• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.60-78
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• 1994

For the optimum design of pile foundations, the determination of allowable load should take both the material strength and the geotechnical characteristics of the site into consideration. Through survey of previous construction records in Korea, it was found that most of the design is overconservative and in some cases the design load was higher than the constructed quality. Proper analysis making use of WEAP and monitoring of pile driving by PDA have been proved to solve most of the prevailing problems. In addition, the time effect in the evaluation of pile bearing capacity has the must significant effect and should not be ignored in the pile design.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.5
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• pp.73-81
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• 2008

This study evaluated the applicability of in-situ concrete pile as a stabilization materials of embankment slopes including agricultural reservoir and rural road etc. The experimental embankment slopes was constructed to investigate the strength properties of in-situ concrete pile with embankment materials and boring methods. The test variable were applied the boring method(driving and augering) and water-cement ratio. In order to analyze the physical and mechanical properties of embankment materials, permeability and water contents test were was performed. Also, the freshly and harden of in-situ concrete properties were measured by the slump and compressive strength tests. The results showed the water content and permeability of embankment materials and boring methods affected on compressive strength of in-situ concrete pile.

• Land and Housing Review
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• v.4 no.3
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• pp.279-286
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• 2013

Driving a prefabricated pile is the efficient construction method with low cost and excellent bearing capacity charateristics. But pile drinving method has often been changed to bored pile method with mechanical boring due to the unexpected problems occurred in the various domestic ground condition with landfill. So, pile driving method has more uncertainty than the Bored Pile method. This paper proposed LRFD design value which is one of limit states design method for the PHC driven pile used as building foundation to guarantee the reliable design with reduced uncertainty. This paper analysed 221 dynamic load test results(E.O.I.D : 93, Resrike : 128) and the different methods of estimating bearing design(Meyerhof method & SPT-CPT conversion method), and proposed LRFD value for each design reliability Index 2.33 and 3.0 for PHC driven pile. LRFD value of PHC driven pile represents 0.43~0.55 for Meyerhof method and 0.40~0.49 for SPT-CPT conversion method according to the deign reliability index.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.58-66
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• 2011

This study presents the behavior characteristics of buried three-layered pipeline subjected to pile driving loads. The analysis considered the driving energy caused by 7 tonf of ram weight and 1.2m of stroke. Also the distance from vibration resource to pipeline varies in 5m to 30m. The vibration velocity and stress are investigated at the center of pipeline in longitudinal direction. In the same cover depth, attenuation ratio of vibration velocity and von Mises stresses for distance increment has shown a decreasing trend. The maximum stress occurs at the top and bottom for the inner pipe, however, an irregular stress distribution is found for the outer pipe.

• Journal of the Korean GEO-environmental Society
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• v.16 no.7
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• pp.23-33
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• 2015

This paper is results of numerical study for application of sheet pile retaining wall reinforced with H-pile as sheet piles are needed in field for a cutoff wall and are limited to use because of driveability in the ground condition of having a larger strength than a weathered rock. Extensive 101 cases of numerical approach were conducted to investigate the behavior of sheet pile retaining wall reinforced with H-pile, changing installing members of two types of sheet pile and three types of H-pile, the embedded depth of sheet pile and H-pile, the horizontal space between H-piles and excavation conditions. As the results of numerical analysis, combined use of the sheet pile SP-IIIA with H-Pile H250 and the sheet pile SP-IV with H-Pile H350 among precast products was found to be efficient since two members tended to reach allowable stresses simultaneously or have similar stress concentration ratios. Increased stiffness in reinforced sheet pile showed reduction of lateral displacement of wall. Embedded depth of sheet pile did not affect stability of wall significantly so that driving the penetrable depth of sheet pile should be enough to maintain stability of wall and satisfy purposes of cutoff and stiffness increase of wall.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.1
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• pp.103-109
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• 2007

A new steel sheet pile of wide hat-type was developed. Advantage of using wide type of sheet pile is reducing steel weight and consequently cutting down construction cost. Field driveability tests were conducted in order to verifying vibro-driveability of wide hat-type sheet pile. As a result of the tests, penetration rates of newly developed sheet piles were less than those of U-type sheet piles. Axial stresses developed in sheet pile during driving were fur less than yield stress of sheet pile. Futhermore, initial penetration rates of sheet piles were much larger than those obtained from WEAP program.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.199-206
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• 2002

The bearing capacity of open-ended piles is affected by the degree of soil plugging, which is quantified by the incremental filling ratio, IFR. However, most design criteria for open-ended piles do not consider the variation of pile bearing capacity with IFR. In this study, new design equations for calculating the pile base and shaft load capacities, based on IFR value of the pile, were proposed using the results of model pile tests. A full-scale pile load test was also conducted on fully instrumented open-ended pile driven into gravelly sand. The IFR for the pile was continuously measured during pile driving. In order to check the accuracy of predictions made with the proposed equations, the equations were applied to two examples, including the pile load test preformed in this study. Based on the comparisons with the pile load tests results, the proposed equations appear to produce satisfactory predictions.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.473-480
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• 2014

Upon setting up a dedicated plastic greenhouse for tomato cultivation developed by the Rural Development Administration on the Gyehwa reclaimed land, this study was aimed at analyzing the problems can be occurred in the installation of plastic greenhouse on reclaimed lands as well as finding out solutions for improvement. A relatively cheaper wooden pile was used in the installation in order to supplement the soft ground conditions. Based on the results of ground investigation of the installation site, both the allowable bearing capacity and pulling resistance of the wooden pile with a diameter of 150 mm and a length of 10 m were computed and came out to be 30.645 kN. It was determined that the values were enough to withstand the maximum compressive force (17.206 kN) and the pullout force (20.435 kN) that are generally applied to the greenhouse footing. There are three problems aroused in the process of greenhouse installation, and the corresponding countermeasures are as follow. First, due to the slightly bent shape of the wooden pile, there were phenomenon such as deviation, torsion, and fracture when driving the pile. This could be prevented by the use of the backhoe (0.2) rotating tongs, which are holding the pile, to drive the pile while pushing to the direction of the driving and fixing it until 5 m below ground and applying a soft vibrating pressure until the first 2 m. Second, there exists a concrete independent footing between the column of the greenhouse and the wooden pile driven to the underground water level. Since it is difficult to accurately drive the pile on this independent footing, the problem of footing baseplate used to fix the column being off the independent footing was occurred. In order to handle with this matter, the diameter of the independent footing was changed from 200 mm to 300 mm. Last, after films were covered in the condition that the reinforcing frame and bracing are not installed, there was a phenomenon of columns being pushed away by the strong wind to the maximum of $11m{\cdot}s^{-1}$. It is encouraged to avoid constructions in winter, and the film covering jobs always to be done after the frame construction is completely over. The height of the independent footing was measured for 9 months after the completion of the greenhouse installation, and it was found to be within the margin of error meaning that there was no subsidence. The extent to the framework distortion and the value of inclinometers as well showed not much alteration. In other words, the wooden pile was designed to have a sufficient bearing capacity.

• Journal of the Korean Geotechnical Society
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• v.15 no.6
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• pp.29-44
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• 1999

This paper shows the results of model tests on the lateral behavior of single rigid pile, which was constructed by driving, in homogeneous and non-homogeneous (two layered) NakDong River sands. The purpose of the present paper is to investigate the effect of ratio of lower layer thickness to embedded pile length, relative density of sand and pile construction conditions (Driven & Embedded piles) on the characteristics of lateral behavior of single pile. These effects can be quantified only by the results of model tests. As a model result, the lateral behavior depends upon the pile construction condition in loose-density soil more than in high-density soil. If the pile construction depends upon driving construction, the decrease of deflection remarkably increases for both loose homogeneous sand and non-homogeneous soil$(E_{h1}/E_{h2}/=0.18)$ with high thickness of upper layer but the decrease of maximum bending moment shows the opposite result to the decrease of deflection. And, with respect to deflection, it was found that the deflection ratio $(y_{Driven}y_{Embedded})$ of embedded to driven piles has the ranges of 0.65 - 0.88 $(D_r=90%)$0.38 - 0.65 $(D_r=61.8%)$ for each relative density of homogeneous soil and the range of 0.6 - 0.88 for non-homogeneous soil. Also, in this study, the experimental equation for the effects of drop height (DH) and H/L on the ratios of $y_D/y_E\; and MBM_D/MBM_ E$ is suggested from model tests.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.21 no.4
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• pp.393-401
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• 2003

Automatic control technologies for the marine pile driving provides accurate and rapid intruding into the planned positions of the pile with planned slope and direction, so that the construction maintenance and management are more efficient and the quality of the construction is more promising. Therefore, in this study, the application scheme of RTK GPS to the automatic control of the pile driving presented. It is expected that the presented scheme using the precise RTK GPS technique assures the efficient and economic 3D positioning accuracy for the precise marine construction management like the precise foundation of marine structures made of piles and the dredging work. It is found that the suggested scheme decrease 60% of the construction error compared with specifications reference because marine position accuracy is measured within 4cm in real time. In addition, the automatic position control system using GPS reduced the construction period and cost compared with existing methods about 30% and 35%, respectively.