed concrete pile for continuous pile wall system. To investigate the structural behavior of suggested pile, which is the main member of the suggested system, tests pertaining to the structural behavior and prestressing force applied in the pile are conducted. From the test results, it was found that the prestressing force measured is sufficient compared with the value obtained by the design equation and the cracking moment measured is 34% higher than the design value. In addition to the above, this precast hollow prestressed concrete pile has an additional safety margin that the maximum moment is 59.2% higher than the cracking moment which is one of the serviceability limits for the design of the system.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.558-561
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• 2001

SIP(Soil cement Injected Precast pile) that inserts a precast pile after injecting a cement paste into a boring has been applied rapidly through the change of construction circumstances. But there isnt any logical equation of a bearing capacity fitted to SIP yet. So Meyerhof equation has mainly been used to predict a bearing capacity in a design stage instead. But it has shortcomings such as lack of confidence because it has derived not from a theory but from an experience obtained from the result of SPT (Standard Penetration Test) and because a penetration depth tends to be deeper by an excessive design that depends on an end bearing capacity of a pile more than a skin frictional resistance. In this study, thereupon, a direct shear test in the laboratory was performed to both SM and SC soils in variable conditions to verify skin friction properties for the purpose of presenting some reasons capable of reducing penetration depths. Through the tests, soil to soil of SM in cohesion, rough panel to soil of SM in friction angle and soil to soil of SM in shear strength tended to be high. And a shear strength increased as its total unit weight increased in all cases.

• Journal of the Korean Geotechnical Society
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• v.34 no.12
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• pp.43-58
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• 2018

In this study, the load-transfer behavior along the shaft of the prebored and precast piles was investigated by pile loading tests. Special attention was given to quantifying the skin frictions developed between the pile-soil interfaces of the 14 instrumented test piles. Based on this detailed field tests, the load - settlement curves and axial load distributions of piles were obtained and the load-transfer curves (t-z curves) for the test piles were proposed. As such, it is found that the test results show two different load transfer behaviors; ductile and brittle behavior curves. The corresponding t-z curves are proposed based on the hyperbolic- and sawtooth-shape, respectively. By validating the accuracy of the proposed curves, it is also found that the prediction results based on the proposed load-transfer curve are in good agreement with the general trends observed by the field loading tests.

• Earthquakes and Structures
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• v.16 no.4
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• pp.455-468
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• 2019

The behavior of pile-deck connections of pile-supported marginal wharfs subjected to earthquake loading is of key importance to ensure a good performance of this type of structures. Two precast-pretensioned pile-deck connections used in the construction of pile-supported marginal wharfs were tested under cyclic loading. The first is a connection with simple reinforcement details and light steel ratio developed for use where moderate pile-deck rotation demands are expected in the wharf. The second is specifically developed to sustain the large rotation, shear force and bending moment demands, as required for the shortest piles in a marginal wharf. Data obtained from the test program is used in the paper to calibrate an equivalent plastic hinge length that can be incorporated into nonlinear analysis models of these structures when prestressed pile-deck connections with duct embedded dowels are used.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.567-574
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• 2002

Rapid urbanization of many cities require large scale constructions such as high rise buildings in difficult ground conditions. SIP(Soil-cement Injected Precast pile) type piles are tile most popular choice of foundation method in soft ground as well as layered ground in many cities in Korea since SIP offer negligible amount of noise and vibration. But SIP method of construction provide wide range of pile capacity depending on the construction method, equipment, ground conditions and quality control method etc. Therefore this paper intend to investigate the reliability of SIP pile in layered ground through a comparison of existing design formulars and SIP pile load test.